Department of Chemistry, Lanzhou University, Lanzhou 730000, People's Republic of China.
Talanta. 2002 Jun 10;57(4):693-700. doi: 10.1016/s0039-9140(02)00075-9.
A simple, sensitive and selective method has been developed for the determination of protein using resonance light scattering (RLS) technique. The method is based on the interaction of protein and arsenazo-DBC-Al(3+) in the pH range of 5.0-7.0, which causes a substantial enhancement of the resonance scattering signal of arsenazo-DBC-Al(3+) in the wavelength range of 300-550 nm with the maximum RLS platform at 405-420 nm. With this method, 2.50-50.00 mug ml(-1) of bovine serum albumin (BSA) and 2.50-60.00 mug ml(-1) of human serum albumin (HSA) can be determined, and the detection limits, calculated three times the standard deviation (S.D.) of six blank measurements, for BSA and HSA were 123.4 and 89.6 ng ml(-1), respectively. Moreover, the method is free from interference from many amino acids and metal ions. The method, with high sensitivity, selectivity and reproducibility, was satisfactorily applied to the determination of total protein in human serum samples. Mechanism studies indicated that arsenazo-DBC-Al(3+) could bind to BSA depending mainly on electrostatic forces, which results in enhanced RLS in the arsenazo-DBC-Al(3+)-protein system.
已开发出一种简单、灵敏和选择性的方法，用于使用共振光散射 (RLS) 技术测定蛋白质。该方法基于蛋白质与偶氮胂-DBC-Al(3+) 在 pH 值为 5.0-7.0 的范围内相互作用，这导致偶氮胂-DBC-Al(3+)在 300-550nm 波长范围内的共振散射信号显著增强，最大 RLS 平台位于 405-420nm。使用该方法，可以测定 2.50-50.00 μg ml(-1)的牛血清白蛋白 (BSA) 和 2.50-60.00 μg ml(-1)的人血清白蛋白 (HSA)，并且 BSA 和 HSA 的检测限，通过六个空白测量的标准偏差 (S.D.) 的三倍计算，分别为 123.4 和 89.6ng ml(-1)。此外，该方法不受许多氨基酸和金属离子的干扰。该方法具有高灵敏度、选择性和重现性，可满意地应用于人血清样品中总蛋白的测定。机制研究表明，偶氮胂-DBC-Al(3+)主要通过静电力与 BSA 结合，导致偶氮胂-DBC-Al(3+)-蛋白质体系中 RLS 增强。
