Deep eutectic solvent based liquid phase microextraction of nickel at trace level as its diethyldithiocarbamate chelate from environmental samples

A new and green deep eutectic solvent based liquid phase microextraction procedure (DES-LPME) has been developed for separation and preconcentration of nickel prior to micro-sampling flame atomic absorption spectrometric determination (MS-FAAS). Ni(II) was complexed with sodium diethyldithiocarbamate (NaDDTC) and was extracted to micro-volume DES phase. In this regard, tetra butyl ammonium chloride-decanoic acid component as 1:3 molar ratios was used to prepare DES. Analytical parameters such as pH of sample solution, sample volume, volume of DES and matrix effect that would affect the recoveries of nickel(II) were optimized. Quantitative recovery values for Ni(II) ions were obtained at pH 3.0. The preconcentration factor (PF) was calculated as 60. The limit of detection (LOD) and limit of quantification (LOQ) were determined to be as 0.13 mu g L-1 and 0.43 mu g L-1 respectively. The relative standard deviation (% RSD) was 3.2%. The validation of the developed method was proved by the analysis of the certified water reference materials and addition-recovery test. The presented deep eutectic solvent based liquid phase microextraction method (DES-LPME) was successfully applied for determination of nickel in some water and food samples from Turkey