Development of a fast LC-MS/MS method for quantification of rilmenidine in human serum: elucidation of fragmentation pathways by HRMS

• Published in: Journal of mass spectrometry. Vol. 45; no. 10; pp. 1179 - 1185
• Main Authors: Chytil, Lukáš, Cvačka, Josef, Marešová, Věra, Štrauch, Branislav, Widimský, Jiří Jr, Štícha, Martin, Slanař, Ondřej
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-10-2010; Wiley
• Subjects: Analysis; Antihypertensive Agents - blood; Antihypertensive Agents - chemistry; Antihypertensive Agents - pharmacokinetics; Biological and medical sciences; Chromatography, Liquid - methods; Drug Stability; Fragmentation; General pharmacology; HRMS; Human; Humans; LC-MS/MS; Least-Squares Analysis; Linearity; Liquid-liquid extraction; Liquids; Mass spectrometry; Medical sciences; Oxazoles - blood; Oxazoles - chemistry; Oxazoles - pharmacokinetics; Pathways; Pharmacology. Drug treatments; quantification; Reproducibility of Results; rilmenidine; Sensitivity and Specificity; serum; Serums; Solid Phase Extraction; Tandem Mass Spectrometry - methods; Solid phase extraction; Biological fluid; Tandem mass spectrometry; Agonist; Chemical analysis; HPLC chromatography; Fragmentation pattern; Solvent extraction; Electrospray; Blood; Chemical enrichment; HRMS; LC-MS/MS; Sample preparation; Quantitative analysis; α2-Adrenergic receptor; Human; Validation; quantification; Rilmenidine; Liquid liquid extraction; Coupled method; Oxazoline derivatives; Antihypertensive agent; α-Adrenergic receptor agonist; Blood serum; serum
• ISSN: 1076-5174; 1096-9888; 1096-9888
• DOI: 10.1002/jms.1809

Rilmenidine is an alpha 2 adrenoreceptor agonist used in the treatment of mild and moderate hypertension. In this study, a fast and accurate liquid chromatographic method with tandem mass spectrometric detection has been validated in order to assure quantification of rilmenidine in human serum. The fragmentation pathway of protonated rilmenidine was studied using high-resolution mass spectrometry (HRMS). This study compared selectivity, linearity, accuracy, precision, extraction efficiency, matrix effect and sensitivity using common liquid-liquid extraction (LLE) and solid-phase extraction (SPE) procedures. The limit of quantitation for both extraction techniques was 0.1 ng/ml. Several differences between the LLE and SPE have been observed in terms of linearity, accuracy, precision and matrix effect. Additionally, the advantages of SPE included less manual work load and increased recovery of rilmenidine in human serum to approximately 80% (LLE, 57%). The developed method involving SPE was found to be accurate (relative error (RE) < 5%), reproducible (relative standard deviation, RSD < 7%), robust and suitable for quantitative analysis of rilmenidine in serum samples obtained from patients under antihypertensive treatment. Copyright © 2010 John Wiley & Sons, Ltd.