Development and testing of a multi-element ICP standard

Abstract

Determination of the calibration dependence of spectrometers’ output signal on the content of the measured elements is of great importance for the metrological assurance of the high-precision inductively coupled plasma (ICP) massspectrometry and optical emission spectrometry methods. This paper presents the results of a study on establishing the certified values of reference material of composition of multi-element solution of metals intended for inductively coupled plasma methods (ICP-CRM solution Multi 1). The reference material (RM) is a solution with certified values of the mass fraction of metals: barium, cadmium, cobalt, lithium, lead, and zinc. The solution was packed in high-density polyethylene bottles with the capacity of 4, 8, 15, 30, 60 and 125 cm 3 . The certified value of the mass fraction of metals in the solution was established by the calculation and experimental procedure and confirmed by the GET 217-2018 State Primary Standard of Unit of Mass Fraction and Unit of Mass (Molar) Concentration of Inorganic Components in Aqueous Solutions Based on Gravimetric and Spectral Methods. The permissible certified values of the mass fraction of metals in the developed ICP-CRM are shown to range from 900 mg/kg to 1100 mg/kg. The authors have embarked on the study of the reference material by testing RMs for long-term stability and determination of the RMs’ expiration date. It is assumed that the expanded uncertainty of measurements of the certified value of the mass fraction of metals in the solution of the multi-element ICP-CRM solution Multi 1 will not exceed 0.5 %. The ICP-CRM solution Multi 1 can be used for ensuring the metrological traceability of measurements in inorganic analysis using ICP-MS and ICP-OES to the GET 217-2018. The developed solution will also allow one of the main advantages of these methods to be applied in routine analysis, namely the ability to quickly and simultaneously measure several elements in samples.