Capillary Electrophoresis Non-steroidal Drugs And Protein And Peptide Interactions

The interactions of small molecular and biological macromolecular have been the central in chemical and biological research. The investigation of interaction between serum albumin and drug is currently wider aspect. Serum albumin is the abundance carrier protein, which can maintain colloid osmotic pressure. Due to many binding sites, serum albumin could carry various endogenous and exogenous substances. The efficacy of drugs would be affected through the process of bind-release during the interaction of drug and serum albumin. Therefore, the study of interaction not only clears coordination, but also provides favorable information for drug efficacy. That becomes the essential part in pharmacokinetics and biomedicine fields.With the advantages of simple equipment, short analysis time, high efficiency and small amount of sample, CE has become the beneficial tool for investigation of molecular interaction.In our work, CE was used to study the interaction of drug and protein so as to obtain the details of the interaction. In this paper, the competitive binding of non-steroidal to protein was studied based on the principle of interaction. Details are as follows:(1) Affinity interactions of ibuprofen and salicylic acid with serum albumin were investigated according to the change of mobility. The binding constants were obtained:3.92×104 M-1 for Sal with BSA; 5.99×104 M-1 for Sal with HSA;1.27×106M-1,8.02×104 M-1 for Ibu with BSA; 2.97×106 M-1,7.07×104 M-1 for Ibu with HSA.(2) CE was applied in the competitive binding between two drug ligands and one protein acceptor based on competitive principle. We studied the competition of Ibu and Sal, when they simultaneously bound to protein. The competent mobility of the system changed when Ibu injected into the buffer solution with constant Sal and protein. The results revealed that Ibu could displace Sal partially from complex Sal-SA.(3) The interaction of Ibu and oligopeptide of amyloid peptide was studied by CE. The binding constant was 1.42×104 M-1. Further, fluorescence was used for the interaction, and the constant was 3.6×103 M-1, which is consistent with that of CE.(4) Fluorescence spectral was used to investigate the interaction of Aβ1-16 and HSA. Also the binding constant was gained 2.95×105 M-1 through the change of fluorescence intensity.