Long-term antioxidant and ultraviolet light shielding gelatin films for the preservation of leather artifacts

In this study, CA-Gel complexes were prepared by crosslinking gelatin with chlorogenic acid (CA) by EDC/NHS chemistry, and incorporated into gelatin to produce CA-Gel/Gel films for leather artifact preservation. The synthesized CA-Gel complex had a total phenolic content of 139.62 ± 1.8 mg/g. The moisture content of CA-Gel/Gel film is 37.84 % lower than that of Gel film. The addition of CA-Gel complexes enhanced the hydrophobic and antibacterial properties of Gel films. CA-Gel/Gel films showed excellent antioxidant properties, as evidenced by the increase in the DPPH radical scavenging rate from 0 to 98.18 %. Additionally, CA-Gel/Gel films effectively shield UV light, preventing almost the transmission of ultraviolet rays. Notably, CA-Gel/Gel films maintain their antioxidant properties and UV light shielding after one month at ambient temperature. Therefore, their long-term antioxidant and UV light shielding properties were indicated. In addition, the UV light aging tests were carried out on leathers with and without CA-Gel/Gel film coverage. The results showed that CA-Gel/Gel films effectively preserved the original color of leathers, with no changes in their random coil structure before and after UV light irradiation. This work emphasizes the potential use of CA-Gel/Gel films as an innovative protective packaging solution for long-term preservation of leather artifacts.