Direct multi-elemental analysis of whole blood samples by LA-ICP-MS employing a cryogenic ablation cell

Abstract

A simple and rapid method for the multi-elemental analysis of whole blood samples by CLA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry with a cryogenic ablation cell) is described. The whole blood samples were frozen with a designed Peltier-cooled ablation cell, followed by the direct analysis of multiple elements by LA-ICP-MS without any pretreatment. Comparing the precision of time-resolved signals during laser ablation processes between the room temperature (20 °C) and low temperature (−20 °C), the precision was significantly improved, and the RSD was reduced from 14.2 (Mn)–36.4% (Al) to 1.9 (Zn)–6.3% (Al) with six times parallel determination. To improve the sensitivity of the analytical signals, the smaller inner volume ablation cell was used, and the signal intensity was increased by three times compared with the standard commercial ablation cell. CRM Trace Elements Whole Blood L-3 was used as the matrix-match external standard and Rh as an internal standard for the quantitative calibration of whole blood samples. The limits of detection (LODs) for most elements ranged from 0.17 μg L⁻¹ (Mn) to 0.94 μg L⁻¹ (Cr). The accuracy and precision were validated by three strategies, including a standard addition recovery experiment, determination of reference materials, and comparison of different analytical methods. All results showed there were excellent accuracy and precision in the proposed method. A microwell plate was used for high-throughput analysis. The analytical time of each sample was less than 1 min, and the sample consumption was only about 10 μL. With the advantages of high-precision, high-throughput, and small sample consumption, the proposed method was promising for applications in health screenings and disease risk assessments of large populations through blood analysis.