Assessment of In Situ Sorbent Formation Solid-Phase Extraction for the Determination of Cadmium in Natural Water Samples and Plant Leaves by Flame Atomic Absorption Spectrometry

A novel solid-phase extraction procedure was developed for the preconcentration and measurement of cadmium in plant leaves (lettuce and tobacco) and water samples utilizing flame atomic absorption spectrometry. This proposed method involves the in situ formation of an insoluble ion-pairing salt to be used as a sorbent. Cetyltrimethylammonium bromide was utilized as a cationic surfactant, and perchlorate was added as an ion-pairing agent. Cadmium(II) ions were selectively extracted after forming a complex with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol. The variables were optimized, and method validation was performed. The limit of detection and limit of quantification were, respectively, 0.31 and 1.1 μg/L. With a preconcentration factor of 40 and a relative standard deviation of 2.6%, the method demonstrates promise for detecting low levels of cadmium. The monitoring of cadmium in real samples was successfully carried out using the suggested approach.