摘要
在pH 7.40和离子强度0.15 mol/L的模拟生理条件下,托拉塞米(TOR)对牛血清白蛋白(BSA)的内源荧光产生较强的猝灭作用.从吸收光谱的变化、温度对猝灭作用的影响及猝灭常数判断该猝灭作用是TOR与BSA形成基态配合物而导致的静态猝灭过程.文中计算了TOR与BSA的结合常数K、结合位点数n和相关的热力学函数.在最大猝灭波长342 nm处,荧光猝灭程度(?F)与托拉塞米的浓度成正比,线性范围和检出限分别为0.02～5.0μg/mL和6.3 ng/mL.本文还研究了适宜的反应条件,考察了共存物质的影响,表明方法具有较好的选择性,据此提出了以BSA为探针快速测定痕量TOR的荧光光谱新方法,适用于服用TOR后尿样和片剂中托拉塞米的测定.
Under the simulated physiological conditions（at pH 7.40 and ionic strength=0.15 mol/L）,the intrinsic fluorescence of bovine serum albumin（BSA） was quenched by torasemide（TOR）.From the change of absorption spectrum,the effect of temperature and the quenching constant,this procedure was judged to be static quenching process on account of the TOR interacting with BSA to form ground state coordination compounds.In this paper,the binding constants（K）,the binding sites（n） and the thermodynamic properties between TOR and BSA had been calculated.The results show that the TOR can quench the fluorescence of BSA and the mechanism is static quenching process.The fluorescence of BSA was quenched regularly by the TOR in certain ranges.And at the maximum quenching wavelength 342 nm,the value of the fluores-cence quenching（.F） was directly proportional to the concentration of TOR in the range of 0.02～5.0 μg/mL with the detection limit being 6.3 ng/mL.In the work,the optimum conditions and the influencing factors were investigated.The results showed that this method exhibited a high sensitivity and selectivity.Based on this,a novel fluorescence quenching method for the determination of trace TOR with BSA as a fluorescence probe has been developed.It has been applied to the determination of TOR urine samples after the patient having TOR and in tablets with satisfactory results.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2011年第12期1408-1414,共7页
Acta Chimica Sinica
基金
国家自然科学基金(No.20872078)
发光与实时分析重庆市重点实验室(No.CSTC
2006CA8006)
西南大学大型仪器设备开放基金(No.201005)资助项目
关键词
托拉塞米
牛血清白蛋白
荧光光谱法
torasemide
bovine serum albumin
fluorescence spectroscopy
