Preconcentration of tellurium using magnetic hydrogel-assisted dispersive solid-phase extraction and its determination by slotted quartz tube-flame atomic absorption spectrophotometry

In this study, a simple and cheap magnetic chitosan hydrogel-based dispersive solid-phase extraction (MCH-DSPE) method was developed for the determination of tellurium in wastewater, tap water and mineral water samples before its determination by slotted quartz tube-flame atomic absorption spectrophotometry (SQT-FAAS). Important parameters that affect the extraction procedure were investigated. All the system parameters such as buffer pH and volume, hydrogel amount, mixing type and period and eluent volume were optimized to increase the accuracy and sensitivity of the developed method. Under the all optimum conditions, a 78.9-fold improvement was achieved in the detection power of the conventional flame atomic absorption spectrophotometry. The limit of detection (LOD) and limit of quantification (LOQ) values were calculated as 0.019 mg L⁻¹ and 0.063 mg L⁻¹, respectively. In order to test the applicability of the method, recovery studies were carried out in mineral water, tap water and wastewater samples, and the calculated recovery results were found to be about 100%. The results showed that magnetic chitosan hydrogels were used as sorbent materials in dispersive solid-phase extraction as a simple, environmentally friendly, rapid and low-cost preconcentration process.