Application of sustainable marine collagen/cellulose nanofiber Pickering emulsions in skincare: From fishery waste to UV-resistant formulations

Collagen, extracted from Prionace glauca skin waste, exhibits exceptional anti-photoaging biological activity. Herein, a sustainable Pickering emulsion stabilized by Prionace glauca skin collagen/cellulose nanofibers (PGSC/CNFs) was developed to address UV-induced skin damage. PGSC extracted from fishery waste exhibited synergistic interactions with CNFs, demonstrating enhanced thermal stability and interfacial hydrophobicity. At an optimal ratio (0.2 wt% PGSC/0.08 wt% CNFs), the composite achieved ultra-fine emulsion droplets (0.713 ± 0.018 μm) and remained stable after 14 days. The emulsion exhibited exceptional UV-blocking performance (transmittance <0.07 % at 254 nm and 365 nm) and antioxidant activity (DPPH/ABTS scavenging >86 %/92 %). The PGSC/CNFs significantly suppressed UV-induced ROS generation by approximately 40 %, and the Pickering emulsions effectively inhibited pigmentation changes in a porcine skin model after 4 h of irradiation. Biocompatibility was confirmed by low hemolysis (<6 % at 4000 μg/mL). This work transformed marine waste into a bioactive emulsifier, offering a green strategy for multifunctional anti-UV skincare formulations.