563MERCAPTOACETIC ACID CAPPED CDSE QUANTUM DOTS AS FLUORESCENCE PROBE FOR SIMPLE DETERMINATION OF Pb2+ IN AQUEOUS SOLUTIONS BY LUMINESCENT MEASUREMENTSA new chemiluminescence (CL) method using water-soluble mercaptoacetic acid (MAA) capped CdSe quantum dots (QDs) as sensitizers is proposed for the determination of Pb2+. MAA-CdSe QDs were synthesized by using MAA as stabilizerin aqueous solutions. The stability of QDs were studied. The shape, size and spectral properties Of MAA-capped-CdSe QDs were characterized by Ultra Violet-Visible absorption Spectroscopy, transmission electron microscopy (TEM) and spectrofluorometry. A pH 6 was selected for measurement. Also the influence of the foreign cations, drugs and amino acids on the fluorescence intensity of MAA-CdSe QDs was studied and Results showed a high selectivity of the MAA-CdSe QDs towards pb2+ ions. There is a good linear relationship between the relative chemiluminescence intensity and the concentration of pb2+ in the range of 1.6×10-9-1.3×10-8M of pb2+ ions with a correlation coefficient (R2) of 0.9967. The limit of detection of this system was found to be 1.1×10−9 M. This method is simple, sensitive and lowcost.Samadi76@yahoo.comResearch732017Mercaptoacetic acid,CdSe quantum dots,ChemiluminescenceSamadi N,Saadatmand S,Narimani SDepartment of Chemistry, Faculty of Science, Urmia University, Urmia, Iran.,Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran.,Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran.