Fluorescence quenching of CdSe quantum dots by nitroaromatic explosives and their relative compounds

CdSe quantum dots (QDs) were synthesized in oleic acid and octadecene medium under high-temperature and dispersed in chloroform. Nitroaromatic explosives and their relative compounds, 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), nitrobenzene (NB), 2,4-dinitrochlorobenzene (DNBCl) and p-nitrotoluene (NT) can obviously cause the fluorescence quenching of the synthesized QDs. Under the optimum conditions, a nonlinear response was observed over the concentration range of 10(-8) to 10(-5) M for them all. The modified Stern-Volmer quenching equations of In I-0/I versus C show a good linear relation in 10(-5) M order of magnitude, and the detection limits approach 10(-6) to 10(-7) M. (C) 2007 Published by Elsevier B.V.