ABSTRACT
A highly sensitive, selective and accurate method has been developed to determine ultra trace amounts of copper(II) by solid-phase extraction (SPE). The following parameters such as pH, concentration of the reagent, Triton X-100, reversed-phase Amberlite IR-120, equilibrating temperature and centrifuging time were evaluated to enhance the sensitivity and extraction efficiency of the proposed method. The method has been based on copper(II) and 4-((furan-2-ylmethylene) amino)-5-methyl-4 H-1,2,4-triazole-3-thiol (FAMT) reaction, followed by solid-phase extraction (SPE) of Cu(II)-FAMT with a reversed-phase Amberlite IR-120. This was performed by using borate buffer solution of pH 7.6 in the presence of Triton X-100 medium. FAMT reacts with copper(II) to form a deep green complex with molar ratio of (2: 1) (FAMT: copper). An enrichment and improvement factor of 200 and 540, respectively, were obtained by elution of the complex from the resin with a minimal amount of dimethylsulfoxide (0.5 mL). The molar absorptivity of the complex was 6.49 × 106 L mol−1 cm−1 at 499 nm. Beer’s law was obeyed in the range 5.0–190 ng mL−1 of the measured solution. After optimising the instrumental and experimental parameters, the maximum values for quantification and detections limits of 100 mL sample system were 5.40 and 1.64 ng mL−1. The suggested method has been successfully applied for determination of copper ions in various environmental (water, vegetables, food, and biological) samples.
Disclosure statement
No potential conflict of interest was reported by the author(s).