Abstract: The interactions between phosphatidylcholine (PC) and bovine serum albumin (BSA) were studied by FT-IR and FT-Raman spectroscopies, then the influence of lanthanide ion Eu3＋ on the PC/BSA mixture system was discussed. In the region of 900～1300 cm－1, FT-IR spectra showed that the bands of P=O, P-O-C and C－O of the PC/BSA mixture were shifted compared with the corresponding bands of pure PC and BSA, and the more content of BSA (relative to the content of PC) the greater shift was observed. The curve-fitting result of amide I band indicated that an increase of α-helix fragments in the PC/BSA mixture. FT-Raman spectra showed that the CH stretching bands in the PC/BSA mixture were varied, which indicated a disturbance of PC′s long chains in the mixture system. After Eu ion was added into the PC/BSA system, the P=O stretching vibration bands in FT-IR spectra shifted from 1241 to 1208 cm－1. This helped us to conclude that the Eu ions bind to the P=O group in the PC/BSA mixture.

Key words: FT-IR, FT-Raman, Phosphatidylcholine, BSA