Determination of major and trace elements in plant samples by inductively coupled plasma optical emission spectrometry with deep eutectic solvent extraction based on choline chloride and carboxylic acids

A rapid, precise, and environmentally friendly approach utilizing an ultrasound assisted deep eutectic solvent-based extraction method was developed for the extraction of Ca, Fe, K, Mg, Mn, Na, P, S and Zn from plant samples. The investigation was conducted on deep eutectic solvents that are based on choline chloride and carboxylic acids. The determination of target analytes in the extracts was carried out using inductively coupled plasma-optical emission spectrometry (ICP-OES). The DESs based on malic acid were found to exhibit the highest extraction recovery values (95-106%). The parameters affecting the extraction of target analytes were optimized using standard reference materials. The target analytes can be effectively extracted from plant samples using 0.5 g of DESs and ultrasonication for 40 minutes. The determination results of the reference samples indicated that the relative error (RE) was below 15.1%, and the relative standard deviation (RSD) was less than 6.3%, demonstrating excellent accuracy and precision. The proposed method was employed to quantify target analytes in actual plant samples. The accuracy of this method was not significantly different from that of the microwave digestion method. The proposed method has been demonstrated to be a valid approach for the determination of target elements in actual plant samples.