Use of a microcolumn packed with modified carbon nanofibers coupled with inductively coupled plasma mass spectrometry for simultaneous on‐line preconcentration and determination of trace rare earth elements in biological samples

Abstract

In this work, a new method was developed for the determination of trace rare earth elements (REEs) in biological samples by inductively coupled plasma mass spectrometry (ICP-MS) after preconcentration on a microcolumn packed with modified carbon nanofibers (CNFs). CNFs oxidized with nitric acid have been proved to possess an exceptional adsorption capability for REEs due to their surface functionalization. The effects of the experimental parameters, including pH, sample flow rate and volume, elution solution and interfering ions, on the recoveries of the analytes have been investigated systematically. A 100-fold enrichment factor was obtained. The adsorption capacity of CNFs was found to be 18.1, 19.3, 23.6, 17.6, 22.3 and 19.5 mg/g for La, Ce, Sm, Eu, Dy and Y, respectively. Under the optimum conditions, the detection limits of this method ranged from 0.2 pg/mL (Dy) to 1.2 pg/mL (Ce) with an enrichment factor of 15-fold, and the relative standard deviations (RSDs) for the determination of REEs at the 1.0 ng/mL level were less than 4% (n = 9). This method was applied to the analysis of trace REEs in a real sample of human hair with recoveries of 95-115%. In order to validate the proposed method, a certified reference material of human hair (GBW 07601) was analyzed with satisfactory results.

Solid-phase extraction of Cu, Co and Pb on oxidized single-walled carbon nanotubes and their determination by inductively coupled plasma mass spectrometry

“…The surface atoms are unsaturated, possess highly chemical activity, and can easily bind with other atoms. Consequently, interesting in adapting nanometer material as a new adsorbent for the preconcentration and separation of substance has increased significantly [18][19][20][21][22][23][24]. Single-walled carbon nanotubes (SWNTs), as an interesting member in carbon family, have been predicted and experimentally proved to possess exceptional mechanical properties, high chemical stability and a large specific surface area, which make them a promising candidate as adsorbers [25].…”

Recovery of Rare Earth Elements by Carbon-Based Nanomaterials—A Review

“…Table 7 represented the studies of the REEs recovery using the other types of carbon materials which do not belong to the graphene or carbon nanotubes families (activated carbon, fullerenes, carbon dots, mesoporous carbon, carbon nanofibers and carbon black). Again, this review is only focused on batch experimental studies whereby there are a few studies in the literature that are not been explored in this review because they are column experiments [38,116,117,118]. However, it was possible to verify that carbon nanotubes and carbon nanofibers are the most used materials for column experimental studies.…”

Preparation, characterization and application of Saussurea tridactyla Sch-Bip as green adsorbents for preconcentration of rare earth elements in environmental water samples

“…After elution with 0.5 mol L −1 HNO 3 , the adsorption capacity values for Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu were 62.2, 130, 101, 104, Table 6 Analytical results of REEs in environmental water samples (μ = mean ± uσ, n = 3, P = 95%, ng mL −1 ). [13,20,22,[44][45][46], the adsorption capacity of STSB for each REE is obviously higher. Under the optimized condition, the adsorption and desorption of target REEs on STSB adsorbent pretreated with 2 mol L −1 NaOH were processed repeatedly and continuously, and the stability of the adsorbent was examined by monitoring the recovery of REEs.…”