Synthesis of Zn(II)-Cloxacillin Sodium Complex and Study of Its Interaction with Calf Thymus DNA

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Jian-Bin Chao¹, Meng-Dan Xu¹, Cai-Xia Yin², and ShuPing Huang^1*

¹The Institute of Modern Chemistry, Shanxi University, Shanxi, P. R. China 030006; E-mail: chao@sxu.edu.cn

²Institute of Molecular Science, Key Laboratory of Chemical Biology and Molecular Engineering of the Ministry of Education, Shanxi University, Taiyuan 030006, China

^* To whom correspondence should be addressed.

Received July 3, 2006; Revision received September 20, 2006

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In this paper, a solid complex of cloxacillin sodium (CS) with Zn(II) was prepared by coprecipitation and characterized by UV, fluorescence, IR, and thermal spectra. Furthermore, the nature of the complex has been studied by ¹H-NMR and ¹³C-NMR spectroscopy. The influence of Zn(II) on the combination of CS and calf thymus DNA (CT DNA) was studied using fluorescence spectrophotometry, and the formation of binary CS-Zn(II) and CS-CT DNA complexes and ternary CS-Zn(II)-CT DNA complex was studied. The results show that the fluorescence intensity of CS can be quenched in the presence of Zn(II) or DNA. In the presence of Zn(II), the fluorescence quenching action of DNA on CS was strongly enhanced. Based on the fluorescence intensity, the formation constants of CS-Zn(II) and CS-CT DNA complexes were calculated, and the mechanism of interaction between CS, Zn(II), and DNA is discussed.

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KEY WORDS: cloxacillin sodium, Zn(II), DNA, complexes, NMR, fluorescence

DOI: 10.1134/S0006297907020046

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