Agar-based antioxidant composite films incorporated with melanin nanoparticles

Melanin nanoparticles (MNP) were isolated from the sepia ink using a centrifugation method and used as a functional filler for the preparation of agar-based functional films. The MNP were spherical with an average diameter of 95.6 +/- 21.2 nm. Field emission scanning electron microscopy (FE-SEM) and Fourier transform infrared spectroscopy (FTIR) test results indicated that the MNP were well dispersed in agar polymer to form free-standing composite films. The addition of MNP enhanced the UV-blocking, hydrophobicity, mechanical, and water vapor barrier properties of the agar film. Also, the agar/MNP composite films showed a high antioxidant activity comparable to ascorbic acid. The MNP separated from sepia ink can be used as a functional filler to develop antioxidant biopolymer films for food packaging and biomedical applications.