Preparation of Anti-bacterial Biocomposite Nanofibers Fabricated by Electrospinning Method

Abstract

Developing technology and increasing the number of living creatures on Earth increasethe demand for biomaterials each passing day. Recently, biocomposites and biodegradablebiomaterials have begun to attract attention in many areas of use. Electrospinning technique ispreferred as a quite consolidated technique in the production of outstanding polymer and/ornanofiber matrixes. However, obtained biocomposite nanofibers can cause microbiologicalinfections during or after their usage. Therefore, it is very important that such materials havecontrolled antibacterial properties. In this study, Hydroxyapatite (HAp), known as biocompatibleand bioactive, was firstly synthesized by wet precipitation method. Molecular structure of obtainedHAp particles was researched by Fourier Transform Infrared Spectroscopy (FT-IR), its crystalstructure was analyzed by X-ray Diffraction analysis (XRD) and its morphology was investigated byScanning Electron Microscopy (SEM). HAp particles were combined with a mixture of biodegradablepolylactic acid (or polylactide, PLA) and polycaprolactone (PCL) and biocomposite nanofibers wereprepared by electrospinning method by loading chitosan and /or silver-based inorganicantimicrobial agent in different proportions to this composite structure. Molecular structure of PLAPCL polymer matrix was investigated by FT-IR analysis. The obtained biocomposites arecharacterized morphology (SEM analysis), thermal behavior (TGA analysis) and mechanicalproperties. In vitro degradation test is performed to evaluate anti-bacterial biocomposite nanofibers biodegradability. The anti-bacterial efficiency of biocomposite nano-fibers containing chitosanand/or Ag+ in different proportions was investigated against Escherichia coli (Gram-negative) andStaphylococcus aureus (Gram-positive) bacteria. The results showed increasing mechanicalproperties and thermal stability. Biocomposite nano-fibers containing 1% chitosan and 0.25% Ag+were found to have ≥4.78 log reduction and ≥99.99% reduction in the bacterial population againstthe tested bacterial species and showed strong antibacterial properties. It was also observed thatthe combination of Ag+ and chitosan may show synergistic effects. The results of the study confirmthe great potential of biodegradable, biocompatible and bioactive fibers for antibacterialapplication.