This invention is related to an adhesive composition which may be used to bond or seal tissue in vivo. The adhesive composition is readily formed from a two component mixture which includes a first part of a protein, preferably a serum albumin protein, in an aqueous buffer having a pH in the range of about 8.0-11.0 and a second part of a water-compatible or water-soluble bifunctional crosslinking agent. When the two parts of the mixture are combined, the mixture is initially a liquid which cures in vivo on the surface of tissue in less than about one minute to give a strong, flexible, pliant substantive composition which bonds to the tissue and is absorbed in about four to sixty days. The adhesive composition may be used either to bond tissue, to seal tissue or to prevent tissue adhesions caused by surgery.
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0. 113. A method of treating tissue comprising:
providing a composition to tissue, said composition including a serum albumin protein at about 20-60 wt/vol % and a crosslinking agent at about 50-800 mg/ml, said crosslinking agent having a polyoxyethylene chain portion and an activated leaving group which allows the crosslinking agent to react with said protein and having a molecular weight in a range of about 1000-15,000; and curing said composition on the tissue to bond said composition to the tissue and to provide a substantive cured matrix that has a burst strength greater than about 10 mm Hg.
0. 80. A method of treating tissue to bind layers of tissue together comprising:
providing a composition to tissue, said composition including a serum albumin protein at about 20-60 wt/vol % and a crosslinking agent at about 50-800 mg/ml, said crosslinking agent having a polyoxyethylene chain portion and an activated leaving group which allows the crosslinking agent to react with said protein and having a molecular weight in the range of about 1000-15,000; and curing said composition on the tissue to bond said composition to the tissue and to provide a substantive cured matrix that has a burst strength of greater than about 10 mm Hg.
0. 50. A method of treating tissue to prevent formation of an adhesion comprising:
providing a composition to tissue, said composition including a serum albumin protein at about 20-60 wt/vol % and a crosslinking agent of about 50-800 mg/ml, said crosslinking agent having a polyoxyethylene chain portion and an activated leaving group which allows the crosslinking agent to react with said protein and having a molecular weight in the range of about 1,000-15,000; and curing said composition on the tissue to bond said composition to the tissue and to provide a substantive cured matrix that has a burst strength greater than about 10 mm Hg.
0. 18. A method of treating tissue to prevent or control air or fluid leaks comprising:
providing a composition to tissue, said composition including a serum albumin protein at about 20-60 wt/vol % and a crosslinking agent at about 50-800 mg/ml, said crosslinking agent having a polyoxyethylene chain portion and an activated leaving group which allows the crosslinking agent to react with said protein and having a molecular weight in a range of about 1,000-15,000; and curing said composition on the tissue to bond said composition to the tissue and to provide a substantive cured matrix that has a burst strength greater than about 10 mm Hg.
1. An adhesive composition consisting essentially of
i) a first aqueous mixture of about 20-60 wt/vol % serum albumin in about 0.01-0.25 molar buffer at a pH in a range of about 8.0-11.0, ii) a second aqueous mixture of about 50-800 mg/ml of a crosslinking agent having a molecular weight in a range of about 1,000-15,000, wherein the crosslinking agent is of the formula
wherein --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; wherein --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula, --C(O)--, a monoester diradical of the formula, --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula, --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone and p-dioxanone; and wherein --G is a leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl, or and tresyl, ; and wherein a combination of the first and second mixtures is initially liquid and then cures on the surface of tissue to give a flexible, substantive matrix which bonds to the tissue and has a burst strength greater than about 10 mmHg.
17. A method of making a tissue adhesive consisting of the step of forming a mixture of
i) a first aqueous mixture of about 20-60 wt/vol % serum albumin in about 0.01-0.25 molar buffer at a pH in a range of about 8.0-11.0, ii) a second aqueous mixture of about 50-800 mg/ml of a crosslinking agent having a molecular weight in a range of about 1,000-15,000, wherein the crosslinking agent is of the formula
wherein --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; wherein --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula, --C(O)--, a monoester diradical of the formula, --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula, --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone and p-dioxanone; and wherein --G is a leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl or , and tresyl, ; and wherein a combination of the first and second mixtures is initially liquid and then cures on the surface of tissue to give a flexible, substantive matrix which bonds to the tissue and has a burst strength greater than about 10 mmHg.
2. The adhesive mixture composition of
4. The adhesive composition of
5. The adhesive composition of
6. The adhesive composition of
7. The adhesive composition of
9. An in vivo method of adhering tissue comprising the steps of topically applying and bonding an adhesive mixture composition of
10. An in vivo method of sealing air leaks in pulmonary tissues comprising the step of topically applying and curing the adhesive mixture composition of claims claim 1 to an air leak site in the pulmonary tissue.
11. An in vivo method to prevent post-surgical adhesions comprising the step of topically applying and curing the adhesive mixture composition of claims claim 1 to tissue surrounding a surgical site.
12. An in vivo method to seal tissue comprising the step of topically applying and bonding the adhesive mixture composition of claims claim 1 to tissue to prevent or control blood or other fluid leaks.
13. The adhesive composition of
14. The adhesive composition of
15. The adhesive mixture composition of
16. The adhesive composition of claim 15 1 wherein --LM-- is a an oligomeric diradical derived from polyglycolic acid.
0. 19. The method of
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0. 30. The method of
0. 31. The method of
0. 32. The method of
0. 33. The method of
0. 34. The method of
wherein the first mixture includes about 20-60 wt/vol % of the protein in about 0.01-0.25 molar buffer at pH in a range of about 8.0-11.0 and the second mixture includes about 50-800 mg/ml of the crosslinking agent having a molecular weight in a range of about 1,000-15,000.
0. 35. The method of
wherein: --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula --C(O)--, a monoester diradical of the formula --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone; and --G is the leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl, and tresyl.
0. 36. The method of
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0. 60. The method of
0. 61. The method of
0. 62. The method of
0. 63. The method of
0. 64. The method of
0. 65. The method of
0. 66. The method of
wherein the first mixture includes about 20-60 wt/vol % of the protein in about 0.01-0.25 molar buffer at a pH in a range of about 8.0-11.0 and the second mixture includes about 50-800 mg/ml of the crosslinking agent having a molecular weight in a range of about 1,000-15,000.
0. 67. The method of
wherein: --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula --C(O)--, a monoester diradical of the formula --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone; and --G is the leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl, and tresyl.
0. 68. The method of
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0. 92. The method of
0. 93. The method of
0. 94. The method of
0. 95. The method of
0. 96. The method of
wherein the first mixture includes about 20-60 wt/vol % of the protein in about 0.01-0.25 molar buffer at a pH in a range of about 8.0-11.0 and the second mixture includes about 50-800 mg/ml of the crosslinking agent having a molecular weight in a range of about 1,000-15,000.
0. 97. The method of
wherein: --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula --C(O)--, a monoester diradical of the formula --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone; and --G is the leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl, and tresyl.
0. 98. The method of
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0. 128. The method of
0. 129. The method of
wherein the first mixture includes about 20-60 wt/vol % of the protein in about 0.01-0.25 molar buffer at a pH in a range of about 8.0-11.0 and the second mixture includes about 50-800 mg/ml of the crosslinking agent having a molecular weight in a range of about 1,000-15,000.
0. 130. The method of
wherein: --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; --LM-- is a diradical fragment selected from the group consisting of a carbonate diradical of the formula --C(O)--, a monoester diradical of the formula --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical of the formula --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the diradical may be saturated or unsaturated, a dicarbonate diradical of the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, and an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric fragments selected from the group consisting of lactide, glycolide, trimethylene carbonate, caprolactone, and p-dioxanone; and --G is the leaving group selected from the group consisting of succinimidyl, maleimidyl, phthalimidyl, imidazolyl, nitrophenyl, and tresyl.
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0. 154. The method of
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The present invention is related to an adhesive composition which has high mechanical strength, flexibility, fast cure rate and sufficient adhesion needed to bond and/or seal tissue in vivo. The adhesive composition is made of two components, a buffered basic protein solution and a bifunctional crosslinking agent. The buffered protein solution and the bifunctional crosslinking agent are typically prepared using commercially available materials and established synthetic methods. The use of known, commercially available materials in the preparation of the adhesive composition provides a benefit in the practice of this invention because most of these materials generally have a history of clinical safety and/or use.
Suitable proteins for use in the present adhesive composition include nonimmunogenic, water soluble proteins. Serum lipoproteins are particularly well suited for this purpose because these proteins bind to lipids and also exhibit a relatively high elasticity in the natured or semi-natured state. These properties are believed to provide a cured matrix which is strong as well as pliant and elastic. Other soluble proteins, in addition to serum lipoproteins, are also suitable for use in the present invention. Aqueous mixtures of proteins such as derivatives of elastin, fibrinogen and collagen may be used in the present invention.
Preferred buffered protein solutions which may be used in the present adhesive composition include concentrated aqueous serum albumin protein mixtures that are buffered to a pH of between about 8.0-11.0 where the buffer concentration is in a range of about 0.01-0.25 molar. Suitable buffer systems include buffers which are physiologically and/or clinically acceptable such as known carbonate or phosphate buffer systems, provided the buffer does not adversely react with or otherwise alter the crosslinking agent. A preferred buffer system is a carbonate/bicarbonate buffer system at a pH value of about 9.0-10.5 at a concentration in the range of 0.05-0.15 molar.
Serum albumin protein is readily isolated from serum using known isolation processes. In addition, it is possible to produce human serum albumin from genetically transformed cells. See, for example, the reports of Quirk et al., Biotechnology and Applied Biochemistry, 11:273-287 (1989), Kalman et al., Nucleic Acids Research, 18:6075-6081 (1990), Sleep et al., Biotechnology, 8:42-46 (1990), and Sijmons et al., Biotechnology, 8:217-221 (1990). The ability to produce human serum albumin recombinantly provides the benefit that protein produced by this method will be free of pathogens, viruses or other contaminants that might contaminate albumin that is isolated directly from serum.
When used in the present buffered mixtures it has been found that the serum albumin is not denatured. Because the albumin is not denatured before it is used it is believed that the albumin proteins retain their natured, coiled conformation and thus, after being crosslinked during the curing process to provide a gel-like solid, the cured adhesive retains sufficient flexibility to provide a suitable adhesive matrix.
A variety of suitable crosslinking agents may be used in the present invention. Preferred crosslinking agents include a polyethylene glycol or polyoxyethylene chain portion (--PEG--), an activated leaving group portion (--G) and a linking moiety (--LM--) which binds the --PEG-- portion and the leaving group portion --G. Crosslinking agents include compounds of the formula
in which --PEG-- is a diradical fragment represented by the formula
where a is an integer from 20-300; --LM-- is also a diradical fragment such as a carbonate diradical represented by the formula, --C(O)--, a monoester diradical represented by the formula, --(CH2)bC(O)-- where b is an integer from 1-5, a diester diradical represented by the formula, --C(O)--(CH2)c--C(O)-- where c is an integer from 2-10 and where the aliphatic portion of the radical may be saturated or unsaturated, a dicarbonate represented by the formula --C(O)--O--(CH2)d--O--C(O)-- where d is an integer from 2-10, or an oligomeric diradical represented by the formulas --R--C(O)--, --R--C(O)--(CH2)c--C(O)--, or --R--C(O)--O--(CH2)d--O--C(O)-- where c is an integer from 2-10, d is an integer from 2-10, and R is a polymer or copolymer having 1-10 monomeric lactide, glycolide, trimethylene carbonate, caprolactone or p-dioxanone fragments; and --G is a leaving group such as a succinimidyl, maleimidyl, phthalimidyl, or alternatively, nitrophenyl, imidazolyl or tresyl leaving groups.
The --PEG-- portion of the crosslinking agent is preferably derived from commercially available compounds having a weight average molecular weight in the range of about 1,000-15,000, preferably having a weight average molecular weight in the range of about 2,000-4,000. These compounds have been used in different types of biomedical materials because they have been demonstrated to be non-toxic as well as rapidly excreted from the body when the molecular weight is below about 30,000.
The leaving group, --G, portion of the crosslinking agent is an activated leaving group which allows the crosslinking agent to react or chemically bind to free primary or secondary amine groups of a protein. Suitable leaving groups include succinimidyl, other imides such as maleimidyl and phthalimidyl, heterocyclic leaving groups such as imidazolyl, aromatic leaving groups such as a nitrophenyl, or fluorinated alkylsulfone leaving groups such as tresyl (CF3--CH2--SO2--O--). A preferred leaving group is the succinimidyl group because studies of the mutagenicity, oncogenicity and teratogenicity of this group suggest that the small amount of this activating group which is released as the crosslinking reaction and/or the adhesive composition cures does not present a local or systemic toxicology risk.
When used in the present composition the linking moiety, --LM--, may be several different types of divalent compounds. For example, commercially available compounds having the --PEG-- portion and the --G portion linked with a saturated dicarboxylic acid such as succinic acid to give a saturated diester linking moiety. Alternatively, an unsaturated dicarboxylic acid such as fumaric, maleic, phthalic or terephthalic acid may be used to give an unsaturated diester linking moiety. Alternatively, the linking moiety may be a readily hydrolyzable compounds such as oligomer derivatives of polylactic acid, polyglycolic acid, polydioxanone, polytrimethylene carbonate, or polycaprolactone as well as copolymers made using suitable monomers of these listed polymers.
In another embodiment of this invention an activated leaving group may be attached directly to a carbonate ester of polyethylene glycol. In this embodiment the linking moiety, --LM--, would be a carbonate group, --C(O)-- between the --PEG-- and --G portions of the crosslinking agent. In still other embodiments of this invention the linking moiety may be a dicarbonate such as ethylene carbonate which is prepared by linking the --PEG and --G portions with ethylene bischloroformate.
The crosslinking agents may be prepared using known processes, procedures or synthetic methods such as the procedures reported in U.S. Pat. Nos. 4,101,380 or 4,839,345, the procedure reported in International Application Ser. No. PCT/US90/02133 filed Apr. 19, 1990 or the procedure reported by Abuchowski et al., Cancer Biochem. Biophys., 7:175-186 (1984). Briefly, polyethylene glycol and a suitable acid anhydride are dissolved in a suitable polar organic solvent in the presence of base and refluxed for a period of time sufficient to form a polyethylene glycol diester diacid. The diester diacid is then reacted with a leaving group such as an N-hydroxy imide compound in a suitable polar organic solvent in the presence of dicyclohexylcarbodiimide or other condensing agents and stirred at room temperature to form the desired bifunctional crosslinking agent.
Alternatively, polyethylene glycol and a suitable dicarboxylic acid chloride or bischloroformate may be dissolved in a suitable polar organic solvent for a period of time sufficient to form the mixed acid chloride polyethylene glycol ester or mixed chloroformate polyethylene glycol ester. The mixed esters may then be reacted with a compound such as an N-hydroxy imide compound in a suitable polar organic solvent and stirred at an elevated temperature for a period of time sufficient to form the desired bifunctional crosslinking agent.
It has also been found that the cure time of the present adhesive compositions may be tailored by use of buffers having different pH values. For example, by varying the pH of the buffer it is possible to change the cure rate time from about 10 seconds to less than about 10 minutes. Briefly, mixing concentrated aqueous serum albumin and crosslinking agent mixtures with higher concentrations of buffer provides the fastest cure times. It has also been found that higher concentrations of protein and crosslinking agent provide a relatively stronger, cured matrix. However, if the mixtures are too concentrated and viscosity becomes too great, these adhesive compositions are not as readily applied or may provide adhesives with undesired properties. For example, mixtures which are too viscous may not be readily applied using available applicators such as syringes or spray apparatus. In addition, if the concentration of crosslinking agent is too high, the resulting cured adhesive matrix may swell to such an extent that the strength of the matrix in the presence of water or other fluids is lowered. Further, ability to adequately mix the two components using injecting and/or spraying apparatus may be reduced.
The two component adhesive composition of the present invention may be applied to tissue in a number of different ways. For example, the adhesive may be quickly mixed together and then applied using common applicators. Alternatively the two components may be mixed together and then applied as spray. In another application method, the two parts of the adhesive are added to a dual syringe. The two barrels of the syringe are attached to a "Y" connect which is fitted to a spiral mixer nozzle. As the two components are pressed out of the syringe, they are mixed in the nozzle and may be directly applied to the tissue as needed in a relatively uniform, controlled manner. Alternatively, a spray nozzle tip, such as a TISSEEL spray tip sold by Immuno AG, Vienna, Austria for use with a two-component fibrin sealant kit, may be used in place of the spiral mixer nozzle. In this application, a fine spray of the adhesive composition is deposited on tissue as the plungers of the syringe are depressed.
The adhesive composition of the present invention may be used in a variety of current medical procedures and practices. In one application, the present adhesive composition may be used to eliminate or substantially reduce the number of sutures normally required using current practices as well as eliminate the need for subsequent removal of certain sutures. In another application, this adhesive composition may be used to attach skin grafts and to position tissue flaps or free flaps during reconstructive surgery. In still another application, this adhesive composition may be used to close gingival flaps in periodontal surgery. In all of these applications, the present adhesive composition is a thin layer of cured material which is effectively sandwiched between two adjacent layers of living tissues. Due to bioabsorbability and lack of toxicity of the adhesive composition, the healing and subsequent reattachment of the two layers of tissue to each other is not hampered.
In addition to the use of the present adhesive composition as an adhesive per se, the present composition may also be used as a sealant. When used in this application, this composition may be used to prevent air leaks now associated with pulmonary surgery or to inhibit or prevent bleeding in other surgical procedures. When used in this manner, the underlying tissue may be coated with a relatively thick layer of adhesive since the tissue itself needs to only heal on one side. The other side of the of the adhesive, when cured, simply presents a lubricous gel which will be absorbed in vivo in a relatively short period of time from about four to sixty days. In view of this property of the present adhesive composition, it may also be used to prevent unwanted tissues adhesions which are associated with current surgical procedures.
The following examples are intended to describe and illustrate the practice of the claimed invention. The examples, however, should not be construed to limit the scope of the present invention which is defined by the appended claims.
The following procedures were used to prepare several different types of bifunctional crosslinking agents. The following procedures are modifications of procedures reported in U.S. Pat. No. 4,101,380 and Abuchowski et at., cited above.
Synthesis of Polyethylene Glycol Disuccinimidyl Succinate PEG-SS2
Polyethylene glycol, PEG, (50 g, Aldrich Chemical Company, Milwaukee, Wis., sold as 3,400 average molecular weight, GPC analysis Mn was 2,980, Mw, was 3,480) was dissolved in 1,2-dichloroethane (250 ml) containing succinic arthydride (14.7 g) and anhydrous pyridine (12 ml). The mixture was refluxed under nitrogen for three days. After filtration and evaporation of the solvent, the residue was dissolved in 100 ml water and treated with the cation exchange resin Dowex™ 50 (H+) (50 g) for 30 minutes. The mixture was then filtered and the Dowex™ 50 was washed with water (50 ml 1×). The combined filtrate was washed with anhydrous diethyl ether (50 ml 2×). The PEG-disuccinate was then extracted from the water phase with two 100 ml chloroform washes. Evaporation of chloroform yielded about 49 g of PEG-disuccinate.
The PEG-disuccinate was dissolved in 200 ml N,N-dimethylformamide (DMF) at 37°C C. and 4.23 g of N-hydroxysuccinimide (NHS) were added to the solution. The mixture was cooled to 0°C C. 7.58 g of dicyclohexylcarbodiimide (DCC) were dissolved in 50 ml DMF and added dropwise to the above solution with continuous stirring. The mixture was left at room temperature for 24 hours and filtered. 100 ml of toluene were added to the filtrate and the solution was placed in an ice bath. The desired polyethylene glycol disuccinimidyl succinate product, PEG-SS2, was precipitated by slowly adding petroleum ether. The precipitate was collected on a 10-20 micron sintered glass filter. Dissolution in toluene and precipitation with petroleum ether was repeated three times. The PEG-SS2 was further purified by dissolving in 100 ml of 0.1M pH 2.2 citrate/phosphate buffer and filtering through a 4-8 micron sintered glass filter. The PEG-SS2 was extracted with chloroform (100 ml 2×) and the solvent was evaporated under reduced pressure in a rotary evaporator. The PEG-SS2 was then dissolved in toluene and precipitated with petroleum ether, dried under vacuum overnight at room temperature, and stored in a refrigerator.
Synthesis of N-hydroxysuccinimide Ester of Dicarboxymethyl Polyethylene Glycol
Dicarboxymethyl poly(ethylene glycol) (mol. wt. 3400) purchased from Shearwater Polymers, Inc., Huntsville, Ala. (5 g) and N-hydroxysuccinimide purchased from Sigma Chemical Co., St. Louis, Mo. (1 g) were dissolved in 30 ml of anhydrous DMF with mechanical stirring under nitrogen. The solution was cooled to 0°C C. and a solution of dicyclohexylcarbodiimide (1.79 g) in 5 ml DMF was added dropwise. The stirring was continued in the cold for 3 hours then at room temperature overnight (16 hrs). Dicyclohexylurea which precipitated was removed by filtration. Toluene (100 ml) was added to the filtrate and cooled to 0°C C. The product was then precipitated by addition of petroleum ether. The precipitate was collected on a sintered glass filter. Dissolution in toluene and reprecipitation with petroleum ether was repeated three times. The product was dried under vacuum in a desiccator.
Synthesis of Polyethylene Glycol-di-oligoglycolide Disuccinimidyl Succinate
A 500 ml three neck round bottom flask was flame dried under nitrogen. 50 g of PEG (mol. wt. 3400), 300 ml of xylene, and 1 drop of 0.33M stannous ottoate solution in xylene were charged into the flask with a continuous nitrogen purge. The flask was heated to boil the solution and 50 ml of xylene were removed by distillation. The solution was then cooled to room temperature. 17 g of glycolide (Boehfinger Ingleheim KG, Ingleheim, Germany) was added to the flask and the reaction mixture was refluxed under nitrogen for 16 hours. The copolymer reaction mixture was filtered hot to remove polyglycolide homopolymer. The copolymer then precipitated from the filtrate upon cooling and collected by filtration. The copolymer was placed in a flask with 500 ml of dichloromethane and 7 g of succinyl chloride. The solution was refluxed under nitrogen overnight (16 hours). 8.5 g of N-hydroxysuccinimide was added to the flask and refluxing was continued for another overnight period. A white solid was obtained by precipitation upon cooling the solution. The product was then purified by redissolving in toluene and reprecipitating with petroleum ether several times. The final precipitate was dried under vacuum and stored in a desiccator. The structure of the product was confirmed by NMR analysis.
Synthesis of Polyethylene Glycol-dimaleimidyl Succinate
About 12 g of PEG-disuccinate and 1 g N-hydroxymaleimide (Aldrich Chemical Co.) were placed in a 250 ml three neck round bottom flask with 50 ml of anhydrous DMF under nitrogen. The mixture was dissolved at 60°C C. with mechanical stirring and cooled to 0°C C. A solution of 1.82 g dicyclohexylcarbodiimide in DMF (5 ml) was added dropwise to the flask. The reaction was allowed to mix overnight under nitrogen at room temperature. Dicyclohexylurea was removed by filtration and the product was obtained by adding toluene and precipitating with petroleum ether. Dissolution in toluene and reprecipitation with petroleum ether were repeated three times. The purified product was dried under vacuum and stored in a desiccator.
Synthesis of Polyethylene Glycol-diphthalimidyl Succinate
About 15 g of PEG-disuccinate and 1.65 g N-hydroxyphthalimide (Aldrich Chemical Co.) were placed in a 250 ml three neck round bottom flask with 30 ml of anhydrous DMF under nitrogen. The mixture was dissolved at 60°C C. with mechanical stirring and cooled to 0°C C. A solution of 1.82 g dicyclohexylcarbodiimide in DMF (5 ml) was added dropwise to the flask. The reaction was allowed to mix overnight under nitrogen at room temperature. Dicyclohexylurea was removed by filtration and the product was obtained by adding toluene and precipitating with petroleum ether. Dissolution in toluene and reprecipitation with petroleum ether were repeated three times. The purified product was dried under vacuum and stored in a desiccator.
Preparation of Two Component Adhesive
The following procedure was used to prepare a two-component adhesive using a variety of protein sources, and bifunctional crosslinking agents. Aqueous solutions of a protein and a crosslinking agent as listed in Table 1 were pipetted (0.2 ml of each solution) into a porcelain test well and mixed continuously with a stainless steel rod. The cure time and physical consistency of each of the two component adhesives are also listed in Table 1.
The data indicated that fish and bovine gelatin, egg and serum albumin as well as casein protein crosslinked with PEG-SS2 provided an adhesive which was very elastic, had good adhesive strength and a relatively rapid cure rate.
| TABLE 1 | ||
| Bifunctional | Cure | |
| Protein | Crosslinking agent | Time Consistency |
| Fish Gelatin | 130 mg/ml | 40 sec Strong gel, very |
| Lot 23H0307 | PEG-SS2 3400 mw | elastic, slightly |
| Sigma | sticky | |
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Fish Gelatin | 260 mg/ml | 40 sec Strong gel, very |
| Lot 23H0307 | PEG-SS2 3400 mw | elastic, slightly |
| Sigma | sticky | |
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Fish Gelatin | 130 mg/ml | 120 sec Soft gel, very |
| Lot 23H0307 | PEG-SS2 10,000 mw | sticky |
| Sigma | ||
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Fish Gelatin | 260 mg/ml | 110 sec Soft gel to |
| Lot 23H0307 | PEG-SS2 10,000 mw | elastic, |
| Sigma | moderately | |
| 40% 0.1 M pH 10 | sticky | |
| Carb/Bicarb | ||
| Gelatin Bovine | 130 mg/ml | 40 sec Soft gel, not |
| Skin Lot 53H0271 | PEG-SS2 3400 mw | elastic |
| Sigma | ||
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Gelatin Bovine | 260 mg/ml | 40 sec Soft gel, not |
| Skin Lot 53H0271 | PEG-SS2 3400 mw | elastic |
| Sigma | ||
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Gelatin Bovine | 130 mg/ml | 40 sec Soft gel, not |
| Skin Lot 53H0271 | PEG-SS2 10,000 mw | elastic |
| Sigma | ||
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Gelatin Bovine | 260 mg/ml | 120 sec Soft gel, not |
| Skin Lot 53H0271 | PEG-SS2 10,000 mw | elastic |
| Sigma | ||
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Casein | 130 mg/ml | 40 sec Strong gel, |
| pH 9.4 12.6% | PEG-SS2 3400 mw | elastic, not sticky |
| Carb/Bicarb | ||
| Poly-L-Lysine | 130 mg/ml | 20 sec Waxy, no |
| 50 mg/ml H2O | PEG-SS2 3400 mw | adhesive strength |
| 300,000 mw | ||
| Carb/Bicarb | ||
| Poly-L-Lysine | 260 mg/ml | 15 sec Waxy, no |
| 50 mg/ml H2O | PEG-SS2 3400 mw | adhesive strength |
| 300,000 mw | ||
| Carb/Bicarb | ||
| Poly-L-Lysine | 130 mg/ml | 10 sec Waxy, no |
| 50 mg/ml H2O | PEG-SS2 10,000 mw | adhesive strength |
| 300,000 mw | ||
| Carb/Bicarb | ||
| Poly-L-Lysine | 260 mg/ml | 10 sec Waxy, no |
| 50 mg/ml H2O | PEG-SS2 10,000 mw | adhesive strength |
| 300,000 mw | ||
| Carb/Bicarb | ||
| Chicken Egg | 130 mg/ml | 210 sec soft, tacky |
| Albumin | PEG-SS2 3400 mw | |
| 40% 0.08 M pH 10 | ||
| Carb/Bicarb | ||
| Rabbit Serum | 130 mg/ml | 20 sec Very elastic, |
| Albumin | PEG-SS2 3400 mw | good adhesive |
| (RSA) Sigma | strength, not | |
| Lot 19F9301 | sticky | |
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| Human Serum | 130 mg/ml | 20 sec Very elastic, |
| Albumin | PEG-SS2 3400 mw | good adhesive |
| (HSA) Sigma | strength, not | |
| Lot 63H9041 | sticky | |
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| HSA | 130 mg/ml | 20 sec Very elastic, |
| Sigma | PEG-SS2 3400 mw | good adhesive |
| Lot 63H9041 | strength, not | |
| 40% 0.1 M pH 10 | ||
| Carb/Bicarb | ||
| HSA | 260 mg/ml | 10 sec Very elastic, |
| Sigma | PEG-SS2 3400 mw | good adhesive |
| Lot 63H9041 | strenght, not | |
| 40% 0.1 M pH 10 | sticky | |
| Carb/Bicarb | ||
| HSA | 130 mg/ml | 30 sec Very elastic, |
| Sigma | PEG-SS2 10,000 mw | slight adhesive |
| Lot 63H9041 | strength, very | |
| 40% 0.1 M pH 10 | sticky | |
| Carb/Bicarb | ||
| HSA | 260 mg/ml | 25 sec Very elastic, |
| Sigma | PEG-SS2 10,000 mw | slight adhesive |
| Lot 63H9041 | strength, very | |
| 40% 0.1 M pH 10 | sticky | |
| Carb/Bicarb | ||
| HSA | 130 mg/ml | 20 sec Turned brown |
| Baxter Healthcare | PEG-dimaleimidyl | upon curing, |
| Corp. | succinate | hard gel, not |
| Lot 2837A238AA | Example 4 | sticky |
| Carb/Bicarb | ||
| HSA | 130 mg/ml | 10 sec Turned red |
| Baxter | PEG-diphthalimidyl | upon curing, hard gel, |
| Lot 2837A238AA | succinate | not sticky |
| Carb/Bicarb | Example 5 | |
| HSA | 130 mg/ml | 8 sec Hard gel, not |
| Baxter | PEG-dicaboxymethyl | sticky, no color |
| Lot 2837A238AA | disuccinimidyl | change |
| Carb/Bicarb | Example 2 | |
| HSA | 130 mg/ml | 40 sec Hard gel, not |
| Baxter | PEG-dioliglycolide | sticky, no color |
| Lot 2837A238AA | disuccinimidyl succinate | change |
| Carb/Bicarb | Example 3 | |
| HSA | 130 mg/ml | 30 sec Hard gel, not |
| Baxter | PEG-disuccinimidyl | sticky, no color |
| Lot 2837A238AA | propionate | change |
| Carb/Bicarb | PED(SPA)2 | |
| HSA | 260 mg/ml | 40 sec Hard gel, not |
| Baxter | PEG-disuccinimidyl | sticky, no color |
| Lot 2837A238AA | propionate | change |
| Carb/Bicarb | PEG(SPA)2 | |
| HSA | 130 mg/ml | 48 hrs Hard gel, not |
| Baxter | PEG-dioxycarbonyl | (cure) sticky, no color |
| Lot 2837A238AA | imidazole | change |
| Carb/Bicarb | PEG(CDl)2 | |
| HSA | 130 mg/ml | 140 sec Hard gel, not |
| Baxter | PEG-dinitrophenyl | sticky, changed |
| Lot 2837A238AA | carbonate | to bright yellow |
| Carb/Bicarb | PEG(NPC)2 | color |
| HSA | 260 mg/ml | 140 sec Hard gel, not |
| Baxter | PEG-dinitrophenyl | sticky, changed |
| Lot 2837A238AA | carbonate | to bright yellow |
| Carb/Bicarb | PEG(NPC)2 | color |
| HSA | 130 mg/ml | 8 hrs Hard gel, not |
| Baxter | PEG-ditresylate | (viscous) sticky, no |
| Lot 2837A238AA | PEG(tres)2 | color 24 hrs change |
| Carb/Bicarb | (cure) | |
| HSA | 130 mg/ml | 72 hrs Hard gel, not |
| Baxter | PEG-diglycidyl ether | (cure) sticky, no color |
| Lot 2837A238AA | PEG(epox)2 | change |
| Carb/Bicarb | ||
| HSA | 130 mg/ml | no cure Liquid |
| Baxter | PEG-dialdehyde | |
| Lot 2837A338AA | PEG(ald)2 | |
| Carb/Bicarb | ||
Effect of Buffer and pH
Two component adhesives were prepared according to the process described in Example 6 except that the pH of the buffer in the protein solution was changed as listed in Table 2. The data indicate that a preferred pH range is about 8.44-10∅
| TABLE 2 | |||
| Crosslinking | |||
| agent | Cure | ||
| Protein | PEG-SS2 | Time | Constistency |
| HSA | 130 mg/ml | 10 min | Initially softer |
| Baxter | 3400 mw | adhesive, hardens | |
| Lot 2837A238AA | with aging | ||
| 40% 0.1 M pH 7.4 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 20 sec | Very elastic, good |
| Sigma | 3400 mw | adhesive strength | |
| Lot 63H9041 | not sticky | ||
| 40% 0.1 M pH 8.44 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 10 sec | Hard gel, not sticky |
| Sigma | 3400 mw | ||
| Lot 63H9041 | |||
| 40% 0.15 M pH 9.07 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 5 sec | Hard gel, not sticky |
| Sigma | 3400 mw | ||
| Lot 63H9041 | |||
| 40% 0.2 M pH 9.52 | |||
| Carb/Bicarb | |||
| HSA | 260 mg/ml | 5 sec | Hard gel, not sticky |
| Sigma | 3400 mw | ||
| Lot 63H9041 | |||
| 40% 0.2 M pH 9.52 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 7 sec | Elastic to hard gel, |
| Sigma | 10,000 mw | slightly sticky | |
| Lot 63H9041 | |||
| 40% 0.2 M pH 9.52 | |||
| Carb/Bicarb | |||
| HSA | 260 mg/ml | 7 sec | Elastic to hard gel, |
| Sigma | 10,000 mw | slightly sticky | |
| Lot 63H9041 | |||
| 40% 0.2 M pH 9.52 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 25 sec | Very elastic, not |
| Baxter | 3400 mw | sticky | |
| Lot 2837A238AA | |||
| 40% 0.1 M pH 10 | |||
| Carb/Bicarb | |||
| HSA | 130 mg/ml | 25 sec | Very elastic, not |
| Sigma | 3400 mw | sticky | |
| Lot 63H9041 | |||
| 40% 0.1 M pH 10 | |||
| Carb/Bicarb | |||
Effect of Crosslinking Agent on Adhesive Strength
A 30% HSA (Human Serum Albumin) solution from Sigma Chemical Co. and a 25% HSA solution from Baxter Healthcare, Inc. were dialyzed against 0.1M carbonate/bicarbonate pH 10 buffer at 4°C C. overnight and concentrated to about 40% by ultra-filtration through a 50,000 molecular weight cut-off cellulose ester disc membrane (Spectrum Medical Industries, Inc.) in a pressure filtration cell under nitrogen at 60 psig. The final concentration was calculated based on the volume of collected filtrate. The maximum concentration obtained under these conditions during overnight ultra-filtration was typically 42-45%. The RSA (Rabbit Serum Albumin) from Sigma and RSA crystallized protein from ICN Biomedical, Inc. were dissolved in 0.1M pH 10 carbonate/bicarbonate buffer and concentrated to 40% by the same method used for HSA.
Various concentrations of PEG-SS2 (3,400 mw and 10,000 mw) were prepared in deionized water. The albumins and crosslinking agent solutions were delivered in equal volume using a 1 ml dual syringe. The syringe tips were fitted with a Y connector which connected to a specially machined TEFLQN adaptor inserted into a 1.8 in.×0.187 in. (4.57 cm×0.475 cm) dia. spiral mixer nozzle (TAH Industries, Inc., Robbinsville, N.J., part no. 150-312). The adhesive mixture was injected through the mixer directly onto the test substrate for adhesion testing.
Freshly excised guinea pig skin was cut into strips and a polystyrene window with an opening of 0.5×1.0 inches (1.27 cm×2.54 cm) was placed on one end of the strip to contain the glue in a specific region. Upon filling the window with glue it was covered with another strip of guinea pig skin. A 500 g steel weight was placed on top of this assembly for about one minute. The sample was peeled apart in the jaws of a computer controlled mechanical testing machine (880 Material Test System, MTS System, Inc., Minneapolis, Minn.) set at a strain rate of 0.8 in./min. (2 cm/min.) with a gage length of 1 in. (2.54 cm) and a 5 lbs. (2.27 kg) load cell. Peel force was recorded after the initiation of adhesive failure as the constant force require to continue peeling as shown in FIG. 1. Four replicates were performed for each test condition. The results of this test are listed in FIG. 2.
Measurement of Adhesive Sealant Burst Strength
A pressurization assembly illustrated in
Two types of membranes were used, either a collagen membrane or a freshly excised porcine pericardium sample. The porcine pericardium sample was either used immediately upon harvest or after storage in a moisture-proof container at 4°C C. for no longer than 24 hours. Under these conditions there was no discernible difference in sealant performance based on storage time of that tissue.
The pressurization sequence was initiated by injecting air into the pressure inlet at a fixed rate of one cubic centimeter per second using a syringe pump (Sage Instruments Model 351, Orion Research, Inc.). The pressure transducer was connected to a digital strain gauge meter (Omega Model DP205-S, Omega. Engineering, Inc.) programmed to read pressure (ram mercury) and to display the peak pressure value at the time of adhesive sealant rupture. Replicate tests gave reproducible peak pressure values and the standard deviation was reported in each case.
Pressure tests were performed with an adhesive composition of 40% HSA (or RSA) in 0.08M carbonate/bicarbonate buffer at different pH values with 3,400 m.wt. PEG-SS2 (130 mg/ml) on collagen and pericardium membranes. The results listed in Table 3 demonstrate excellent sealant performance with typical peak pressure values of about 130 mm Hg.
In addition, the peak pressure for the above sealants after soaking in saline solution was measured. The test was performed as described above except that the surface of the sealant coated membrane was flooded with saline for up to a time period of 90 minutes before pressurization. Although the sealant hydrogel swelled to about double in thickness, substantial retention of sealant performance was retained.
Table 4 shows the data obtained by testing a variety of proteins including fish skin gelatin, chicken egg albumin, and fibrinogen. Fibrinogen mixed with thrombin ("fibrin glue", BERIPLAST-P sealant, Behringwerke, Marburg, Germany) was also used as a control sealant material. None of these materials performed as well as the serum albumin examples. The main disadvantage was the cure and aging time required to achieve significant strength. In particular, chicken egg albumin required twenty-five minutes of post cure aging to achieve the same burst strength obtained from serum albumin aged for less than five minutes.
The same process was repeated for additional 25% HSA solutions by dialyzing against 0.08M carbonate/bicarbonate buffers at pH 9 and pH 8. A pH 7 solution of HSA was obtained by concentration of the original 25% HSA solution to 40% by ultrafiltration. The crosslinking agent solution PEG-SS2 (3400 mw) was 130 mg dissolved in one ml deionized water. The albumin and crosslinking agent solutions were delivered in equal volume using a one ml dual syringe as in Example 8. The pressure tests were performed as above using collagen membrane except that the sealant hydrogel was aged before testing. The results are also listed in Table 4. These data demonstrate that optimal pressure test values are achieved faster with increasing pH of the albumin solution. Moreover, the resultant cured sealant obtained after complete curing has taken place is unexpectedly higher with higher pH of the albumin solution.
| TABLE 3 | |||
| Burst | |||
| Adhesive | Pressure | ||
| Tissue | Tissue Opening | Composition | (mm Hg) |
| Collagen | 4.56 mm dia. hole | HSA:PEG-SS2 | 150 |
| Collagen | 5 mm slit | HSA:PEG-SS2 | 112 |
| Collagen | 4.56 mm dia. hole | RSA:PEG-SS2 | 130 |
| Collagen | 5 mm slit | RSA-PEG-SS2 | 125 |
| Porcine | 4.56 mm dia. hole | HSA:PEG-SS2 | 155 |
| Pericardium | |||
| Porcine | 5 mm slit | HSA:PEG-SS2 | 130 |
| Pericardium | |||
| Porcine | 4.56 mm dia. hole | RSA:PEG-SS2 | 125 |
| Pericardium | |||
| Porcine | 5 mm slit | RSA:PEG-SS2 | 130 |
| Pericardium | |||
| TABLE 4 | |||||
| Pressure Test of Different Proteins Using Collagen and Pericardium | |||||
| HSA: 40% 0.08 M Carb/Bicarb Buffer in Saline Lot #2837a328AA | |||||
| RSA: 40% 0.08 M Carb/Bicarb Buffer in Saline Lot #82-451-0050 INC | |||||
| PEG-SS2: 3400 mw lot #103128-110 (130 mg/ml) | |||||
| Defect: 4.56 mm hole | |||||
| Air Flow Rate: 1 cc/s | |||||
| Pressure | |||||
| (mm Hg) | |||||
| Protein | Crosslinker | Membrane | Ave | St dev | Comments |
| HSA pH 10 | PEG-SS2 | Collagen | 149 | 9 | No bubbles |
| Pericardium | 154 | 4 | 5 min after curing | ||
| Pericardium | 196 | 5 | 10 min after curing | ||
| HSA pH 10 | PEG-SS2 | Collagen | 144 | 5 min after curing | |
| 155 | 10 min after curing | ||||
| 162 | 20 min after curing | ||||
| HSA pH 9 | PEG-SS2 | Collagen | 108 | 5 min after curing | |
| 114 | 10 min after curing | ||||
| 116 | 20 min after curing | ||||
| HSA pH 8 | PEG-SS2 | Collagen | 36 | 5 min after curing | |
| 78 | 10 min after curing | ||||
| 90 | 20 min after curing | ||||
| HSA pH 7 | PEG-SS2 | Collagen | 30 | 10 min after curing | |
| 52 | 20 min after curing | ||||
| RSA pH 10 | PEG-SS2 | Collagen | 134 | 5 | No bubbles |
| Pericardium | 126 | 10 | 5 min after curing | ||
| Pericardium | 194 | 9 | 10 min after curing | ||
| Fish Gelatin pH 10 | PEG-SS2 | Collagen | 34 | 2 | 10 min after curing |
| 40% | |||||
| (Sigma) | |||||
| Chicken Egg | PEG-SS2 | Collagen | 14 | 3 | 10 min after curing |
| Albumin pH 10 | 151 | 5 | 45 min after curing | ||
| 40% | |||||
| (Sigma) | |||||
| Fibrin Glue | Pericardium | 8 | 2 | 5 min after curing | |
| (BERIPLAST-P) | with saline, glue | ||||
| Used according to | slid off easily | ||||
| mfg. instructions | 39 | 2 | 5 min after curing | ||
| without saline, | |||||
| leaked underneath | |||||
| Bovine Fibrinogen | PEG-SS2 | Collagen | 8 | 2 | 5 min after curing |
| pH 10 | 8 | 2 | 60 min after | ||
| 15% | curing, glue slid | ||||
| (Sigma) | off easily | ||||
Use of a Two Component Adhesive Sealant in General and Thoracic Surgery
An anesthetized pig was used as an experimental model for thoracic surgical complications such as staple line leaks during lung and bronchus resections, bronchopleural fistulas, and other conditions resulting in pneumothorax.
The two component adhesive included Part A, a 40% HSA prepared by dialysis of commercially available HSA (25% Solution, BUMINATE 25%, Baxter Healthcare Corp., Hyland Division, Glendale, Calif.) against 0.08M pH 10 carbonate/bicarbonate buffer followed by concentration to 40% by ultrafiltration at 50 psi using a 50,000 molecular weight cut-off cellulose ester disc membrane and Part B, a 130 mg/ml solution of 3,400 m.wt. PEG-SS2 dissolved in sterile distilled water no more than 30 minutes prior to use. The PEG-SS2 was synthesized and purified as described in Example 1.
A stab wound was made on the lung of an anesthetized pig with a scalpel which resulted in significant air leakage during inspiration as evidenced by bubbling of air through irrigation fluid administered to the site. The wound was blotted with gauze to remove blood and fluid. The respirator was turned off and the adhesive was applied as a sealant using a dual syringe (Behring PANTAJECT syringe, Behringwerke, Marburg, Germany) equipped with a spiral mixing tip. After a 20 second cure time ventilation was restored and the lung was again covered with irrigation fluid. No air leaks were observed.
A functional end-to-end anastomosis in pig intestine was conducted using a standard stapling procedure. The adhesive material described above was applied to the staple lines. This resulted in a clear, adherent hydrogel coating which appeared to seal the anastomotic line.
Under these conditions it was observed that anastomotic lines coated with the sealant were air tight whereas anastomotic lines not sealed were not air tight.
Use of Two Component Adhesive to Prevent Post-Surgical Adhesions
The tissue sealant hydrogel tested was a two part liquid system. Part A was a sterile 40% (w/v) solution of human serum albumin in isotonic pH 10 carbonate buffer (0.1M). Part B was a 400 mg/ml solution of 10,000 molecular weight PEG-SS2 (polyethylene glycol disuccinimidyl succinate) in sterile distilled water prepared just prior to use. Solutions A and B were mixed in equal volumes with a dual syringe system connected to a static mixing head (Tah Industries, Inc.).
Post-surgical adhesion prevention evaluation of this sealant formulation was initiated in a series of ten female rabbits. A 2×2 cm area of the abdominal wall was excised down to the fascia on each side of the abdominal cavity exposed by a midline laparotomy incision. The uterine horns were injured by scraping 20 times with a no. 10 scalpel blade. Each animal served as its own control by randomly applying test material to only one of the abdominal wall injuries. The uterine horns were then attached with two stitches to the abdominal wall within a few millimeters of the edge of the wound closest to the laparotomy incision.
Two weeks after surgery the rabbits were examined in order to evaluate and score the extent, type, and tenacity of adhesions present on the abdominal wall injury sites. These results are shown in Table 5. The rating system used to obtain these scores is shown in Table 6. Although technical difficulties were encountered as noted in Table 5, the test material clearly provided an unexpected benefit in both the prevention of adhesions and a reduction in their severity without the presence of a known active ingredient.
| TABLE 5 | ||||||
| Scoring of Adhesions Formed in Material Evaluation | ||||||
| Characteristic | ||||||
| Extent | ||||||
| Treat- | Type | Tenacity | ||||
| Animal | Control | ment | Control | Treatment | Control | Treatment |
| BAM 8 | 2 | 0+ | 3 | 0+ | 3 | 0+ |
| BAM 9 | 3 | 1 | 3 | 1 | 3 | 1 |
| BAM 10 | 0+ | 1 | 0+ | 3 | 0+ | 2 |
| BAM 11 | 0* | 0 | 0* | 0 | 0* | 0 |
| BAM 12 | 4 | 4 | 3 | 3 | 3 | 3 |
| BAM 13 | 2 | 1 | 3 | 2 | 3 | 2 |
| BAM 14 | 1* | 0 | 3* | 0 | 3* | 0 |
| BAM 15 | 1 | 0** | 1 | 0** | 2 | 0** |
| BAM 16 | 1 | 0* | 1 | 0* | 2 | 0* |
| BAM 17 | 1 | 0* | 1 | 0* | 2 | 0* |
| Aver- | 1.5 | 0.7 | 1.5 | 0.9 | 2.1 | 0.8 |
| age | ||||||
| TABLE 6 | ||
| Characteristics | Adhesion Score | |
| Extent (% sidewall Evolvement) | ||
| None | 0 | |
| ≦25 | 1 | |
| ≦50 | 2 | |
| ≦75 | 3 | |
| >75 | 4 | |
| Type | ||
| None | 0 | |
| Filmy, no vessels (transparent) | 1 | |
| Opaque, no vessels (translucent) | 2 | |
| Opaque, small vessels present grossly | 3 | |
| Opaque, larger vessels present grossly | 4 | |
| Tenacity | ||
| None | 0 | |
| Adhesions essentially fell apart | 1 | |
| Adhesions lysed with traction | 2 | |
| Adhesions required sharp dissection for lysis | 3 | |
Scholz, Matthew T., Truong, Myhanh T., Barrows, Thomas H., Lewis, Terry W.
| Patent | Priority | Assignee | Title |
| 10300223, | Jun 25 2014 | Neomend, Inc. | Pleural air leak test system |
| 11571493, | Mar 19 2012 | Neomend, Inc | Co-precipitation method |
| 11739166, | Jul 02 2020 | DAVOL INC | Reactive polysaccharide-based hemostatic agent |
| 7151135, | Dec 18 1995 | ANGIOTECH PHARMACEUTICALS, INC | Crosslinked polymer compositions |
| 7176256, | Dec 18 1995 | ANGIOTECH PHARMACEUTICALS US , INC ; AngioDevice International GmbH | Biocompatible crosslinked composition |
| 7351249, | Nov 06 1998 | Neomend, Inc | Systems, methods, and compositions for achieving closure of suture sites |
| 7883693, | Dec 18 1995 | AngioDevice International GmbH | Compositions and systems for forming crosslinked biomaterials and methods of preparation of use |
| 7883694, | Dec 18 1995 | AngioDevice International GmbH | Method for preventing the formation of adhesions following surgery or injury |
| 8067031, | Apr 28 2004 | AngioDevice International GmbH | Compositions and systems for forming crosslinked biomaterials and associated methods of preparation and use |
| 8197802, | Dec 18 1995 | AngioDevice International GmbH | Method for treating or inhibiting the formation of adhesions following surgery or injury |
| 8377466, | Dec 18 1995 | AngioDevice International GmbH | Adhesive tissue repair patch |
| 8409249, | Nov 06 1998 | Neomend, Inc. | Systems, methods, and compositions for achieving closure of suture sites |
| 8460708, | Apr 28 2004 | AngioDevice International GmbH | Compositions and systems for forming crosslinked biomaterials and associated methods of preparation and use |
| 8481073, | Apr 28 2004 | AngioDevice International GmbH | Compositions and systems for forming crosslinked biomaterials and associated methods of preparation and use |
| 8617584, | Aug 27 1999 | AngioDevice International GmbH | Adhesive tissue repair patch and collagen sheets |
| 9101505, | Apr 27 2006 | BRS Holdings, LLC | Composite stent |
| 9155646, | Apr 27 2006 | BRS Holdings, LLC | Composite stent with bioremovable ceramic flakes |
| 9353218, | Sep 17 2004 | ANGIOTECH PHARMACEUTICALS, INC | Kit for multifunctional compounds forming crosslinked biomaterials |
| RE38827, | Jul 27 1994 | Neomend, Inc | Adhesive sealant composition |
| Patent | Priority | Assignee | Title |
| 2485512, | |||
| 2541804, | |||
| 2688610, | |||
| 2712672, | |||
| 2847713, | |||
| 2897547, | |||
| 3271496, | |||
| 4101380, | Jun 12 1975 | Research Products Rehovot Ltd. | Process for the cross-linking of proteins |
| 4163097, | Jun 18 1975 | ROHNER AG | Crosslinkable polymeric compounds |
| 4323486, | Nov 12 1979 | Teijin Limited | Albumin-fixed resin, production thereof, and therapeutical use thereof |
| 4339295, | Dec 20 1978 | The United States of America as represented by the Secretary of the | Hydrogel adhesives and sandwiches or laminates using microwave energy |
| 4356819, | Mar 21 1979 | ADVANCE TAPES U K LIMITED, | Article of manufacture having adhesive properties |
| 4377572, | Feb 15 1979 | Immuno Aktiengesellschaft fur chemisch-medizinische Produkte | Tissue adhesive |
| 4414976, | Feb 15 1979 | Immuno Aktiengesellschaft fur chemischmedizinische Produkte | Tissue adhesive |
| 4416814, | Oct 18 1978 | ESSILOR INTERNATIONAL ESSILOR | Protein polymer hydrogels |
| 4439322, | Jul 02 1980 | Toray Industries, Inc. | Polymethyl methacrylate membrane |
| 4606337, | Apr 19 1982 | SERAPHARM GMBH & CO KG | Resorptive sheet material for closing and healing wounds and method of making the same |
| 4609546, | Jun 24 1982 | Japan Chemical Research Co., Ltd. | Long-acting composition |
| 4670417, | Jun 19 1985 | Ajinomoto Co., Inc. | Hemoglobin combined with a poly(alkylene oxide) |
| 4692462, | Mar 18 1985 | Menley & James Laboratories, Ltd. | Compositions and method of controlling transdermal penetration of topical and systemic agents |
| 4814120, | Feb 21 1984 | BASF Beauty Care Solutions France SAS | Process for the preparation of collagen tubes |
| 4818542, | Nov 14 1983 | The University of Kentucky Research Foundation | Porous microspheres for drug delivery and methods for making same |
| 4839345, | Mar 09 1985 | Nippon Oil and Fats Co., Ltd. | Hydrated adhesive gel and method for preparing the same |
| 4851513, | Sep 06 1985 | Minnesota Mining and Manufacturing Company | Viscoelastic collagen solution for opthalmic use and method of preparation |
| 4897268, | Aug 03 1987 | Southern Research Institute | Drug delivery system and method of making the same |
| 4898734, | Feb 29 1988 | Massachusetts Institute of Technology | Polymer composite for controlled release or membrane formation |
| 4909251, | May 31 1988 | Immuno Aktiengesellschaft fur chemisch-medizinische Produkte | Tissue adhesive |
| 4952403, | Jun 19 1987 | President and Fellows of Harvard College | Implants for the promotion of healing of meniscal tissue |
| 4997443, | Aug 26 1985 | SOMATIX THERAPY CORPORATION, A CORP OF DE | Transplantable artificial tissue and process |
| 5017556, | Nov 04 1986 | Genentech, Inc. | Treatment of bleeding disorders using lipid-free tissue factor protein |
| 5081295, | Mar 04 1988 | XOMA Corporation | Activated polyers and conjugates thereof |
| 5089261, | Jan 23 1989 | Chiron Corporation | Preparation of a polymer/interleukin-2 conjugate |
| 5091176, | Nov 02 1988 | Hampshire Chemical Corp | Polymer-modified peptide drugs having enhanced biological and pharmacological activities |
| 5112615, | Aug 03 1988 | BETH ISRAEL DEACONESS MEDICAL CENTER, INC , THE | Soluble hirudin conjugates |
| 5118794, | Apr 14 1988 | NOVOZYMES DELTA LIMITED | Process for stabilizing human albumin solutions and the solution obtained |
| 5122614, | Apr 19 1989 | ENZON, INC , A CORP OF NJ | Active carbonates of polyalkylene oxides for modification of polypeptides |
| 5149543, | Oct 05 1990 | MASSACHUSETTS INSTITUTE OF TECHNOLOGY, A CORP OF MA | Ionically cross-linked polymeric microcapsules |
| 5153174, | Oct 30 1989 | UNION CARBIDE CHEMICALS AND PLASTICS COMPANY INC | Polymer mixtures useful in skin care |
| 5162430, | Nov 21 1988 | AngioDevice International GmbH | Collagen-polymer conjugates |
| 5169627, | Oct 28 1991 | Mount Sinai School of Medicine of the City University of New York | Oral pharmaceutical composition containing a polyethylene glycol-immunoglobulin G conjugate for reconstitution of secretory immunity and method of reconstituting secretory immunity |
| 5209776, | Jul 27 1990 | TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF YORK, THE | Tissue bonding and sealing composition and method of using the same |
| 5214131, | May 06 1988 | Sumitomo Pharmaceuticals Company, Limited | Polyethylene glycol derivatives, modified peptides and production thereof |
| 5219564, | Jul 06 1990 | ENZON, INC | Poly(alkylene oxide) amino acid copolymers and drug carriers and charged copolymers based thereon |
| 5232984, | Oct 15 1990 | The Board of the Regents the University of Texas | Biocompatible microcapsules |
| 5235041, | Dec 28 1990 | Protein Polymer Technologies, Inc. | Purification of structurally ordered recombinant protein polymers |
| 5243038, | Nov 04 1986 | PROTEIN POLYMER TECHNOLOGIES, INC | Construction of synthetic DNA and its use in large polypeptide synthesis |
| 5264214, | Nov 21 1988 | AngioDevice International GmbH | Composition for bone repair |
| 5278063, | Sep 28 1989 | BOARD OF REGENTS, THE UNIVERSITY OF TEXAS SYSTEM, | Chemical modification of promote animal cell adhesion on surfaces |
| 5281698, | Jul 23 1991 | Chiron Corporation | Preparation of an activated polymer ester for protein conjugation |
| 5286637, | Aug 07 1989 | Debio Recherche Pharmaceutique SA | Biologically active drug polymer derivatives and method for preparing same |
| 5292362, | Jul 27 1990 | TRUSTEES OF COLUMBIA UNIVERSITY IN THE CITY OF YORK, THE | Tissue bonding and sealing composition and method of using the same |
| 5292802, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Collagen-polymer tubes for use in vascular surgery |
| 5306500, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Method of augmenting tissue with collagen-polymer conjugates |
| 5321095, | Feb 02 1993 | ENZON, INC | Azlactone activated polyalkylene oxides |
| 5324775, | Nov 21 1988 | AngioDevice International GmbH | Biologically inert, biocompatible-polymer conjugates |
| 5324844, | Apr 19 1989 | Enzon, Inc. | Active carbonates of polyalkylene oxides for modification of polypeptides |
| 5328955, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Collagen-polymer conjugates |
| 5330911, | Sep 28 1989 | Board of Regents, The University of Texas System | Surfaces having desirable cell adhesive effects |
| 5334191, | May 21 1992 | POPPAS, DIX P ; SCHLOSSBERG, STEVEN M ; CHOMA, THEODORE J ; KLIOZE, SCOTT D | Laser tissue welding control system |
| 5349001, | Jan 19 1993 | ENZON, INC | Cyclic imide thione activated polyalkylene oxides |
| 5349052, | Oct 20 1988 | PolyMASC Pharmaceuticals plc | Process for fractionating polyethylene glycol (PEG)-protein adducts and an adduct for PEG and granulocyte-macrophage colony stimulating factor |
| 5376375, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Method of augmenting tissue using collagen-polymer conjugates |
| 5380536, | Oct 15 1990 | The Board of Regents, The University of Texas System | Biocompatible microcapsules |
| 5385606, | Jul 06 1992 | HEALTHCARE FINANCIAL SOLUTIONS, LLC, AS SUCCESSOR AGENT | Adhesive composition and method |
| 5405877, | Jan 19 1993 | Enzon, Inc. | Cyclic imide thione activated polyalkylene oxides |
| 5409481, | May 21 1992 | Laserscope | Laser tissue welding control system |
| 5410016, | Oct 15 1990 | BOARD OF REGENTS UNIVERSITY OF TEXAS SYSTEM, THE | Photopolymerizable biodegradable hydrogels as tissue contacting materials and controlled-release carriers |
| 5413791, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Collagen-polymer conjugates |
| 5417982, | Feb 17 1994 | CENTRUM BIOTECHNOLOGIES INC | Controlled release of drugs or hormones in biodegradable polymer microspheres |
| 5444154, | Dec 26 1991 | SILTECH CORP | Crosslinked protein polymers as humectants |
| 5446091, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Collagen-polymer conjugates containing an ether linkage |
| 5455027, | Jul 06 1990 | Enzon, Inc. | Poly(alkylene oxide) amino acid copolymers and drug carriers and charged copolymers based thereon |
| 5462990, | Aug 05 1991 | Board of Regents, The University of Texas System | Multifunctional organic polymers |
| 5468505, | Feb 28 1992 | Board of Regents, The University of Texas System | Local delivery of fibrinolysis enhancing agents |
| 5475052, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Collagen-synthetic polymer matrices prepared using a multiple step reaction |
| 5476653, | Jun 17 1992 | Amgen Inc. | Polyoxymethylene-oxyethylene copolymers in conjuction with biomolecules |
| 5482996, | Dec 08 1993 | University of Pittsburgh | Protein-containing polymers and a method of synthesis of protein-containing polymers in organic solvents |
| 5490984, | Feb 28 1992 | ANGIOTECH BIOMATERIALS CORPORATION | Use of injectable biomaterials for the repair and augmentation of the anal sphincters |
| 5496712, | Nov 06 1990 | SPINE WAVE, INC | High molecular weight collagen-like protein polymers |
| 5496872, | Jul 21 1993 | Imedex | Adhesive compositions for surgical use |
| 5508060, | Feb 11 1993 | Minnesota Mining and Manufacturing Company | Method of polymer impregnation |
| 5514379, | Aug 07 1992 | The General Hospital Corporation; General Hospital Corporation, The | Hydrogel compositions and methods of use |
| 5527856, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Method of preparing crosslinked biomaterial compositions for use in tissue augmentation |
| 5529914, | Aug 05 1991 | BOARD OF REGENTS, THE | Gels for encapsulation of biological materials |
| 5543441, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Implants coated with collagen-polymer conjugates |
| 5550187, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Method of preparing crosslinked biomaterial compositions for use in tissue augmentation |
| 5552452, | Mar 15 1993 | Arch Development Corp | Organic tissue glue for closure of wounds |
| 5565519, | Nov 21 1988 | AngioDevice International GmbH | Clear, chemically modified collagen-synthetic polymer conjugates for ophthalmic applications |
| 5567422, | Feb 02 1993 | Enzon, Inc. | Azlactone activated polyalkylene oxides conjugated to biologically active nucleophiles |
| 5567435, | Feb 28 1992 | Board of Regents, The University of Texas System | Photopolymerizable biodegradable hydrogels as tissue contacting materials and controlled-release carriers |
| 5567440, | Oct 15 1990 | Board of Regents, The University of Texas System | Methods for modifying cell contact with a surface |
| 5573934, | Apr 20 1992 | BOARD OF REGENTS UNIVERSITY OF TEXAS SYSTEM, THE | Gels for encapsulation of biological materials |
| 5580923, | Mar 14 1995 | ANGIOTECH PHARMACEUTICALS, INC | Anti-adhesion films and compositions for medical use |
| 5605938, | May 31 1991 | TRIAD, LLC | Methods and compositions for inhibition of cell invasion and fibrosis using dextran sulfate |
| 5612050, | Mar 23 1993 | Focal, Inc | Apparatus and method for local application of polymeric material to tissue |
| 5614587, | Nov 21 1988 | AngioDevice International GmbH | Collagen-based bioadhesive compositions |
| 5626863, | Feb 28 1992 | Board of Regents, The University of Texas System | Photopolymerizable biodegradable hydrogels as tissue contacting materials and controlled-release carriers |
| 5627233, | Oct 15 1990 | Board of Regents, The University of Texas System | Multifunctional organic polymers |
| 5637749, | Dec 22 1992 | Enzon, Inc. | Aryl imidate activated polyalkylene oxides |
| 5641483, | Jun 07 1995 | Wound healing formulations containing human plasma fibronectin | |
| 5643464, | Nov 21 1988 | AngioDevice International GmbH | Process for preparing a sterile, dry crosslinking agent |
| 5662712, | Apr 28 1993 | Focal, Inc | Apparatus for intraluminal photothermoforming |
| 5702715, | Oct 27 1995 | Drying Technology | Reinforced biological sealants |
| 5733563, | Dec 01 1993 | RBA PHARMA INC | Albumin based hydrogel |
| 5739208, | Nov 12 1993 | Nektar Therapeutics | Isolatable, water soluble, and hydrolytically stable active sulfones of poly(ethylene glycol) and related polymers for modification of surfaces and molecules |
| 5744545, | Nov 21 1988 | ANGIOTECH PHARMACEUTICALS US , INC | Biocompatible adhesive compositions |
| 5808096, | Apr 19 1989 | Enzon, Inc. | Process for preparing active carbonates of polyalkylene oxides for modification of polypeptides |
| 5834274, | Apr 20 1992 | Board of Regents, The University of Texas System | Gels for encapsulation of biological materials |
| 5874537, | Jan 29 1991 | C R BARD, INC | Method for sealing tissues with collagen-based sealants |
| 5895412, | Oct 11 1995 | Baxter International Inc; BAXTER HEALTHCARE S A | Device and method for sealing tissue |
| 5900461, | Nov 12 1993 | Nektar Therapeutics | Isolatable, water soluble, and hydrolytically stable active sulfones of poly(ethylene glycol) and related polymers for modification of surfaces and molecules |
| 5919455, | Oct 27 1993 | Enzon, Inc. | Non-antigenic branched polymer conjugates |
| EP194807, | |||
| EP225162, | |||
| EP454373, | |||
| FR2551660, | |||
| GB579004, | |||
| JP4146218, | |||
| JP6233855, | |||
| WO9013540, | |||
| WO9202238, | |||
| WO9403155, | |||
| WO9401508, | |||
| WO9420133, |
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