NiO-SnO₂ nanocomposite as an adsorbent for the preconcentration of manganese ions in chamomile tea extract

Matricaria chamomilla L., referred to as chamomile, is a well-known medicinal plant that is widely distributed throughout the world. In this study, a novel NiO-SnO₂ nanocomposite- assisted preconcentration method was established for efficient extraction and separation of manganese ions from chamomile tea extract. This preconcentration method was coupled with flame atomic absorption spectroscopy (FAAS). NiO-SnO₂ nanocomposites were synthesized using simple one-pot co-precipitation procedure and calcined at 650 °C to obtain nanoparticles with sizes below 100 nm. X-ray diffraction (XRD) analysis indicated that the crystallite size of NiO-SnO₂ nanocomposites was estimated to be 46.03 nm using the Monshi-Scherrer equation. The LOD (limit of detection) and linear working range were determined as 3.6 μg/L and 10-100 μg/L, respectively. The proposed method was successfully validated, and recoveries ranged from 87.2 %-117.0 %. NiO-SnO₂ nanocomposites represent a promising low-cost adsorbent for the preconcentration and subsequent determination of other heavy metal ions in diverse herbal extracts.