A light scattering and fluorescence emission coupled ratiometry using the interaction of functional CdS quantum dots with aminoglycoside antibiotics as a model system

作者：Qie Gen Liao; Yuan Fang Li; Cheng Zhi Huang^*

来源：Talanta, 2007, 71(2): 567-572.

DOI：10.1016/j.talanta.2006.04.035

• light scattering and fluorescence emission coupled ratiometry
• CdS quantum dots (CdS-QDs)
• aminoglycoside antibiotics

Any signals, if their intensities have simple functional relationship with analyte concentration, can be applied to analytical purposes. Rayleigh light scattering signals and fluorescence signals are twins in flurospectroscopy, so the light scattering signals are the major interference when the Stokes shift is small. Herein, we propose a light scattering and fluorescence emission (LS-FL) coupled ratiometry using US quantum dots (QDs) as a fluorescence probe to detect aminoglycoside antibiotics (AGs). As model analytes, AGs, when attached to the surface of CdS-QDs via electrostatic interaction in aqueous medium, result in strong enhanced light scattering (LS) emission characterized at 376 nm and fluorescence quenching of CdS-QDs at 500 nm. Thus, a ratiometry using the coexistent light scattering and fluorescent emission signals has been proposed. Based on the linear relationship between logarithm of light scattering and fluorescence emission ratio (R) and logarithm of AGs concentration, a novel assay of AGs is established with the limits of detection (3 sigma) being 58-190 nmol l(-1), and applied successfully to detect AGs injection and serum samples.

• 出版日期2007-2-15
• 单位西南大学