ABSTRACT
Herein, we report on a robust approach to fabricate antibacterial nanocomposite coating simply by immersing poly(oligo(ethylene glycol) methacrylate) (POEGMA) brush into a silver perchlorate solution without using any external reducing agents. The POEGMA brush of 48.3 nm in thickness is prepared via surface-initiated atom transfer radical polymerization method. Field-emission scanning electron microscope and Raman measurements indicate that silver nanoparticles of 14 â¼ 25 nm in diameter are successfully embedded into the POEGMA brush. Antibacterial activities of the resultant silver-loaded POEGMA brushes against both Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus are measured by zone of inhibition and colony-counting methods, respectively. The results show that the silver-loaded POEGMA coatings exhibit enhanced antibacterial efficiency compared to bare POEGMA brush. In order to elucidate their antibacterial mechanism, silver release behaviors of these silver-loaded POEGMA brushes are monitored via inductively coupled plasma mass spectrometry.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Drug Carriers/chemistry , Polymethacrylic Acids/chemistry , Silver/chemistry , Silver/pharmacology , Drug Liberation , Escherichia coli/drug effects , Metal Nanoparticles/chemistry , Nanocomposites/chemistry , Staphylococcus aureus/drug effectsABSTRACT
The antibacterial carboxymethyl chitosan/ZnO nanocomposite hydrogels were successfully prepared via in situ formation of ZnO nanorods in the crosslinked carboxymethyl chitosan (CMCh) matrix, by treating the CMCh hydrogel matrix with zinc nitrate solution followed by the oxidation of zinc ions with alkaline solution. The resulting CMCh/ZnO hydrogels were characterized by using FTIR spectroscopy, X-ray diffractormetry and scanning electron microscopy (SEM). SEM micrographs revealed the formation of ZnO nanorods in the hydrogel matrix with the size ranging from 190nm to 600nm. The swelling behavior of the prepared nanocomposite hydrogels was also investigated in different pH solutions. The CMCh/ZnO nanocomposite hydrogel showed rather higher swelling behavior in different pH solutions in comparison with neat CMCh hydrogel. Furthermore, the antibacterial activity of CMCh/ZnO hydrogel was studied against Escherichia coli and Staphylococcus aureus by CFU assay. The results demonstrated an excellent antibacterial activity of the nanocomposite hydrogel. Therefore, the developed CMCh/ZnO nanocomposite hydrogel can be used effectively in biomedical field.
