Fluorimetric detection of hypochlorite using albumin stabilized gold nanoclusters

Development of simple and effective techniques for hypochlorite (HOCl) detection at trace levels are of great importance due to its wide spread use as disinfectant especially for water treatments including drinking water. A fluorescence 'turn-off' detection technique for HOCl based on bovine serum albumin (BSA) stabilized gold nanoclusters was developed. The fluorescence quenching of gold nanoclusters by HOCl is due to selective oxidation of amino acid residues in BSA that could be seen visually under UV lamp as color change within 2 min. The current method is rapid, simple and enables sensitive determination of HOCl with a detection limit of 0.1 × 10−6 M. The method showed high selectivity over other common ions present in the environment and was applied to detect HOCl in real water samples.