【摘要】 在pH 7.60 NH3·H2O-NH4Cl缓冲溶液中,阳离子表面活性剂十六烷基三甲基溴化胺(Cetyltrime-thylammonium Bromide,CTMAB)存在下,利用Pb2+与2,3,7-三羟基-9-(2,4-羟基)苯基荧光酮(2,3,7-trihy-droxy-9-(2,4-dihydroxy)phenyl fluorone,DHPF)配位产生荧光猝灭效应,建立了荧光猝灭法测定微量Pb2+的新方法.实验结果表明,Pb2+与DHPF形成1∶2配位化合物,Pb2+含量在0~1.60μg/5mL范围内与ΔF成线性关系,回归方程为ΔF=294.841 7×C+4.715 6(C:μg/5mL),相关系数r=0.999 1,方法用于狗牙根中Pb2+含量测定,结果满意.更多还原

【Abstract】 A new method for determining the content of trace Pb2+is established using fluorescence quenching effect,which is from the reaction of Pb2+and 2,3,7-trihy-droxy-9-(2,4-dihydroxy)phenyl fluorone(DHPF)in pH 7.60NH3·H2O-NH4 Cl buffer solution with the existence of cationic surfactant cetyl trimethyl ammonium bromide(CTMAB).The experimental results show that the molar ratio of Pb2+to DHPF is 1∶2,Pb2+andΔF have a linear relationship when the content of Pb2+is in the range of 0-1.60μg/5mL.The regression equation isΔF=294.8417×C+4.7156(C:μg/5 mL)and the correlation coefficient is 0.9991.With this method,satisfying results are gained in the determination of content of Pb2+in Cynodon dactylon.更多还原