基于CdTe量子点测定烟酸诺氟沙星的新方法研究

New Method for Detection of Norfloxacin Nicotinate Based on the CdTe Quantum Dots

以巯基乙酸修饰的CdTe量子点(QDs)为荧光探针,考察了不同条件下烟酸诺氟沙星对CdTe QDs荧光的猝灭作用.发现在磷酸缓冲液中(PBS,pH 7.40,0.10 mol/L),其猝灭作用最强,随后对其猝灭机理进行了讨论.在此基础上建立了基于荧光猝灭法检测烟酸诺氟沙星含量的新方法,该方法的线性范围为0.10～90μg/mL,线性方程为ΔF=26.6206c-20.8273(μg/mL),相关系数r为0.997,检测限(3S/N)为2.50×10-2μg/mL.应用此法检测兽药雏乐宝、烟酸氟哌酸和强效氟哌酸中烟酸诺氟沙星的含量,百分标示量在93.0%～104.0%范围内变化,相对标准偏差(RSD)≤4.2%;与常用的紫外分光光度法相比,该法具有准确度高、灵敏度高且检测范围宽等优势,显示出潜在的应用前景.

The fluorescence quenching of norfloxacin nicotinate to thioglycolic acid stabilized CdTe quan-tum dots（QDs） has been systematically investigated by using CdTe QDs as a fluorescence probe.On the ba-sis of that,a sensitive method for the determination of norfloxacin nicotinate was developed.The linear equation was ？F=26.6206c-20.8273（μg/mL） and its linear range was 0.10～90 μg/mL with correlation coefficient of 0.997.The limit of detection was 2.50×10-2 μg/mL.Then the proposed new method was ap-plied to measure the quantity of real sample（such as norfloxacin nicotinate solid powder）,compared with the labeled amount,the accuracy was within 93.0%～104.0% and the RSD value for every sample five times determinations was or lower than 4.2%.This new method shows a bright application prospect for detection of norfloxacin nicotinate due to its several advantages such as accurate,high sensitivity,and wide detection range while compared with traditional ultraviolet spectrophotometry.