Spectrofluorimetric determination of aluminum in drinking waters by sequential injection analysis Original Research Article

A selective procedure for the determination of Al3+ in drinking and natural waters is proposed. The analytical procedure is based both on the complex formation between Al3+ and 8-hydroxyquinoline-5-sulfonic acid (HQS) and on a fluorimetric detection of the complex. The reaction was carried out in presence of thioglycolic acid as a masking agent. This procedure has been adapted to a sequential injection analysis (SIA) system. Operative conditions both for batch and SIA procedures were investigated including reagent concentration, volumes, pH and wavelengths used for the fluorimetric detection. Batch procedure allows determination of Al3+ at ppb level (LOQ: 2.8 μg l−1) within a working range of 2.2–300 μg l−1. The SIA procedure was successfully employed for the determination of Al3+ in several commercial drinking and tap waters.