光谱法研究槲皮苷与人血清白蛋白的相互作用

目的 研究槲皮苷与人血清白蛋白（HSA）的相互作用，并探讨葡萄糖对二者结合的影响。方法 应用光谱法研究槲皮苷与HSA的作用机制，以双对数方程和能量转移原理计算槲皮苷与HSA的结合常数、结合位点数和结合距离；根据热力学参数判断二者的作用力类型；用同步荧光光谱考察槲皮苷对HSA构象的影响；观察葡萄糖浓度对反应结合常数和结合位点数的影响。结果 槲皮苷对HSA的荧光猝灭过程为生成复合物的静态猝灭；结合常数和结合位点数随温度的升高而降低；结合距离小于7 nm；二者主要以疏水作用力相结合；槲皮苷与HSA的相互作用改变了色氨酸残基所处的微环境；葡萄糖的加入使结合常数和结合位点数均增加。结论 槲皮苷能与HSA结合并改变HSA的构象，生理浓度的葡萄糖可增加槲皮苷与HSA的结合常数和结合位点数。

Spectroscopic study on interaction of quercitrin with human serum albumin

Objective To study the preparation of sinomenine hydrochloride (SH) loaded nano flexible liposomes and investigate the mechanism of the flexible liposomes for enhanced in vitro transdermal drug delivery. Methods The SH loaded nano flexible liposomes were prepared by film dispersion method, and the effects of concentration of phosphatidylcholine (PSC), cholesterol (CH), and propyleneglycol (PG) on the entrapment efficiency of SH were also investigated. The SH content was determined by HPLC. The physical property was evaluated by the atomic force microscope (AFM), transmission electron microscope (TEM) and photon correlation spectrometer (PCS). The side-by-side diffusion cells were used to evaluate transdermal delivery of SH by nano flexible liposomes. At the end of the transdermal experiment, the treated skin was carefully observed by scanning electron microscopy (SEM). Results The SH loaded nano flexible liposomes were prepared by film dispersion method with the PSC (3%), CH (0.02%), and PG (25%); The SH entrapment efficiency was (66 ± 2.3)%. The prepared nano flexible liposomes had a closed spherical or elliptical shape showed by AFM images, the TEM images appeared as multi-lamellar vesicles. The calculated mean size was (170 ± 26) nm, the zeta potential values of ? (43 ± 3.4) mV. The SH loaded nano flexible liposomes caused the structure of stratum corneum (SC) layer disturbed and disordered the intercorneocyte domain wider, this increased the skin permeability of drug. Conclusion The SH loaded nano flexible liposomes are obviously resulted in a remarkable enhancement of the SH transdermal drug delivery, which could act as a new nanodimensional vehicle for transdermal delivery of SH.