Preparation of anti-bacterial biocomposite nanofibers fabricated by electrospinning method

Developing technology and increasing the number of living creatures on earth increase the demand for biomaterials each passing day. Recently, biocomposite and biodegradable biomaterials have begun to attract attention in many areas of usage. Electrospinning technique is preferred as a quite consolidated technique in the production of outstanding polymer and/or nanofiber matrixes. However, obtained biocomposite nanofibers can cause microbiological infections during or after their usage. Therefore, it is very important that such materials have controlled antibacterial properties. In this study, Hydroxyapatite (HAp), known as biocompatible and bioactive, was firstly synthesized by wet precipitation method. Molecular structure of obtained HAp particles was researched by Fourier Transform Infrared Spectroscopy (FT-IR), its crystal structure was analyzed by X-ray Diffraction analysis (XRD) and its morphology was investigated by Scanning Electron Microscopy (SEM). HAp particles were combined with a mixture of biodegradable polylactic acid (or polylactide, PLA) and polycaprolactone (PCL) and biocomposite nanofibers were prepared by electrospinning method by loading chitosan and /or silver-based inorganic antimicrobial agent in different proportions to this composite structure. Molecular structure of PLA-PCL polymer matrix was investigated by FT-IR analysis. The morphology of the obtained biocomposite nanofibers was examined by SEM. The anti-bacterial efficiency of biocomposite nanofibers containing chitosan and/or Ag+ in different proportions was investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. Biocomposite nanofiber samples containing 1% chitosan and 0.25% Ag+ were found to have ≥4.78 log reduction and ≥99.99% reduction in the bacterial population against the tested bacterial species and showed strong antibacterial properties. It was also observed that the combination of Ag+ and chitosan may show synergistic effects. The results of the study confirm the great potential of biodegradable, biocompatible and bioactive fibers for antibacterial application.