Fluorescence sensing of arsenate at nanomolar level in a greener way: naphthalene based probe for living cell imaging

Naphthalene–salisaldehyde conjugate (NAPSAL) is established as a novel arsenate (H₂AsO₄⁻) selective ‘turn-on’ fluorescence probe. It can detect as low as 5 × 10⁻⁹ M H₂AsO₄⁻ in HEPES buffered EtOH : water (0.1 M, 1 : 9, v/v, pH 7.4). Trace level H₂AsO₄⁻ in drinking water samples is measured using standard addition method. Intracellular arsenate in Candida albicans, grown in arsenic contaminated water of Purbasthali has successfully been detected under fluorescence microscope.