Polyurethane/halloysite nano tubes/sericin based electrospun nanocomposite for sustained drug release

In this study, the feasibility of the production of electrospun nanofibre composite mainly for biomedical applications is reported. Biocompatible polyether-based polyurethane, natural proteinaceous polymer silk sericin (SS) and natural inorganic nanoclay halloysite as a drug carrier with a model drug chlorhexidine acetate were used to produce nanofibres by electrospinning technique. Sericin was extracted from Bombyx mori silk cocoons by high pressure high temperature (HT-HP) degumming. Chlorhexidine acetate (CA), an antimicrobial agent, was loaded into halloysite nanotubes (HNTs) at different weight ratios, and 1:1 weight ratio showed the maximum loading which was confirmed by TGA and XRD analysis. Electrospinning of polymer solution with different compositions of polyurethane, sericin, CA and CA-HNTs was conducted at 10% w/v concentration, 20 kV voltage, 15 μl min−1 flow rate and 10 cm distance which resulted in the formation of bead-free uniform fibres. Antimicrobial activity of nanofibrous webs was evaluated by the disc diffusion method (AATCC 90) and it was found that CA and CA-HNT loaded nanofibres show sustained antibacterial action against both the Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. The CA-HNT and sericin/CA-HNT loaded nanofibres showed controlled release of CA. In addition, the cytocompatibility assessment of developed nanofibrous composites showed good biocompatibility. Hence the produced composite nanofibre can serve as an excellent material for sustained drug release for various biomedical applications.