High-Accuracy Determination of Potassium and Selenium in Human Serum by Two-Step Isotope Dilution ICPMS.

Jian Yang,Lixia Chi,Shengmin Li,Ilari Filponnen

doi:10.1155/2021/5533631

Abstract

A high-accuracy measurement technique for determining potassium and selenium in human serum was developed by using two-step Isotope Dilution Inductively Coupled Plasma-Mass Spectrometry (ICPMS) in this research. A more accessible method of the quadrupole ICPMS was employed in this research to achieve an equally high accuracy which had been achieved by a much more expensive method, namely, high-resolution sector field ICPMS (SF-ICPMS), with a comparatively easy and simple operation. In addition, we have evaluated the uncertainty of this method. The results showed that the determination limits of potassium and selenium in serum were 0.8 mg/kg and 2.7 μg/kg, respectively, and the precision for both measurements was lower than 0.2% and 0.7%. The measurement, when employed to measure potassium and selenium in standard materials NIST956D, NIST909C, and GBW09152, had caused a maximum deviation of less than 0.9%, within the stated uncertainty range of standard materials. The RELA international inter-laboratory comparisons of potassium in serum in 2018 conducted by our laboratory also yielded a satisfactory result.

Highlights

Isotope Dilution Inductively Coupled Plasma-Mass Spectrometry (ICPMS), with an edge over many conventional methods, has been recognized by CCQM as one of the top five methods with absolute measurement properties
Isotope Dilution ICPMS is achieved through the practice of balance weighing and the mass spectrometry measurement of isotope abundance, converting the chemical composition analysis into mass spectrometry measurement
Two-step Isotope Dilution ICPMS has been established in our laboratory to achieve high-accuracy determination of potassium and selenium in human serum. e reliability of this method has been verified by its employment to the analysis of standard materials and through the RELA comparison

Summary

Introduction

Isotope Dilution ICPMS, with an edge over many conventional methods, has been recognized by CCQM as one of the top five methods with absolute measurement properties. Isotope Dilution ICPMS is achieved through the practice of balance weighing and the mass spectrometry measurement of isotope abundance, converting the chemical composition analysis into mass spectrometry measurement. It has absolute measurement properties, and the values obtained can be traced directly to the international basic unit of the mass, namely, mole. In Isotope Dilution ICPMS, the isotope abundance ratio rather than the concentration of the sample is measured. Two-step Isotope Dilution ICPMS has been established in our laboratory to achieve high-accuracy determination of potassium and selenium in human serum. There are few reports about the reference method of selenium and potassium in serum by two-step isotope dilution mass spectrometry. There are few reports about the reference method of selenium and potassium in serum by two-step isotope dilution mass spectrometry. is method can be recommended as a traceable reference method for calibrating detection systems or assigning values to certified reference materials

Materials

Methods

Results and Discussion