Improved fluorimetric determination of dissolved aluminium by micelle-enhanced lumogallion complex in natural waters

A modification of the aluminium-lumogallion fluorescence measurement in the presence of the non-ionic surfactant Triton X-100 is presented. The detect ion limit for dissolved Al is 0.7 nM, with a relative standard deviation of 3.6% at an Al level of 5.0 nM. Compared with previously reported methods i n the literature, the method described here is free from matrix effects and can be used for the determination of aluminium in fresh, estuarine and sal ine waters. The interferences from iron and fluoride were minimized by the addition of o-phenanthroline and Be2+, respectively. The analysis of NIST S RM 1643C and PRC standard 2430101 by the proposed method provides results c onsistent with the certified values. A successful inter-laboratory calibrat ion exercise also demonstrates the merit of the proposed method for the det ermination of Al in environmental and marine sciences.