基于甲基红-CdTe量子点荧光共振能量转移体系测定痕量强力霉素

Fluorescence Resonance Energy Transfer between Methyl Red and CdTe Quantum Dots and Its Application to the Determination of Trace Doxycycline

本文以甲基红（MR）为能量给体,CdTe量子点（QDs）为能量受体,构建了MRCdTe QDs荧光共振能量转移体系,同时基于荧光猝灭法建立了检测痕量强力霉素（DOX）的新方法。实验表明,在pH=8.0的Tris-HCl缓冲介质中,聚乙烯醇（PVA）胶束能缩短MR与CdTe QDs分子间的距离,二者之间发生有效能量转移,使CdTe QDs荧光强度增强。而强力霉素能够猝灭该体系中CdTe QDs的荧光强度,以此建立了能量转移荧光猝灭法测定痕量强力霉素的新方法。实验表明强力霉素的线性范围为8~350×10-9 mol/L,检出限为2.1×10-9 mol/L。方法可应用于实际样品中强力霉素残留的测定。

Fluorescence resonance energy transfer（FRET） from methyl red（MR） to CdTe QDs and the application for determining trace doxycycline were studied. It was found that in the presence of PVA,the effective energy transfer could occur between methyl red and CdTe QI）s in the Tris-HCl buffer solution at pH = 8. 0 and the fluorescence intensity of CdTe QDs increased. As adding doxycycline, the fluorescence intensity of FRET system decreased. There was a good linear relationslip between the concentration of doxycycline and the fluorescence quenched intensity. The linear range was 8-350 × 10-9 mol/L,and a detection limit was 2.1 × 10-9 mol/L. Then, a new determination strategy of doxycycline was built. The method was applied to the determination of doxycycline in real samples.