Abstract:

Effective strategies are required to address food safety issues related to the illegal addition of antihypertensive drugs to food and claims of antihypertensive function. In this study, a novel ultra-high performance liquid chromatography-triple-quadrupole mass spectrometry (UHPLC-MS/MS) method was developed for the simultaneous determination of three antihypertensive drugs (azilsartan, candesartan cilexetil, and lacidipine) in 12 food matrices (pressed candies, solid beverages, alternative teas, tea drinks, biscuits, jellies, mixed liquors, oral liquids, medicinal teas, tablets, hard capsules, and soft capsules). Initially, mass spectrometry parameters, such as the collision energies of the three antihypertensive drugs, were optimized. Subsequently, the response intensities and chromatographic separation conditions of the three drugs in different mobile phases were compared. In addition, to enhance the recoveries, various extraction solvents and purification methods, including solid-phase extraction (SPE) columns and the QuEChERS technique, were investigated. In the developed method, sample determination involved three steps. First, the sample was extracted using 0.2% (v/v) formic acid in acetonitrile and then filtered using high-speed centrifugation, in addition, the extracted solution of alternative tea and medicinal tea was purified using the QuEChERS technique. Second, the supernatant was diluted with water, and filtered through a 0.22 μm polytetrafluoroethylene (PTFE) membrane. Finally, the analytes were separated on an Agilent Eclipse Plus RRHD C₁₈ column (50 mm×2.1 mm, 1.8 μm) using a 5 mmol/L ammonium formate aqueous solution and acetonitrile as the mobile phases under gradient elution conditions and then detected using UHPLC-MS/MS with positive electrospray ionization (ESI) in the multiple reaction monitoring (MRM) mode. Quantitative analysis was performed using a matrix-matched external standard method. Methodological validation showed good linear relationships for all three antihypertensive drugs in the investigated concentration ranges, with correlation coefficients (r²) greater than 0.996. The limit of detection (LOD) and limit of quantification (LOQ) of lacidipine were 0.02 mg/kg and 0.04 mg/kg, respectively, whereas those of the other two drugs were 0.01 mg/kg and 0.02 mg/kg, respectively. In the 12 food matrices, the average recoveries of the drugs ranged from 86.6% to 107.5% with relative standard deviations (RSDs) of 1.1%-10.9% (n=6) at low, medium, and high spiked levels. Furthermore, this method was successfully applied to the analysis of real food samples. Overall, the newly developed method is simple, rapid, sensitive, accurate, and suitable for the qualitative and quantitative determination of antihypertensive drugs in different food matrices. This work could provide technical support for food safety agencies in implementing measures against the illegal addition of antihypertensive drugs to food.

Key words: ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS), antihypertensive drugs, azilsartan, candesartan cilexetil, lacidipine, foods