Development of an Automatic Column Chromatography Separation Device for Metal Isotope Analysis Based on Droplet Counting

Abstract

A novel, simple, cost-effective, reliable, and practical automatic column chromatography separation device capable of simultaneously purifying samples for radiogenic and non-traditional stable isotope analysis has been developed. The device avoids the use of any pump and features eluent driving by the siphon effect (gravity) and quantitative control by infrared droplet counting. Several factors affecting the control of droplets were investigated, including types and concentrations of eluents and the height of the liquid level. Results showed that accurate dripping of the eluent could be readily achieved by controlling the number of droplets under selected conditions. The separation performance of the device was first demonstrated by the elution of Sr and Cd in synthetic matrix solutions. The recoveries of Sr and Cd samples were better than 87.6 and 95.0%, respectively, and the whole procedure blank was about 0.3 ng for Sr and 0.1 ng for Cd. Finally, the reliability of the device was further validated by the purification of Sr and Cd from different geological reference materials (NIST 2711a, Nod-A-1, BCR-2, and BHVO-2). The determined Cd and Sr isotope values agree well with their reference values within the uncertainty range. All these results clearly demonstrate the reliability and practicability of the proposed device, which provides a promising method for the automated purification of isotope samples.

Stable Isotope Fractionation of Metals and Metalloids in Plants: A Review

“…To aid such detailed and comprehensive experiments, improvements to sample throughput should be made. The efficiency of sample purification could be improved by (i) automated ion chromatography or sample purification systems ( Husson et al, 2015 ; Morgan et al, 2018 ; Kidder et al, 2020 ; Zhou et al, 2021 ) or (ii) using new generation MC-ICP-MS instruments that are equipped with high-resolution modes, quadrupole pre-mass filters or collision/reaction cells to reduce interferences (e.g., Christensen et al, 2018 ; Moynier et al, 2021 ).…”

Fast and highly sensitive Cd isotopic analyses in low-Cd complex samples with MC-ICPMS based on plasma electrochemical vapor generation

“…The efficiency of making Cd isotopic analyses by MC-ICPMS is mainly limited by lengthy chemical purification procedures [50]. The high tolerance for matrix elements and residual organics demonstrated by PEVG-MC-ICPMS enables simplification of the purification process without compromising measurement accuracy and precision, giving a rapid and accurate Cd isotopic analysis method.…”

An automated parallel multi‐channel chromatographic system for isotopic analysis – Demonstration considering Sr

“…These systems consist of an array of columns, and each sample was operated in a separate column to avoid cross-contaminations. For example, A COLUMNSPIDER system reported by [23], a Chem-CobOne by [24], a siphon effect, and an infrared droplet counting device by [25], consisted of 20, 12, and 21 columns, respectively. A crucial disadvantage of the open column systems is that the elution rate of each column is not consistent.…”