基于金纳米颗粒等离子体共振吸收的典型四环素类药物分析方法

Determination of typical tetracyclines based on the plasmon resonance absorption of gold nanoparticles

研究发现,在pH9.37的BR缓冲体系中,典型四环素类药物盐酸土霉素、盐酸多西环素、盐酸四环素、盐酸金霉素与氯金酸发生氧化还原反应生成的金纳米颗粒在500～550nm波长范围内显示出特征的等离子体共振吸收,且吸光度值与四环素类药物的浓度在一定范围内呈良好的线性关系,据此建立了测定四环素类药物的等离子体共振吸收分析新方法.该方法能分别检测0.5～20,0.5～16,0.5～16,0.5～20μmol/L范围的盐酸土霉素、盐酸多西环素、盐酸四环素和盐酸金霉素,对应的检出限分别为0.20,0.16,0.15,0.18μmol/L.对浓度为20.0μmol/L的盐酸土霉素进行了15次平行测定,其相对标准偏差为1.53%.该方法成功用于合成样和片剂中土霉素的测定,且根据溶液颜色变化实现了上述四环素类药物的三原色可视化定量检测.

The typical tetracyclines,such as oxytetracycline,doxycycline,tetracycline and chlortetracycline,could react with chloroauric acid to form gold nanoparticles in an aqueous solution（pH 9.37） .The prepared gold nanoparticles had characteristic plasmon resonance absorption bands at 500-550 nm,and the intensities of these bands changed in proportion with the concentrations of the tracyclines.This was used to develop a new assay for quantitative detection of tetracyclines.Under the optimum conditions,the linear ranges of the calibration curves of oxytetracycline,doxycycline,tetracycline and chlortetracycline were 0.5-20,0.5-16,0.5-16 and 0.5-20μmol/L,respectively.The limits of detection（3σ） for oxytetracycline,doxycycline,tetracycline,and chlortetracycline were 0.20,0.16,0.15 and 0.18μmol/L,respectively.The relative standard deviation was 1.53%（cOTC=20.0μmol/L,n=15） .This method was successfully applied to the analysis of composite samples and oxytetracycline tablets.Visual quantitative detection of tetracyclines based on three primary colours had been made according to the change of the solution’s color.