Miller Iu I, Dobretsov G E, Kolchin Iu A
Biofizika. 1991 May-Jun;36(3):505-8.
Fluorescent probe N-phenyl-1-amino-8-sulfonaphthalene (ANS) was used for studying pH-dependent structural N-F-transition in human serum albumin of two kinds: in commercial albumin and in natural blood serum. The kinetics of ANS fluorescence decay in albumin solutions was measured. There were found two types of the sites occupied by ANS in albumin under physiological conditions (pH 7.4). In the first binding site ANS fluorescence decay time was 16.6 +/- 0.3 nsec and it was not significantly changed at N-F transition (pH 4.0). In the second binding site the decay time was dependent on pH in commercial albumin and was not significantly changed in serum. In the second binding site there were individual differences of ANS decay time (4.3 +/- 0.6 nsec). The observed ANS fluorescence intensity enhancing (about 40-50%) in N-F transition may be explained by an increase of albumin binding sites capacity for ANS.
荧光探针N-苯基-1-氨基-8-磺酸萘（ANS）用于研究两种人血清白蛋白中pH依赖性结构N-F转变：市售白蛋白和天然血清中的白蛋白。测量了白蛋白溶液中ANS荧光衰减的动力学。发现在生理条件（pH 7.4）下白蛋白中被ANS占据的位点有两种类型。在第一个结合位点，ANS荧光衰减时间为16.6±0.3纳秒，在N-F转变（pH 4.0）时没有显著变化。在第二个结合位点，市售白蛋白中的衰减时间取决于pH，而在血清中没有显著变化。在第二个结合位点，ANS衰减时间存在个体差异（4.3±0.6纳秒）。在N-F转变中观察到的ANS荧光强度增强（约40-50%）可以通过白蛋白对ANS结合位点容量的增加来解释。
