Espectrometria de massas com ionização a partir de partículas magnéticas (MPS-MS) para análise de anti-hipertensivos de plasma humano

Abstract

Recently developed in our research group, magnetic particle spray mass spectrometry (MPS-MS) was used to analyze antihypertensive drugs in human plasma samples. The analyte's dispersive solid phase extraction (d-SPE) technique was applied using magnetic molecularly imprinted polymer particles (M-MIP). The particles were attached to a metallic probe positioned at the entrance of the mass spectrometer. Then, a solvent was added, and a Taylor cone formed around the particles due to the high voltage applied. Thus, the analytes were efficiently desorbed/ionized and subjected to analysis in a triple quadruple mass spectrometer. M-MIP was produced using oxprenolol as a model molecule and was then characterized and used to evaluate the performance of MPS-MS in the analysis of the beta-blocker’s atenolol, metoprolol, labetalol, propranolol, nadolol and pindolol in human plasma. M-MIP showed satisfactory selectivity for beta-blockers in comparison with non-analogous molecules, in addition to exhibiting a heterogeneous surface on which, according to isotherm studies, a monolayer adsorption process occurs. Chemisorption was the predominant interaction between M-MIP and analytes, as indicated by adsorption kinetic experiments. The analytical curves resulted in linearities (r2 greater than 0.98), and the limits of quantification for all analytes were three µg L-1. Precision (expressed as relative standard deviation) and accuracy (expressed as relative error) varied between 3.95 and 21.20% and between -17.05 and 18.93%, respectively. The MPS-MS technique has proven to be extremely simple, sensitive, and advantageous compared to conventional approaches. Analyzes are quick, do not require chromatographic separation, and have a minimum of ion suppression. The sample volumes, solvent, and sorbent mass used in MPSMS were significantly reduced, in full compliance with the principles of green chemistry. MPS-MS presents a new perspective on the interaction between sample preparation and ambient ionization mass spectrometry, with potential for use with other sorbents and different samples and analytes.