摘要
用电化学石英晶体阻抗法(EQCI)和衰减全反射红外光谱法(FTIR-ATR)研究了牛血清白蛋白(BSA)在纳米生物活性材料TiO_2和羟基磷灰石(HAP)上的吸附行为,获得了BSA吸附过程中电极表面的质量变化和电极/蛋白质界面双电层中电容变化以及BSA构象变化等信息。以2步骤连串反应机理分析BSA吸附动力学。结果表明,BSA在2种电极表面的吸附过程均分为吸附和重排2个过程,BSA在TiO_2上吸附速度慢于在HAP上的吸附,且难达到稳定状态。根据Sauerbrey方程结合Martin方程估算了BSA在TiO_2和HAP上饱和吸附时的表面质量覆盖度,分别为1．12×10^(-6)和1．09×10^(-6)g/cm^2。红外谱图结果还表明,生物材料的表面组成对蛋白质吸附动力学和蛋白质结构变化均有影响。BSA在HAP表面吸附时的响应更大,并对蛋白质二级结构的变化影响更大。
The adsorption of bovine serum albumin （BSA） onto nanocrystalline hydroxyapatite and TiO2 was studied by electrochemical quartz crystal impedance and FTIR-ATR spectroscopy. The response parameters of piezoelectric quartz crystal（PQC） resonance, frequency and the changes in the double electric layer capacitance were obtained during BSA adsorption. The adsorption kinetics was analyzed with a scheme of two consecutive reactions occurring at the interface. The adsorption rate of BSA on TiO2 surface was lower than that on HAP surface. The saturated surface coverages of BSA were respectively 1.09 × 10^-6 and 1.12 × 10^-6 g/cm^2 on HAP and TiO2 calculated via the Sauerbrey＇s equation. FTIR-ATR spectroscopy was used to study the adsorption kinetics and the change of the BSA second order structure. The experimental results show that the structure of the biomaterial affects both the adsorption kinetics and the second order structure of the BSA and the effect of HAP on the BSA adsorption is more notably.
出处
《应用化学》
CAS
CSCD
北大核心
2007年第2期128-133,共6页
Chinese Journal of Applied Chemistry
基金
国家自然科学基金(20335020
20675030)
重大基础研究前期研究专项(2003CCC00700)
湖南省教育厅重点项目资助
