The direct quantification by glow discharge mass spectrometry with the universal relative sensitivity factors without matrix-matched standards

Direct measurement of the elemental components of bulk conductors or semiconductors is the main application area of direct current glow-discharge mass spectrometry (dc-GDMS). The quantification by GDMS usually requires the matrix-matched standards to obtain the relative sensitive factors (RSFs) of the target elements. Unfortunately, the matrix types of the analytes are far beyond the available matrix-matched standards. To overcome this limitation of GDMS, we attempted to establish a direct quantification method by GDMS with a set of universal RSFs (u-RSFs) instead of the matrix-matched standards. To explore the intrinsic relationship between the RSFs and the operational parameters of GDMS, we studied the impact of the discharge current, discharge voltage, discharge gas flow rate, and the ion transmission system voltage on the RSFs of the representative elements with a GDMS instrument. Only the discharge gas flow rate was identified significant on RSFs. Based on the optimum parameters, a set of u-RSFs were obtained by averaging the RSFs in certified reference materials (CRMs) covering most common matrixes. The direct quantification by GDMS was accomplished by u-RSFs. This method was further validated in several scenarios, and the accuracy of 10%~30% was achieved.