Department of Molecular and Biomolecular Physics, National Institute of Isotopic and Molecular Technologies, 400293 Cluj Napoca, Romania.
J Pharm Biomed Anal. 2013 Jan;72:134-8. doi: 10.1016/j.jpba.2012.09.023. Epub 2012 Oct 4.
The interaction between stavudine, a nucleoside reverse transcriptase inhibitor and human serum albumin (HSA), was investigated by fluorescence quenching technique and isothermal titration calorimetry (ITC). A good linearity of albumin fluorescence quenching in the presence of stavudine was determined. Analyzing these data we obtained for the dissociation constant the value K(d)=(18.18 ± 0.46) × 10(-5)M. However, due to contradictory results obtained in ITC experiments, we checked the fluorescence quenching data for the inner-filter effect, the main confounding factor in the observed quenching. Based on the UV-vis absorption data we have corrected the observed fluorescence intensities and concluded, in accordance with ITC results, that stavudine binding to HSA is negligible and the observed quenching effect is entirely caused by a failure to correct for the inner-filter effect.
使用荧光猝灭技术和等温热力学滴定法（ITC）研究了核苷逆转录酶抑制剂司他夫定与人血清白蛋白（HSA）之间的相互作用。在司他夫定存在的情况下，白蛋白荧光猝灭呈现出良好的线性关系。通过分析这些数据，我们得到了解离常数 K(d)=(18.18 ± 0.46) × 10(-5)M。然而，由于 ITC 实验得出的结果相互矛盾，我们检查了荧光猝灭数据是否存在内滤效应，这是观察到的猝灭的主要混杂因素。基于紫外-可见吸收数据，我们对观察到的荧光强度进行了校正，并根据 ITC 结果得出结论，即司他夫定与 HSA 的结合可以忽略不计，观察到的猝灭效应完全是由于未能校正内滤效应所致。
