Interaction of antithyroid drugs with bovine serum albumin: Electrophoretic and fluorimetric study

摘要: Abstract The pre‐equilibrium capillary zone electrophoretic (pre‐eq CZE) method to determine association constants of active anionic forms antithyroid drugs: 6‐ n ‐propyl‐2‐thiouracil (PTU), 6‐methyl‐2‐thiouracil (MTU), 2‐thiouracil (TU) with bovine serum albumin (BSA) under physiological pH 7.4 has been developed for the first time. Using decrease selective electrochromatographic peak area a drug form due binding BSA K binary complexes were calculated. It found that (log  ) TU, MTU, and PTU are equal 2.99, 1.85, 2.11, respectively. interaction PTU, 2‐mercapto‐1‐methylimidazole (MMI), ethyl‐3‐methyl‐2‐thionoimidazoline‐1‐carboxylate (Carb), which is considered be prodrug MMI, investigated conditions by means fluorescence spectroscopy. Fluorescence emission spectra in presence thioamides recorded at 295 nm excitation wavelength clearly show studied drugs act as quenchers, except acts quencher when being excited 280 nm. light excites tryptophan residues, while 280 nm both tyrosine residues. Carb have 4.51, 4.30, 2.64, 4.32, © 2009 Wiley‐Liss, Inc. American Pharmacists Association J Pharm Sci 99: 1567–1573, 2010