CdTe量子点-罗丹明B荧光共振能量转移猝灭法测定金银花中的微量铜

摘要

研究CdTe量子点(供体)和罗丹明B(受体)之间荧光共振能量转移的最佳条件,建立了荧光共振能量转移猝灭法测定金银花中微量铜的新方法.采用十六烷基三甲基溴化铵,在pH 6.00的Tris-HCl缓冲液中,Cu2+能对能量转移体系中罗丹明B荧光峰强猝灭从而测定铜的含量.Cu2+浓度在1.3×10-4～3.1×10-2 μg·mL-1范围内与罗丹明B的荧光强度变化ΔF呈现良好线性关系(r=0.996),检测限为4.6×10-5μg·mL-1,RSD为3.5%,平均回收率为103.4%(n=5).该方法适用于金银花中微量铜的测定.%The present work is to find the optimum condition for fluorescence resonance energy transfer between CdTe QDs (donor) and rhodamine B (acceptor) and form a new method to detect copper in Flos Lonicerae Japonicae. In tris-HCl buffer solution at pH 6. 00, by employing cetyltrimethylammonium bromide, Cu2+ can quench the fluorescence intensity of BRB and detect the concentration of Cu2+. Results show that a linear relationship could be established between the quenched fluorescence intensity of RhB and the cOncentration of Cu2+ in the range of 1.3 × 10-4 ～3. 1 × 10-2μg · mL-1 , the limit of detection was 4. 6×10-s tag · mL-t (r=0. 996), RSD and the average recovery was 3. 5％ and 103.4％ (n= 5), respectively. It is concluded that the developed method was proved to be feasible to detect copper in Flos Lonicerae Japonicae.