乙酰普鲁兰纳米粒子与牛血清白蛋白的相互作用

Interaction between bovine serum albumin and pullulan acetate nanoparticles

目的考查乙酰普鲁兰纳米粒子（PANs）与牛血清白蛋白（BSA）的相互作用，为研究PANs体内药代动力学特征奠定基础。方法将不同浓度的PANs溶液和BSA溶液混合，应用荧光法和圆二色谱（CD）法考察二者间的相互作用，计算PANs与BSA结合的缔合常数（Kq），观测PANs-BSA抗尿素变性的作用。结果PANs对BSA荧光的影响具有浓度相关性，PANs溶液（0．015～0．25mg／m1）与BSA（O．25mg／m1）的缔合常数Kq从2．64×10^4增高至3．55×10^5；在尿素或加热条件下，PANs-BSA溶液和BSA溶液的cD光谱具有相似的变化趋势。结论PANs对BSA的荧光光谱具有显著影响，但PANs未影响尿素和高温对BSA的变性作用。

Objective To investigate the interaction of pullulan acetate nanoparticles （PANs） and bovine serum albumin （BSA）, and to provide the basis for in vivo pharmacokinetic study of PANs. Methods Mixed solutions of different concentration of PANs and BSA solution was prepared, the interaction was studied by fluorescence quenching method and circular dichroism （CD） measurement. Apparent quenching constant （Kq） between the PANs and BSA was calculated, and the anti-stress effect induced by urea and heating of PANs-BSA solution was observed. Results The fluorescence spectrum of BSA was affected by PANs on density-related manner, and Kq calculated by the modified Stern-Volmer plot increased from 2.64～104 to 3.55～105 with the concentration of PANs increased from 0.015 mg/ml to 0.25 mg/ml. With the denaturation of urea or heating, the CD spectrum of PANs-BSA and free BSA had the similar variation tendency. Conclusions The fluorescence spectrum display results show that interaction between PANs and BSA exists, but the interaction does not protect the BSA from degeneration by urea and heating.