title: Investigation of competitive binding of ibuprofen and salicylic acid with serum albumin by affinity capillary electrophoresis.
abstract: Ibuprofen and salicylic acid, two typical non-steroidal anti-inflammatory drugs, are used commonly as analgesic drug in clinical medicine and sometimes are co-administered. When the drugs are co-administered, the drug-drug interactions may occur, and can lead to alter the safety and efficacy of drugs, resulting in variations in drug response of the co-administered drugs. Affinity capillary electrophoresis (ACE) was employed to investigate the competitive binding of ibuprofen and salicylic acid on serum albumin. Mobility ratio, derivatives from mobility shift method, was used to deduce the binding constant (K(b)). The binding constants of ibuprofen with HSA are 2.97×10⁶ M⁻¹ and 7.07×10⁴ M⁻¹, respectively; while for salicylic acid, the binding constant is 5.99×10⁴ M⁻¹. The competitive binding of the two drugs was investigated by addition of excessive ibuprofen into the solutions containing constant concentrations of salicylic acid and serum albumin. The results confirmed that ibuprofen and salicylic acid have different high-affinity binding site, but share some low-affinity binding sites on the serum albumin; and ibuprofen is able to partially replace salicylic acid from the preformed binary complexes of serum albumin and salicylic acid.
authors.affiliation: College of Chemistry and Chemical Engineering, Central South University, Changsha, Hunan 410083, PR China.
authors.forename: Zhu-Mei
authors.initials: ZM
authors.lastname: Li
authors.forename: Chuan-Wan
authors.initials: CW
authors.lastname: Wei
authors.forename: Yintang
authors.initials: Y
authors.lastname: Zhang
authors.forename: Di-Shan
authors.initials: DS
authors.lastname: Wang
authors.forename: You-Nian
authors.initials: YN
authors.lastname: Liu
mesh_terms: D000818:Animals; D001667:Binding, Competitive; D002417:Cattle; D019075:Electrophoresis, Capillary / Q000379:methods*; D007052:Ibuprofen / Q000737:chemistry / Q000378:metabolism*; D016014:Linear Models; D011485:Protein Binding; D020156:Salicylic Acid / Q000737:chemistry / Q000378:metabolism*; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism*
chemical_list: D012710:Serum Albumin, Bovine; D020156:Salicylic Acid; D007052:Ibuprofen