Author/Editor		Istenič, Simon; Cvetko, Erika; Zabret, Joži; Stopar Pintarič, Tatjana; Umek, Nejc
Title		Determination of bupivacaine tissue concentration in human biopsy samples using high-performance liquid chromatography with mass spectrometry
Type		članek
Publication year		2021
Volume		str. str.
ISSN		1099-0801 - Biomedical chromatography : BMC
Language		eng
Abstract		In the present study, we developed a simple and rapid analytical method for the quantification of bupivacaine hydrochloride in human biopsy samples of adipose, muscle, neural, connective and cartilage tissue using liquid chromatography-mass spectrometry. Anaesthetics were extracted from the tissue samples using 0.1% formic acid in acetonitrile for protein denaturation and hexane for lipophilic impurities removal. Analytes were separated adequately on Phenomenex Luna Omega polar C18 column using gradient mobile phase 0.1% formic acid in water and 0.1% formic acid in acetonitrile. The lower limits of quantification were <- 97 ng g-1 tissue for all studied tissues. Intra-day recoveries were between 48.2-82.1% with relative standard deviations (RSDs) between 1.47-14.28%, while inter-day recoveries were between 52.2-77.6% with RSDs between 2.98-14.79%. The calibration curve showed linear fit with R2 higher than 0.99 in concentration range from 0.16-100 [micro]g g-1 . Lidocaine hydrochloride was tested as internal standard because its recoveries and matrix-effects were comparable to bupivacaine hydrochloride. Post analytical corrections of measured bupivacaine tissue concentrations can accordingly be made based on recovery of lidocaine as internal standard, with recoveries between 51.2-86.9% and RSDs between 1.99-16.88%. The developed method could be used to study time-dependent spread of bupivacaine locally or to more distant locations across tissue barriers.
Keywords		bupivakain lidokain vzorec biopsije bupivacaine lidocaine biopsy sample