Analytical Method Validation for Quantitation of Multi-Toxic Metals using Microwave-assisted Digestion with ICP-MS analysis for Mangifera indica Matrix

Abstract

The aim of this research work is to develop and validate the analytical method followed by the microwave-assisted digestion method for the quantitative analysis of the toxic metals in Mangifera indica matrix by using ICP-MS, which will be used for field sample analysis. The ICP-MS technique has several applications such as the determination of single elements, and multi-element analysis in different matrices. The use of pesticides may generate residue in fruit which makes them risky to be administered. Thus, it is essential that these residues must be detected and quantified. ICP-MS plays a significant function in the quantitation of elemental residues. To determine toxic and essential elements in the Mangifera indica matrix at the different maturity levels by using Inductively coupled plasma mass spectrometry (ICP-MS) equipped with microwave digestion is considered an excellent tool for the digestion of many samples analysis. The analytical method developed and validated for the quantitative analysis for the determination of toxic metals (Chromium (Cr), Manganese (Mn), Nickel (Ni), Copper (Cu), Arsenic (As), Cadmium (Cd), Lead (Pb). Numerous parameters have been evaluated for the validation of the method, namely: matrix effect, linearity, the minimum detection limit (LOD), the limit of quantification (LOQ), precision, accuracy, extraction solution stability, and standard solution stability. Matrix effects (± 20.0%) were not considered significant. The linearity concentrations range (0.1 to 32.0 µg/L) were drawn and the value of correlation coefficient (r) in linearity was ≥ 0.99. The precision % RSD was 10.0% and accuracy (% recovery) was 70 to 110% of the fortified concentration at LOQ level and 10 times LOQ Level. The final extraction stability was within the limit of 70 to 120% of the test item concentration with % RSD (20%). The standard solution stability % Difference was ± 10, it is concluded that the standard solution was stable throughout the experiment phase. The validated analytical method will be used for the quantitation of the toxic metals in Mangifera indica matrix for monitoring and further evaluation purpose at the lower residual level.