Matrix overcompensation calibration: a new strategy to correct matrix effects of carbon origin in multielemental analysis by inductively coupled plasma mass spectrometry

Authors: Chen, Guoying; Lai, Bun-Hong

Submitted to: Journal of Analytical Atomic Spectrometry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/2/2024
Publication Date: 5/4/2024
Citation: Chen, G., Lai, B. 2024. Matrix overcompensation calibration: a new strategy to correct matrix effects of carbon origin in multielemental analysis by inductively coupled plasma mass spectrometry. Journal of Analytical Atomic Spectrometry. https://doi.org/10.1016/j.aca.2024.342675.
DOI: https://doi.org/10.1016/j.aca.2024.342675

Interpretive Summary: Organic matrix components may interfere with elemental analysis by inductively coupled plasma mass spectrometry (ICPMS). Correction strategy is needed to achieve reliable quantification. A new matrix overcompensation calibration (MOC) is developed to correct matrix effects of carbon origin. Juice samples were diluted by 50 folds; 5% ethanol was added to dominate matrix effects from native components. A calibration curve built from a likewise treated standard series was applied to juices of diversified origins. This MOC strategy enabled multielemental ICPMS analysis in juices after simple dilution. Validation was carried out by spike-recovery study and comparison with standard addition calibration and microwave-aided digestion.The new methodology simplifies sample preparation and elemental analysis in foods and other organic materials.

Technical Abstract: Organic matrix components may interfere with elemental analysis by inductively coupled plasma mass spectrometry. Matrix effects can be mitigated by separation of target analytes from concomitant components at the cost of time, labour, and resources. Alternatively, correction strategy can be applied including matrix-matched calibration (MMC), standard addition calibration (SAC), internal standardization calibration (ISC), or isotope dilution (ID). When sample matrix cannot be closely matched or the interferants are uncertain, SAC is universally applicable but requires a calibration curve for each sample, productivity thus suffers. A new approach, matrix overcompensation calibration (MOC), was developed in this laboratory to correct matrix effects of carbon origin. ISC was implemented using Ge, Rh, and Ir. Juice samples were diluted 1:50 in 1% HNO3'0.5% HCl'5% ethanol. Ethanol (5%) was added as matrix markup compound to dominate matrix effects from concomitant components. A standard series was treated likewise to construct a calibration curve applicable to juices of diversified crop, geographical, and manufacturer origins. This MOC strategy enabled quantitative analysis of As, Se, Cd, and Pb in juices by dilute-and-shoot ICPMS. Validation of this protocol was carried out by spike-recovery study and comparison with SAC and microwave-aided digestion.