Fluorimetric determination of methylmercury as an ion-association complex with rhodamine B in the presence of iodide

摘要

A fluorimetric method for the determin~tion of methylmercury was established. The method was based on the formation of anionic pair between iodide-methylmercury-rho- damine B in hydrochloric acid, which can be extracted with benzene. The fluorescence emission was measured at J.ex/J.em 575/590 nm, and the experimental variables and possible in- terference were studied. The linear calibration range was 4 x 10-8 mol/L -5 x 10-7 mol/L with a correlation coefficient of 0.9992. The detection limit was 1 :x lo-s mol/L. The method was used to determine methylmercury in human hair. The re- covery was in the range of 91% to 105% and the relative stan- dard deviation was 2.8%. The results agreed with those ob- tained by gas chromatography with electron capture detection.