Effect of silver content on the antibacterial and bioactive properties of silver-substituted hydroxyapatite.
The long-term success of a biomaterial used during surgery may be compromised by infection. A possible effective solution is to make the biomaterial osteoconductive and antibacterial. A range of silver-substituted hydroxyapatite (AgHA) of up to 1.1 wt. % of Ag was synthesized. AgHA displayed a rod-like morphology of dimensions ~50 nm in length and ~15 nm in width. Phase-pure AgHA was demonstrated in the X-ray diffraction patterns and Fourier transform infrared spectroscopy spectra. Comparing with hydroxyaptite (HA), 0.5AgHA exhibited a 3-log reduction in the number of bacteria. Diffusion of the entrapped Ag(+) ions towards the crystal structure surface was revealed by an increase of 6 at. % Ag in the X-ray photoelectron spectroscopy results. Furthermore, less than 0.5 ppm of Ag(+) ions being released from 0.5AgHA into the deionized water medium was evidenced from the inductively coupled plasma mass spectrometry results. AgHA produced by co-precipitation gave rise to minimal release of Ag(+) ions. It was hypothesized that the diffused surface Ag(+) ions damaged the bacteria cell membrane and impede its replication. With the culturing time, significant increase in the number of human mesenchymal stem cells (p < 0.05) was demonstrated on 0.5AgHA.
Department of Mechanical Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117 576, Singapore.
Poon Nian
PN
Lim
Erin Yiling
EY
Teo
Bow
B
Ho
Bee Yen
BY
Tay
Eng San
ES
Thian
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology; D001672:Biocompatible Materials / Q000737:chemistry* / Q000494:pharmacology; D002478:Cells, Cultured; D006801:Humans; D006882:Hydroxyapatites / Q000737:chemistry*; D008422:Materials Testing; D053768:Metal Nanoparticles / Q000737:chemistry / Q000648:ultrastructure; D016348:Osseointegration; D012834:Silver / Q000737:chemistry* / Q000494:pharmacology; D013211:Staphylococcus aureus / Q000187:drug effects; D014961:X-Ray Diffraction
D000900:Anti-Bacterial Agents; D001672:Biocompatible Materials; D006882:Hydroxyapatites; D012834:Silver
antibacterial; bioactivity; hydroxyapatite; mesenchymal stem cell; silver