Determination of trace indium in urine after preconcentration with a chelating‐resin‐packed minicolumn

Abstract

A simple and rapid chelating-resin-packed column has been developed for preconcentration of trace indium in biological samples. A large-sized urine sample was pumped through a minicolumn at a flow rate of 1.0 mL/min by using a peristaltic pump, and the eluents were analyzed using graphite furnace atomic absorption spectrometry (GFAAS). Four commercially available chelating resins including Chelex-100, Amberlite IRC-50, Duolite GT-73, and Celite 545-AW were studied for evaluating the indium sorption performance. Several parameters, such as pH, resin amount, eluent volume, eluent flow rate, and the volume of sample, were investigated and optimized. A 100-200 mL of the sample was loaded into a column containing 1.2 g of wet Chelex-100 and subjected to the ion-exchange procedure. The retained analytes were eluted with 5.0 mL of 0.1 M HNO(3) and quantified by GFAAS. The correlation coefficient in the range 10-250 ng/mL was of 0.9994. The limit of detection of the proposed method was 2.75 ng/mL. The method developed was successfully applied to analysis of spiked urine samples with good recoveries of 93-103% (n = 6) and reproducibility (relative standard deviation < 4.9%). The accuracy of procedure was confirmed by indium determination in spiked certified reference materials.

Rapid magnetic solid‐phase extraction of Congo Red and Basic Red 2 from aqueous solution by ZIF‐8@CoFe2O4 hybrid composites

“…Ten milligrams of as-prepared ZIF-8@CoFe 2 O 4 material was placed in a 15 mL glass vial, then, 5 mL of CR (30, 60, 90, and 120 mg/L) or BR2 dye (4,8,12,16, and 20 mg/L) aqueous solution of different concentration was added to the vial and sonicated for 15 min at room temperature at pH of 7.…”

“…The time for MSPE of CR and BR2 was set to 15 min by 10 mg of ZIF-8@CoFe 2 O 4 at a fixed pH of 7, which is also the same in the following adsorption kinetics experiments. Various concentrations of CR (30, 60, 90, 120, and 150 mg/L) and BR2 solution (4,8,12,16, and 20 mg/L) were used to obtain the equilibrium data. The fitting results and calculated constants for the three isotherm models along with R 2 values are presented in Supporting Information Table S1, Supporting Information Figs.…”

“…The adsorbent is the most important component in the process of SPE. Currently, many types of adsorbents have been used for SPE [2][3][4][5][6][7][8][9][10], such as carbon nanomaterials [2], resin [3,4], and polymer materials [5][6][7], etc.…”