Preparation of anti-bacterial biocomposite nanofibers fabricated by electrospinning method

Abstract

Developing technology and increasing the number of living creatures on Earth increase the demand for biomaterials each passing day. Recently, biocomposites and biodegradable biomaterials have begun to attract attention in many areas of use. 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 obtained biocomposites are characterized morphology (SEM analysis), thermal behavior (TGA analysis) and mechanical properties. In vitro degradation test is performed to evaluate anti-bacterial biocomposite nanofibers biodegradability. The anti-bacterial efficiency of biocomposite nano-fibers containing chitosan and/or Ag + in different proportions was investigated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) bacteria. The results showed increasing mechanical properties 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 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.

Effect of Filler Content on the Morphology and Physical Properties of Poly(Lactic Acid)-Hydroxyapatite Composites

“…Figure 6 depicts the plot of the particle fraction as a function of the particle size distribution, and it appears that the average size distribution is between 0.4 and 8 μm. This is consistent with the data provided by Kesmez et al [ 40 ], who indicated the formation of wide agglomerated particles having an average particle size ranging from 1 to 15 μm.…”

Lightweight, Self-Poled, Flexible Piezoelectric Tungsten Disulfide Quantum Dots-Reinforced PVDF-HFP-Based Nanogenerator

“…The WS 2 QDs show the absorption bands at 671 and 928 cm –1 , which appeared due to W–S and S–S bonds, confirming the formation of WS 2 and the peaks that appeared at 1461 and 1645 cm –1 are due to the stretching deformation of the hydroxyl group. The peaks observed at 2922 and 3449 cm –1 were associated with the atmospheric −OH stretching. , …”

“…The peaks observed at 2922 and 3449 cm −1 were associated with the atmospheric −OH stretching. 37,38 The relative amounts of the β phase in pristine and WS 2reinforced PVDF-HFP were analyzed using the relative absorption intensities of β and α phase and the method proposed by Gregorio & Cestari…”

Preserving Intangible Heritage through Tangible Finds: The “Skull with Ears”—St. Luciella ai Librai’s Church (Naples, Italy)

“…2− [36], while the one at 870 cm −1 is associated with the υ 2 symmetric stretching vibrations of carbonate ions, which can be incorporated into the apatites from atmospheric CO 2 [32]. The peak at 3338 cm −1 corresponds to the ion stretching of the OH − , confirming the presence of the hydroxyl group, while the water that is associated with hydroxyapatite can be seen at 3471 and 1641 cm −1 , respectively, corresponding to the stretching and bending vibrations [37][38][39]. These FT-IR ATR analyses could have detected vestigial organic fractions in the samples, such as collagen.…”