In situ ATR-FTIR was used to study the interaction of bovine serum albumin（BSA） and hydroxyapatite（HA） in this work.Both on the electrochemically deposited HA and self assemblied titanate nanotubes（TNT） substrates,the adsorption of BSA increases with the increase of time,and its adsorption on HA surface is much larger than that on TNT surface,implying that HA has a good biocompatibility as a biomaterial.It is indicated that Ca2+ plays an essential role in the protein absorption on the HA surface,due to that BSA is negatively charged,and it is able to combine with cation locations in HA particles by electrostatic forces.It is found that,when reacting with BSA,the phosphate band of HA in solution shifts to higher wavenumbers,indicating that PO3-4 can also be an adsorption site for BSA.The spectroscopic study on the interaction between HA and BSA will be helpful for further understanding the nano hydroxyapatite bioproperties on molecular level.
