Interaction and fluorescence quenching study of levofloxacin with divalent toxic metal ions

Eurasian Journal of Analytical Chemistry

Khwaja S. Siddiqi¹  Shaista Bano¹  Aftab Aslam Parwaz Khan¹  Ayaz Mohd¹ 

关键词: Ranitidine hydrochloride;    Sodium periodate;    Crystal violet;   

DOI  :  10.12973/ejac.2010.00095a

学科分类：分析化学

来源: Eurasian Journal of Analytical Chemistry

【 摘 要 】

The binding interaction of levofloxacin (LF) with toxic metal ions Cd⁺², Hg⁺² and Pb⁺²was investigated in aqueous acidic medium by absorption and fluorescence spectrophotometry. The experimental results showed that the metal ions quench the fluorescence intensity of LF by forming LF₂ -metal complex. It was found that static quenching was the main reason of fluorescence quenching. Quenching of Lf by toxic metal follows the order Hg>Cd>Pb. The stoichiometry and logK of formed chelate was determined by absorption and fluorescence spectrophotometry. The quenching constant Ksv and the binding sites “n” were determined together with their thermodynamic parameters at 25 ºC and 35 ºC. The positive entropy change indicated the gain in configurational entropy as a result of chelation. The process of interaction was spontaneous and mainly ∆S-driven.  

【 授权许可】

Unknown