Interaction of cefotaxime with human serum albumin:Investigation by fluorescence spectroscopy

The binding characteristics of cefotaxime(CTX),Cu(Ⅱ)and BSA have been studied by fluorescence spectroscopy in physiological pH conditions.The results showed that both Cu(Ⅱ) and CTX could quench the fluorescence intensity of BSA via a nonradiative energy transfer mechanism.Moreover,CTX could quench the fluorescence of BSA significantly in the presence of Cu(Ⅱ).The binding constants(K) and the binding sites(n) were calculated after analyzing fluorescence quenching data with double-reciprocal equation.The K and n between CTX and BSA were 3.11×104L/mol and 1.03,respectively in the CTX-BSA complex,while the K and n between Cu(Ⅱ) and BSA were 1.13×103 L/mol and 0.74 respectively in the binary complex of Cu(Ⅱ) and BSA.