Ag-HA膜的结晶状况对其抗菌性能的影响

以离子束增强沉积(IBAD)镀膜方法,在Ti6AL4V骨植入材料上镀羟基磷灰石(HA)膜.将镀HA的Ti6AL4V在室温下置入100ppm的AgNO3溶液中浸泡48小时,银离子通过离子交换过程进入HA膜.含银的HA(Ag-HA)膜具有抗大肠杆菌和金黄色葡萄球菌的能力.经研究发现,晶态Ag-HA膜抗菌性能颇佳,与此相反,在非晶态的磷酸钙上细菌生长良好.结晶状况对其抗菌性能有重要影响.结晶较好的HA膜有利于Ag+与晶态HA中的Ca2+进行离子交换而进入HA膜,在一定条件下Ag+从晶格中释放出来,起到抗菌作用.

INFLUENCE OF ORYSTALLIZATION OF Ag-HA FILM ON ITS ANTIMICROBIAL EFFECT

A hydroxyapatite (HA) layer coated on implant material Ti6Al4V was prepared by ion beam assisted deposition (IBAD). By immersing HA coated Ti6Al4V in 100 ppm AgNO_3 solution at room temperature for 48 hrs, the silver ions were incorporated into HA coatings through an ion exchange process. Antimicrobial effects against Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) were observed in silver loaded HA (Ag-HA) coatings. The strong antimicrobial phenomenon was found in crystallized Ag-HA coatings; in comparison, bacteria grew well on the samples coated with amorphous calcium phosphate. The crystallization state of calcium phosphate was an important factor affecting its antimicrobial ability. Higher degree of crystallization led to an effective ion exchange of Ag~ with Ca~(2 ) in HA and easy release of Ag~ from HA, therefore also contributed to the strong antimicrobial effects of Ag-HA.