Covalent streptavidin immobilization on electrospun poly(m -anthranilic acid)/polycaprolactone nanofibers and cytocompatibility

An electrospun poly(m-anthranilic acid)/poly(ϵ-caprolactone) nanofiber mat was fabricated with functionalization of the surface with streptavidin which can enhance the cell attachment and proliferation. Poly(ϵ-caprolactone) as biodegradable, biocompatible, and electrospinnable polymer was blended with poly(m-anthranilic acid) because of the carboxylic acid (-COOH) groups on its backbone which allow the covalent immobilization of streptavidin onto nanofibers. 1-Ethyl-3-(dimethyl-aminopropyl) carbodiimide hydrochloride/N-hydroxyl succinimide coupling reaction was used for immobilization and the presence of bound protein was investigated by Fourier transform infrared-attenuated total reflection spectroscopy and electrochemical impedance spectroscopy, as well as the confocal microscopy. Human osteoblast-like cells (SaOS₂) were cultured on poly(m-anthranilic acid)/poly(ϵ-caprolactone) and streptavidin-immobilized poly(m-anthranilic acid)/poly(ϵ-caprolactone) nanofibers to evaluate the in vitro biocompatibility of nanofibers. Fluorescence staining of F-actin was performed to observe the cell morphology. The results confirmed the successful immobilization of streptavidin on the nanofibers and streptavidin immobilization enhanced the cell attachment and proliferation onto the poly(m-anthranilic acid)/poly(ϵ-caprolactone) nanofibers.