An ion-pair HPLC fluorimetric determination of Al(III) at trace level has been developed, with salicylaldehydebenzoylhydrazone (SAB) as a precolumn reagent. The highly fluorescent AlSAB chelate (λex 390.8 nm, λem 458.1 nm) is separated on a LiChroCART RP-18 column with an eluent consisting of 3.1 × 10-m tetrabutylammonium bromide, 1 × 104̄m disodium EDTA and 5 × 10-3m sodium acetate in aqueous 42% w/w acetonitrile solution. The detection limit for Al is 1.5nM (40 pg/ml) in a 100-μl injection. The spectrophotometric detection limit at 390 nm is 0.3 ng/ml for 0.005 full-scale absorbance range. The selectivity is excellent and the method is useful for routine quality-control applications, such as determination of Al in tap water and in alkali pellets (LiOH, NaOH and KOH).
ASJC Scopus subject areas
- Analytical Chemistry