title: Influence on the physicochemical properties of fish collagen gels using self-assembly and simultaneous cross-linking with the N-hydroxysuccinimide adipic acid derivative.
abstract: Collagen gels from Southern catfish (Silurus meridionalis Chen) skins were prepared via the self-assembly of collagen molecules and simultaneous cross-linking with the N-hydroxysuccinimide adipic acid derivative (NHS-AA). The doses of NHS-AA were converted to [NHS-AA]/[NH2] ratios (0.025-1.6, calculated by the [active ester group] of NHS-AA and [ε-NH2] of lysine and hydroxylysine residues of collagen). When the ratio < 0.05, collagen gels were formed by collagen molecule self-assembly, resulting in the opalescent appearance of collagen gels and the characteristic D-periodicity of partial collagen fibrils, the collagen gel ([NHS-AA]/[NH2] = 0.05) displayed a small increase in denaturation temperature (Td, 42.8 °C), remaining weight (12.59%), specific water content (SWC 233.7) and elastic modulus (G' 128.4 Pa) compared with uncross-linked collagen gel (39.1 °C, 9.12%, 222.4 and 85.4 Pa, respectively). As the ratio > 0.05, disappearance of D-periodicity and a gradual change in appearance from opalescent to transparent suggested that the inhibition of NHS-AA in the self-assembly of collagen molecules was more obvious. As a result, the collagen gel ([NHS-AA]/[NH2] = 0.2) had the lowest Td (35.8 °C), remaining weight (7.96%), SWC (130.9) and G' (31.9 Pa). When the ratio was 1.6, the collagen molecule self-assembly was markedly suppressed and the formation of collagen gel was predominantly via the covalent cross-linking bonds which led to the transparent appearance, and the maximum values of Td (47.0 °C), remaining weight (45.92%) and G' (420.7 Pa) of collagen gel. These results indicated that collagen gels with different properties can be prepared using different NHS-AA doses.
authors.affiliation: The Key Laboratory of Leather Chemistry and Engineering of Ministry of Education, Sichuan University , Chengdu, PR China and.
authors.forename: Lirui
authors.initials: L
authors.lastname: Shen
authors.forename: Zhenhua
authors.initials: Z
authors.lastname: Tian
authors.forename: Wentao
authors.initials: W
authors.lastname: Liu
authors.forename: Guoying
authors.initials: G
authors.lastname: Li
mesh_terms: D000272:Adipates / Q000737:chemistry / Q000494:pharmacology*; D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry / Q000378:metabolism*; D055598:Chemical Phenomena; D003094:Collagen / Q000737:chemistry / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000737:chemistry / Q000494:pharmacology*; D055119:Elastic Modulus / Q000187:drug effects; D005109:Extracellular Matrix / Q000378:metabolism; D005399:Fishes; D005782:Gels / Q000737:chemistry; D013388:Succinimides / Q000737:chemistry*; D013696:Temperature
chemical_list: D000272:Adipates; D001672:Biocompatible Materials; D003432:Cross-Linking Reagents; D005782:Gels; D013388:Succinimides; C029900:adipic acid; D003094:Collagen; C001426:N-hydroxysuccinimide
keywords: Collagen gel; N-hydroxysuccinimide adipic acid derivative Southern catfish; cross-linking; properties; self-assembly