Synthesis of bovine serum albumin-gelatin composite adhesive hydrogels by physical crosslinking

In this work, a series of bovine serum albumin-gelatin (BSA-Gel) adhesive hydrogels were synthesized via non-covalent interactions. We demonstrated possible tuning the properties, microstructure, thermal stability of hydrogels by varying BSA concentration and Gel molecular weight. Two Gel molecular weights were used, which was confirmed using gel permeation chromatography (GPC) (M-1, M-w approximate to 105 kDa, M-2, M-w approximate to 2.9 kDa). The lap shear test showed that adhesive strength of 45% BSA-20% Gel (M-1) and 45% BSA-20% Gel (M-2) on gelatin coated glass slides was 384.4 kPa and 357.9 kPa respectively, which was higher than pure 20% Gel (M-1), 20% Gel (M-2) of 306.1 kPa and 321 kPa respectively. SEM results demonstrated that BSA-Gel (M-1) hydrogels had compact structure, while BSA-Gel (M-2) hydrogels had porous structure. The 45% BSA-20% Gel (M-1) hydrogel was stable more than 10 h at 37 degrees C, which was promising for applications in many biomedical areas such as tissue adhesive, wound dressing and drug delivery.