Characterization of Polydopamine Crosslinked Tilapia Gelatin-Chitosan Scaffolds in Replacing Mammalian Gelatins for Skin Tissue Application

The blend of mammalian gelatin and chitosan as scaffolds has been widely researched for skin treatment and is considered a superior alternative for skin graft replacements. However, the use of mammalian gelatin raises issues related to halal status and safety concerns. As an alternative, marine gelatins have been utilized as halal replacements for non-halal gelatins. However, marine gelatins have notable limitations, such as a low denaturation temperature and poor stability in aqueous conditions. Therefore, additional biomaterials like chitosan and crosslinkers such as polydopamine are necessary to improve the stability of fish gelatin. This study aims to characterize polydopamine crosslinked tilapia gelatin-chitosan bio-composites (TG-C-Pdop) as a potential replacement for mammalian gelatins in skin tissue applications. The fabrication of samples was done by electrospinning gelatin solutions (20% w/v) and chitosan (5% w/v) composite solutions with a volume ratio of 8:2 (TG-C), and polydopamine (0.5 mL, 2 mg/mL) crosslinked gelatin (20% w/v)- and chitosan (5% w/v) with a volume ratio of 8:2 (TG-C-Pdop). Fourier Transform Infrared with Attenuated Total Reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM), and water contact angle (WCA) measurements were then used to characterize the resulting samples. TG-C-Pdop had an improved fiber diameter of 0.518 ± 0.108 µm compared to other samples as indicated by morphological studies using SEM. Due to the incorporation of chitosan and polydopmine in the gelatin sample, FTIR-ATR results showed shifts in crystalline bands at 1050-1200 cm⁻¹. In addition, lower and consistent water contact angle readings were observed in the TG-C-Pdop scaffold also exhibited lower and more consistent water contact angle readings compared to other samples. In summary, the polydopamine crosslinked tilapia gelatin-chitosan scaffold demonstrates considerable promise for substituting mammalian gelatins in skin tissue engineering endeavors.