Received: 9 February 2026
Принято: 17 February 2026
Published online: 27 February 2026
УДК: 543.544.5:543.51:615.07
DOI: 10.53511/pharmkaz.2026.1.2
VALIDATION OF A QUANTITATIVE METHOD FOR DETERMINATION OF URSODEOXYCHOLIC ACID IN HUMAN PLASMA USING LC-MS/MS
Tumabayeva A.M. ¹, Duisenova M.U. ², Yelzhasova A.M.³, Myzhanova N.K. 4, Shnaukshta V.S. 5,Tilekeeva U.M.6
¹’²’³,4,5 National Center for Expertise of Medicines and Medical Devices” of the Committee for Medicial and
Pharmaceutical Control of the Ministry of Health of the Republic of Kazakhstan, Almaty, Kazakhstan
6 Kyrgyz State Medical Academy named after I.K. Akhunbaev, Bishkek, Kyrgyzstan
Introduction: A bioanalytical method for the quantitative determination of ursodeoxycholic acid
(UDCA) in human plasma has been developed and validated using high-performance liquid
chromatography coupled with tandem mass spectrometry (LC–MS/MS) with a single-step protein
precipitation procedure. The method was validated over a concentration range of 150–12,000 ng/mL, with a lower limit of quantification (LLOQ) of 150 ng/mL. The chromatographic run time was 4 minutes, and the method was successfully applied to the analysis of plasma samples in a
bioequivalence study.
Materials and Methods: UDCA concentrations were determined using LC–MS/MS. During
method validation, the following parameters were evaluated: selectivity, linearity, carry-over, lower limit of quantification (LLOQ), accuracy, precision, and stability.
Results: The method demonstrated high selectivity, excellent linearity (r² ≥ 0.995), and acceptable
accuracy and precision, not exceeding ±15 % for quality control samples and ±20 % at LLOQ, in
21 accordance with established acceptance criteria. Carry-over was within acceptable limits, and the method showed satisfactory stability under the tested conditions.
Discussion: The validated method is sufficiently sensitive for the determination of UDCA in human
plasma and can be successfully applied for the analysis of plasma samples in pharmacokinetic and bioequivalence studies.
Keywords: ursodeoxycholic acid, LC–MS/MS, bioanalytical validation, bioequivalence
