Near infrared-response ratiometric fluorescence sensor for the sensitive detection of Cu2+

Abstract

Abstract The design of novel Cu2+ quantitative sensors with highly sensitivity and selectivity is a hot topic of modern chemistry. Herein, a novel ratiometric fluorescence (PL) sensor based on the red-emitting CdTeS quantum dots (QDs) and blue-emitting polyethyleneimine-functionalized carbon dots (PEI-CDs) was firstly designed for sensing Cu2+. In the presence of Cu2+, a good linear relationship between the ratios (F520/F690) of the two peak intensities and the concentrations of Cu2+ was observed in the range of 0.01-250\xa0µM with the correlation coefficient (R2) of 0.993 and the detection limit as low as 8.07\xa0nM. The ratiometric nanosensor was also used to successfully determine Cu2+ in plasma samples with satisfactory results obtained. Therefore, we hold the opinion that the developed ratiometric fluorescent sensor based on CdTeS QDs/PEI-CDs will provide technical support for the point-of-caretesting of Cu2+.