【摘要】 应用13C -CP/MAS和DSC方法研究蟾毒灵与磷脂膜相互作用的热致相变特性及动力学特性。DSC曲线表明蟾毒灵使磷脂膜相变温度降低 ,吸热峰变宽。13C -CP/MAS谱表明磷脂膜的NMR信号峰化学位移随温度稍有变化 ,提示磷脂膜在液晶态脂肪烃链有不同程度的反 -旁式异构化。含蟾毒灵的EPC脂双层NMR谱 ,随温度升高有蟾毒灵信号峰出现 ,EPC脂双层分子内各部分的信号峰强度和峰形变化明显 ,说明脂双层分子内各部分的流动性有差异 ,有蟾毒灵插入EPC脂双层内。更多还原

【Abstract】 Using high-resolution solid-state 13C-NMR and differential scanning calorimetry(DSC),the thermotropic and dynamic properties of bufalin in egg phosphatidylcholine(EPC)liposome model membranes were studied. The solid-state 13C-NMR, included cross polarization(CP) and magic angle spinning(MAS). DSC as a bulk method showed that bufalin lowered the main phase transition temperatrue and broadened the phase transition peak. 13C-CP/MAS experiments revealed that the chemical shift varied with temperature, indicating different degrees of trans-gauche isomerization in the lipid acyl chains when the bilayer is in the liquid crystalline phase; the specific peaks disappeared in the 13C-CP/MAS spectra when bufalin was present in preparation, indication a different mobility of the corresponding molecular moiety in phospho-lipid bilayer; the changes of relative peak intensitied also confirmed the incorporation of bufalin in the bilayer. These results suggest bufalin causes more perturbation in the lipid bilayer.更多还原