Determination of the Drug Naphazoline in Pharmaceutical Preparations by Heavy Atom-Induced Room-Temperature Phosphorescence

A simple, selective, and sensitive heavy atom-induced room-temperature phosphorimetric method (HAI-RTP) is described for the determination of naphazoline (NPZ) in pharmaceutical preparations. The phosphorescence signals are a consequence of intermolecular protection when analytes are, exclusively, in the presence of a heavy atom salt and sodium sulfite as an oxygen scavenger to minimize RTP quenching. This variable selection constitutes the basis of the HAI-RTP method for the determination of naphazoline (detection limit 43.5 ng/mL; 2.39% relative standard deviation at 500 ng/mL). The method has been applied to the analysis of pharmaceutical preparations.