title: Thermal and spectrophotometric studies of new crosslinking method for collagen matrix with glutaraldehyde acetals.
abstract: Despite the many existing crosslinking procedures, glutaraldehyde (GA) is still the method of choice used in the manufacture of bioprosthesis. The major problems with GA are: (a) uncontrolled reactivity due to the chemical complexity or GA solutions; (b) toxicity due to the release of GA from polymeric crosslinks; and (c) tissue impermeabilization due to polymeric and heterogeneous crosslinks formation, partially responsible for the undesirable calcification of the bioprosthesis. A new method of crosslinking glutaraldehyde acetals has been developed with GA in acid ethanolic solution, and after the distribution inside de matrix, GA is released to crosslinking. Concentrations of hydrochloride acid in ethanolic solutions between 0.1 and 0.001 mol/L with GA concentration between 0.1 and 1.0% were measured in an ultraviolet spectrophotometer to verify the presence of free aldehyde groups and polymeric compounds of GA. After these measurements, the solutions were used to crosslink bovine pericardium. The spectrophotometric results showed that GA was better protected in acetal forms for acid ethanolic solution with HCl at 0.003 mol/L and GA 1.0%(v/v). The shrinkage temperature results of bovine pericardium crosslinked with acetal solutions showed values near 85 degrees C after the exposure to triethylamine vapors.
authors: Depto. Quím. Fís. Molec. Inst. Quím. São Carlos, Universidade de São Paulo-Av., Trabalhador São-Carlense, 400, São Carlos CEP 13.566-490 SP, Brazil. sergioy@iqsc.usp.br
authors: Sergio A
authors: SA
authors: Yoshioka
authors: G
authors: G
authors: Goissis
mesh_terms: D000080:Acetals / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D002417:Cattle; D003094:Collagen / Q000737:chemistry* / Q000187:drug effects*; D003432:Cross-Linking Reagents / Q000737:chemistry / Q000494:pharmacology; D004055:Differential Thermal Analysis; D004548:Elasticity; D000431:Ethanol / Q000494:pharmacology; D005976:Glutaral / Q000737:chemistry / Q000494:pharmacology*; D006863:Hydrogen-Ion Concentration; D008954:Models, Biological; D010496:Pericardium / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry; D013056:Spectrophotometry, Ultraviolet; D013696:Temperature; D023822:Tissue Engineering / Q000379:methods; D017155:Wettability / Q000187:drug effects
chemical_list: D000080:Acetals; D003432:Cross-Linking Reagents; D011108:Polymers; D000431:Ethanol; D003094:Collagen; D005976:Glutaral
references: Circulation. 1984 Sep;70(3 Pt 2):I165-8
references: 6744560
references: Artif Organs. 1998 Mar;22(3):210-4
references: 9527281
references: J Cardiovasc Surg (Torino). 1994 Apr;35(2):139-45
references: 8195274
references: Biomaterials. 1991 Oct;12(8):707-14
references: 1799646
references: Anal Biochem. 1992 Feb 14;201(1):94-8
references: 1621967
references: J Thorac Cardiovasc Surg. 1974 Sep;68(3):361-79
references: 4853033
references: Connect Tissue Res. 1982;10(2):201-16
references: 6299648
references: J Biomed Mater Res. 1990 Sep;24(9):1185-201
references: 2120238
references: Connect Tissue Res. 1985;13(2):109-15
references: 3157539
references: Lab Invest. 1985 May;52(5):523-32
references: 3990244
references: J Bioeng. 1978 Apr;2(1-2):1-9
references: 98522