Effects of decanoyl group modification and 4S-PEG molecular weight on the physicochemical and biological properties of Alaska pollock gelatin tissue adhesives

Tissue adhesives are widely used for postoperative wound closure and sealing. However, challenges remain regarding adhesive strength, swelling behavior, and biocompatibility. We previously developed tissue adhesives composed of hydrophobically-modified Alaska pollock gelatin and pentaerythritol poly(ethylene glycol) ether tetrasuccinimidyl glutarate (4S-PEG), which demonstrated excellent adhesive strength and biocompatibility. However, the effects of adhesive parameters, such as the molecular weight of 4S-PEG and the degree of hydrophobic modification, on the adhesive characteristics have not yet been determined. In this study, we investigated the effects of the 4S-PEG molecular weight and degree of decanoyl modification on the physicochemical and biological properties of C10-ApGltn/4S-PEG adhesive, including swelling behavior, mechanical strength, burst strength, and biocompatibility. The swelling ratio, tensile strength, and tensile strain of the hydrogels increased with increasing 4S-PEG molecular weight. In contrast, the burst strength increased up to 23 mol% and then decreased. 23C10-ApGltn/4S-PEG10k exhibited biodegradability without inducing severe inflammation and demonstrated excellent physicochemical and biological properties, indicating its suitability for cardiovascular applications.