دانلود رایگان مقاله انگلیسی سنتز هیدروکسی آپاتیت آلاییده مونوفازیک و ارزیابی فعالیت آنتی باکتریال - الزویر 2018

ABSTRACT

The present study aims to synthesized biomaterial that has antibacterial properties. Currently the surgical implants associated infections are a major cause of implant failure. Synthesis of silver doped hydroxyapatite as an antibacterial agent has potential importance to overcome post-surgical infections in a variety of clinical applications. Five silver doped hydroxyapatite Ca10−xAgx(PO4)6(OH)2 (x = 0, 0.1, 0.3, 0.5, 0.7 M) samples were synthesized by precipitation method and sintered at 900 °C to obtain well crystallized structure. No minor phase developed with silver addition, hexagonal hydroxyapatite (JCPDS# 09-432) was the single phase identified in all silver doped hydroxyapatite samples. The lattice parameter a and c changed with increase in silver concentration. The results of in vitro bioactivity revealed the bone bonding ability of silver doped hydroxyapatite samples. The antibacterial test showed that silver doped hydroxyapatite was sensitive to Staphylococcus aureus bacteria. Addition of silver significantly (P < 0.005) increased the antibacterial activity.

4. Conclusion

Monophasic silver doped hydroxyapatite was successfully synthesized by precipitation method and it was confirmed by XRD, FTIR and Raman spectroscopy. The analysis showed that a single phase of hexagonal hydroxyapatite was identified in all silver doped hydroxyapatite specimens with no minor phase, which indicates that Ag+ was well substituted in lattice without disturbing the crystal structure. It was observed that 7% (0.7 M) of Ag+ substituting in the Ca+2 site and sintering at 900 °C are the optimum limit to obtain monophasic hydroxyapatite crystalline structure. In vitro bioactivity test in SBF confirmed the bone-bonding ability of silver doped hydroxyapatite. The antibacterial assays showed that all silver doped hydroxyapatite samples had the bacteria inhibition ability and antibacterial activity increases significantly with increase in concentration of Ag+. The undoped sample had limited antibacterial activity against Staphylococcus aureus while addition of Ag+ enhanced antibacterial activity. From the present study it can be suggested that silver doped hydroxyapatite possessing antibacterial activity is a potentially good biomaterial for bone tissue engineering that can limit the risk of post-surgical infections caused by bacteria colonization.