Evaluating the biocompatibility of marine-derived chitosan–collagen polymeric blends for biomedical applications

The capability of biomaterials such as chitosan and collagen to support cell growth and proliferation makes them promising candidates in biomedical applications. Chitosan and collagen from marine world have already been proved to be better alternatives to those from terrestrial world. In the current study, chitosan and collagen were isolated from shrimp shell and fish skin, respectively. The polymers were characterized by ultraviolet-visible spectra analysis, Fourier transform infrared-attenuated total reflectance analysis, CHN analysis, and sodium dodedcyl sulfate polyacrylamide gel electrophoresis analysis. Interpenetrating blends of these polymers were synthesized in the form of films in two different ratios. Glutaraldehyde was used as an additional cross-linker to provide more stability to the blends. The polymeric blends were also characterized by Fourier transform infrared-attenuated total reflectance, scanning electron microscopy analysis, and swelling studies. The biocompatibility evaluation included hemocompatibility and cytocompatibility studies. Fourier transform infrared-attenuated total reflectance analysis of films confirmed the presence of characteristic functional groups and molecular interactions of the two polymers in the two blends. Homogenous blending of the two biopolymers in both film compositions was confirmed by the smooth surface images in scanning electron microscopy analysis. The swelling study revealed that both the films can effectively transfer water across it, hence nutrients and waste materials. During hemocompatibility evaluations, no red blood cell aggregation was observed and both the films adsorbed plasma proteins, predominantly albumin, when they made contact with blood. Although one of the films showed slightly higher hemolysis, the value was within the acceptable range. More than 90% viability obtained in 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay shows the non-toxic nature of the two films. No sign of morphological changes to L929 cells was seen when they were in direct contact with both films. Live/dead assay using acridine orange/ethidium bromide cocktail showed that the films have not induced apoptosis to the L929 cells, which further asserts their biocompatible nature.