Department of Pharmaceutical Sciences, University of Bologna, Via Belmeloro 6, 40126 Bologna, Italy.
J Pharm Biomed Anal. 2010 Oct 10;53(2):179-85. doi: 10.1016/j.jpba.2010.03.005. Epub 2010 Mar 7.
A series of synthesised tocainide analogues were characterized for their human serum albumin (HSA) binding, using high-performance liquid affinity chromatography (HPLAC) and circular dichroism (CD). The synthesis and physico-chemical characterization of compounds 7a-7d is reported here. For the HPLAC investigation HSA was covalently immobilized to the silica matrix of the HPLC column, using an anchoring procedure, which allows the binding properties of the protein to be maintained. The HSA-based column was used for getting information on the high affinity binding sites of the tocainide analogues to HSA. According to the displacement chromatography approach, the retentions of the analytes were determined in the absence and in the presence of increasing concentrations of competitors known to bind to specific binding sites on the protein. The same system, drug/protein, was investigated in solution by CD. The analysed compounds, proved active as sodium channel blockers, showed a much higher affinity to the serum carrier with respect to the parent compound, tocainide. Further, a non-cooperative interaction at sites I and II, and an almost independent binding at the bilirubin binding site on HSA were hypothesised on the bases of the competition experiments.
一系列合成的托卡尼定类似物被表征为其与人血清白蛋白（HSA）的结合，使用高效液相亲和色谱（HPLAC）和圆二色性（CD）。本文报道了化合物 7a-7d 的合成和物理化学性质。为了进行 HPLAC 研究，使用锚定程序将 HSA 共价固定在 HPLC 柱的硅胶基质上，该程序允许保持蛋白质的结合特性。基于 HSA 的柱用于获取有关托卡尼定类似物与 HSA 高亲和力结合位点的信息。根据置换色谱法，在不存在和存在已知与蛋白质上的特定结合位点结合的竞争物的情况下，确定了分析物的保留时间。以同样的方式，通过 CD 在溶液中研究了药物/蛋白质系统。所分析的化合物被证明是有效的钠离子通道阻滞剂，与母体化合物托卡尼定相比，对血清载体具有更高的亲和力。此外，根据竞争实验，假设在部位 I 和 II 处存在非协同相互作用，并且在 HSA 的胆红素结合部位处存在几乎独立的结合。
