基于藏红T的荧光熄灭荧光光度法测定水样中痕量铬(Ⅵ)  

Fluorophotometric Determination of Trace Amounts of Chromium(Ⅵ) in Water Samples Based on the Fluorescence Quenching of Safranine T

作　　者：宋仲容[1] 何家洪[1,2] 高志强[1] 徐强[1] 

机构地区：[1]重庆文理学院化学与环境科学系,永川402168 [2]重庆大学化学化工学院,重庆400044

出　　处：《理化检验（化学分册）》2009年第10期1222-1224,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：重庆市教育委员会资助项目(KJ051201)

摘　　要：研究了盐酸介质中,铬(Ⅵ)氧化藏红T荧光猝灭的试验条件,提出了荧光熄灭荧光光度法测定痕量铬(Ⅵ)的方法。在酸性条件下,藏红T的最大激发波长为559.0 nm,最大发射波长为575.0 nm。铬(Ⅵ)的质量浓度在128μg·L^(-1)以内与体系荧光强度呈线性关系,检出限(3S/N)为2.5μg·L^(-1)。方法用于电镀废水、工业废水、自来水和湖水中痕量铬(Ⅵ)的测定,并与二苯碳酰二肼光度法进行对照,结果相符,加标回收率在98.2%～105.0%范围,相对标准偏差小于3%。Quenching of fluorescence of safranine T by oxidation reaction with Cr（Ⅵ） in an acidic medium of 0. 12 mol · L^-1 HCl was observed. Linear relationship between values of decrease in fluorescence intensity （△F= F0-F） and concentration of Cr（ Ⅵ ） was obtained in the range within 128μg· L^-1, when measured at wavelengths of 559. 0 nm （λex） and 575. 0 nm （λem）. Detection limit （3S/N） found was 2. 5μg·L^-1. Based on these facts, a fluorophotometric method for determination of traces of Cr（ Ⅵ） in water samples （i. e. electroplating waste water, industrial waste water, tap water and lake water） was proposed. In its application to the analysis of several water samples, the results obtained were in consistency with the results obtained by the diphenylcarbazide-photometrie method. Values of recovery found by standard addition method were ranged from 98.2% to 105. 0%, and values of RSD＇s （n=6） were in the range of 1.7% to 2.7%.

关 键 词：荧光光度法 荧光熄灭 藏红T 痕量铬(Ⅵ) 

分 类 号：O657.31[理学—分析化学]