Development and validation of a sensitive and selective LC—MS/MS method for the determination of an antimalarial drug candidate in rat plasma, and its application to a preclinical pharmacokinetic study

Abstract

Summary. An accurate and reliable LC-MS/MS assay was firstly developed and validated for quantitative determination of a new antimalarial prototype drug, 3β-hydroxyurs-12-en-28-oic acid (LAFIS 01), in rat plasma. Dexamethasone was employed as internal standard. Simple protein precipitation by acetonitrile for the sample preparation was used. Effective separation was achieved with Phenomenex Luna C 18 (50 × 2 mm, 5 μm) column. The mobile phase consisted of (A) water and (B) acetonitrile, both containing 0.1% acetic acid, delivered by gradient elution. The column temperature was maintained at 40 °C. The LAFIS 01 was monitored by electrospray ionization interface, operating in the negative mode (ESI−) in multiple reactions monitoring (MRM), checking the transitions 455 > 455 for LAFIS 01 and 451 > 361 for the IS. Once LAFIS 01 demonstrated low fragmentation by collision-induced dissociation (CID) nonpresenting abundant highintensity fragments to meet the desired concentration levels quantification, only pseudomolecular ion was monitored. The flow rate was 500 μL min −1 . The lower limit of quantitation achieved was 10 ng mL −1 and linearity was observed from 10 to 500 ng mL −1 . The relative standard deviation (RSD) values of the intra-and inter-assay precisions of the method were below 8.42 and 7.94%, respectively. The accuracy ranged from 92.05 to 102.94%. The extraction recovery of LAFIS 01 and IS was up to 90%. The method showed linearity, precision, accuracy, sensitivity, and stability required to quantify LA-FIS 01 in preclinical pharmacokinetic study.

Simultaneous Determination of Combined and Free Concentrations of Atorvastatin and its Major Metabolite in Vitro and in Vivo Based on Ultrafiltration Coupled with UPLC-MS/MS Method: Application to Protein Binding Rates and Metabolism Ability Study in Uremic Hemodialysis Patients.

“…Post-preparative stability was determined by assaying the 3 QC samples in autosampler at +4°C by injecting extracts immediately after preparation and re-injecting 2 and 12 hours later; Long-term stability was determined from serum samples stored at -80°C for 30 days [12] .…”

Bioanalytical LC-QTOF/MS Method for a N-phenylpiperazine Derivate (LQFM05): An Anxiolytic- and Antidepressant-like Prototype Drug Applied to Pharmacokinetic and Biodistribution Studies

“…Preclinical pharmacokinetics studies are key aspects of the new drug development phase as a way of identifying an adequate bioavailability profile, tissue distribution and excretion rates. Furthermore, it can support data on dosage schedules, pharmacological information, and possible toxicity [ 5 , 6 , 7 ]. In this sense, a reliable and accurate analytical method is required.…”