硫化镉量子点-硫酸依替米星体系的共振瑞利散射和共振非线性散射光谱研究及其分析应用

在弱酸介质中,硫化镉量子点(CdS-QDs)与硫酸依替米星(ETM)在静电引力和疏水作用力下,形成粒径更大的聚集体,导致共振瑞利散射(RRS)、二级散射(SOS)和倍频散射(FDS)显著增强,其最大散射峰分别位于310 nm(RRS),568 nm(SOS),320 nm(FDS).在一定范围内ETM浓度与三种散射增强程度(△I)成正比,可用于ETM的测定,其中RRS的灵敏度最高,其检出限(3σ)为1.6 ng/mL.考察了共存离子的影响,表明方法有良好的选择性.据此发展了以CdS-QDs作探针,高灵敏、简便测定ETM的共振瑞利散射新方法,用于人血清和尿样中ETM的测定,平均回收率在94.5%～113.7%之间.

Abstract：

In a medium of pH = 5.6, CdS quantum dots could react with etimicin sulfate to form larger aggregates by virtue of electrostatic attraction and the hydrophobic force, which resulted in a great enhancement in resonance Rayleigh scattering (RRS) and resonance non-linear scattering such as second-order scattering (SOS) and frequency doubling scattering (FDS). The maximum scattering peaks were located at 310 nm for RRS, 568 nm for SOS and 320 nm for FDS. The enhancements of scattering intensity (△I) were directly proportional to the concentration of etimicin sulfate (ETM) within a certain range. Of the three methods, RRS had the highest sensitivity, its detection limit (3σ) being 1.6 ng/mL. An examination of the effects of coexisting substances showed that the method had good selectivity. Based on these results, a new method, highly sensitive and simple, was developed, which can be used to determinate ETM by CdS-QDs as a probe. The recovery for the determination of ETM in human serum and uric samples was in the range of 94. 5%-113.7%.