Improving methods for sample preparation of biological fluids by inductively coupled plasma mass spectrometry

This study presents the results of analyzing biological fluids using Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after applying various sample preparation methods. Optimal conditions for preparing biological fluids have been identified, which help minimize matrix effects and improve measurement accuracy. The most effective methods were selected considering the specifics of matrices and their interactions with analytical equipment. The study evaluated the contributions of spectral interferences to the analytical signal when using ICP-MS. It was found that the physical properties of acid solutions, such as viscosity, surface tension, density, and volatility, significantly affect the analysis results, introducing additional interferences and data distortions. The use of internal standards to eliminate spectral interferences was investigated. Criteria for choosing internal standards were established based on proximity to ionization potentials and mass characteristics, which allows for more accurate result correction and minimizes interference effects. Additionally, it was discovered that polyatomic ions play a significant role in enhancing analyte signals. This influence is due not to the background levels of elements in the samples or reagents, but to ions formed from matrix components in the samples. The study demonstrated that isobaric interferences caused by polyatomic ions significantly impact analytical accuracy. These findings contribute to improving sample preparation and analysis methods for biological fluids using ICP-MS, leading to more reliable and accurate measurements of element concentrations.