A Ratiometric Fluorescence Sensing for Carboxylesterase Based on Semiconducting Polymer Quantum Dots
10.11895/j.issn.0253-3820.171320
- VernacularTitle:基于半导体聚合物量子点的羧酸酯酶比率荧光传感
- Author:
Ting Ting CAO
1
;
Yong Jun SUN
;
Feng GAO
Author Information
1. 安徽师范大学化学与材料科学学院
- Keywords:
Semiconducting polymer dots;
Ratiometric fluorescent sensor;
Carboxylesterase
- From:
Chinese Journal of Analytical Chemistry
2017;45(12):1930-1936
- CountryChina
- Language:Chinese
-
Abstract:
A carboxylesterase ( CaE ) ratiometric fluorescent probe based on semiconducting Poly ( 9 , 9-dioctylfluorenyl-2,7-diyl) (PFO) polymer quantum dots (Pdots) was prepared. The negatively charged PFO Pdots and the positively charged polyethyleneimine ( PEI) formed a nanocomposite Pdots@PEI by electrostatic interaction, and emitted fluorescence at 440 nm and 467 nm. In the presence of CaE, the substrate fluorescein diacetate ( FDA ) was hydrolyed into negatively charged fluorescein molecule, and could get closer to the positively charged Pdots@PEI due to electrostatic interactions, which could induce resonance energy transfer, resulting in the energy donor Pdots@ PEI fluorescence intensity gradually weakened and the fluorescence intensity of the FDA hydrolysis product increased. Based on the fluorescence intensity ratio of Pdots@PEI and the fluorescence enhancement of FDA hydrolysis products, a new method for selective detection of CaE was established. Under the optimal conditions, the linear range of the method on CaE testing was 0. 75-50 U/L with detection limits of 0 . 75 U/L ( S/N=3 ) . This method was used for the detection of the content of CaE in rabbit blood with satisfactory results.
