Rapid development of nanomaterials has extended a new horizon for sensitive and easy-to-use sensors. Robust determination of nitro-explosives with nano-sensors has attracted great attentions due to the increasing safety concern. In this work, strongly fluorescent polyacrylamide coated CdTe(S) quantum dots (CdTe(S)@PAM QDs) with good dispersity and stability have been prepared by a facile, effective and reliable photochemical method through simple one-step UV irradiation. The prepared QDs were systematically characterized and the results proved that the prepared material could be readily used for the sensitive and selective sensing of 2,4,6-trinitrotoluene (TNT). The influence of experimental conditions on the analytical performance was investigated. With a QD concentration of 3.13μmol/L, the calibration curve of TNT was linear up to 0.48μmol/L, and a LOD (S/N=3) of 2.1nmol/L was attained. In combination of simple analyte extraction, no interference was observed from common inorganic ions and organic substances. TNT in samples with complicated matrices was successfully determined. The standard addition recoveries obtained from water and soil samples were in a range of 93.2–106.3%.
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