Pipette Tip Solid-Phase Extraction Combined with Fluorescence Spectroscopy for Determination of Selenium in Green Tea Samples

Abstract

Abstract In this study, the custom-built pipette-tip solid phase extraction (PT-SPE), was used for pre-concentrating the selenium (Se) in green tea samples. The PT-SPE was prepared using a pipette tip and C18 as the adsorbent that was placed between glass wool. This method afforded several advantages in terms of efficiency of extraction time (8 min), sample (2 mL), and solvent (1 mL) volumes with less wastage of solvent. Under optimal conditions of extraction, this method yielded good linearity (r2=0.998) for the Se calibration curve and good limit of detection (0.2 μg/L) and quantification (0.6 μg/L). The standard addition method was used to remove the matrix effect. The recovery percentages of tea samples spiked with different Se concentrations ranged from 97.7 to 106.0%, indicating that the proposed method would be suitable for the determination of Se in green tea samples.