Development and validation of an LC-MSMS method for the quantitation of pacritinib; application of kinetics in rabbits.

Accurate and selective LC/ESI-MSMS method development and validation for the quantitation of pacritinib is the primary goal of this study to perform kinetic studies in the healthy rabbit. Chromatographic resolution was accomplished with a hypersil/ODS (50 mm × 4.6 mm, 3 μ) analytical C18 column and a mobile phase composition of 0.1% formic acid and ACN in the proportion of 25:75 with a 0.6 ml/min flow of the mobile phasic system from the analytical column. The method was employed by monitoring the established ionic transitions of m/z-473.25/98.09 for Pacritinib and 506.18/57.12 for the internal standard (Amprenavir) in multiple reaction monitoring. The calibration plot regression line was y = 0.0002× + 0.007, with a correction coefficient (r2) of 0.9989. The CV outcomes for the matrix effect at low-QC and high-QC levels were 4.79% and 4.91%, respectively. The percentage average recoveries for Pacritinib in High-QC (12.70 μg/ml), MQC (8.50 μg/ml), and Low-QC (1.19 μg/ml) were 95.87%, 103.64%, and 94.32%, respectively. The obtained values were found between 2.98 and 5.07% for the QC (1.19, 8.50, and 12.70 μg/ml) samples. The established procedure was subjected to kinetics study of Pacritinib after oral administration in rabbits. Cmax, Tmax, and T1/2, of the Pacritinib tablets were 247.25 ± 3.32 ng/ml, 6.0 ± 0.03 h, and 12.24 ± 0.53 h, respectively. AUC0-∞ infinity for Pacritinib tablets was 1691.74 ± 3.67 ng h/ml. After oral administration of Pacritinib to healthy rabbits, pharmacokinetic characteristics were presented, and the established technique was effectively verified.

Sunkara PK ，Chaganty S ，Ramakrishna K 《-》

Validation of an LC-MS/MS method for quantitation of fostemsavir in plasma.

A novel, sensitive and specific LC-MS/MS technique was developed and validated for the quantification of fostemsavir in human plasma and its pharmacokinetic application in rabbits. Chromatographic separation of the fostemsavir and fosamprenavir (internal standard) were achieved on Zorbax C18 (50 mm × 2 mm × 5 μm) column with 0.80 mL/min flow rate and coupled with API6000 triple quadrupole MS in multi reaction monitoring mode by applying mass transitions m/z 584.16/105.03 for fostemsavir and m/z 586.19/57.07 for the internal standard. The calibration curve exhibited linearity in concentration range of 58.5-2340.0 ng/mL for fostemsavir. The LLOQ was 58.5 ng/mL. The validated LC-MS/MS process was effectively applied for the analysis of plasma in healthy rabbits for determinations of Fostemsavir. From the pharmacokinetic data, the mean of Cmax and Tmax were 198.19 ± 5.85 ng/mL and 2.42 ± 0.13, respectively. Plasma concentration reduced with t1/2 of 7.02 ± 0.14. AUC0→Last value obtained was 2374.87 ± 29.75 ng. h/ml, respectively. In summary, the developed method has been successfully validated and pharmacokinetic parameters were demonstrated after oral administration of Fostemsavir to healthy rabbits.

Lolla S ，Gubbiyappa KS ，Cheruku S ，Bhikshapathi DVRN ... -  《-》

Simultaneous determination of rosuvastatin and fenofibric acid in human plasma by LC-MS/MS with electrospray ionization: assay development, validation and application to a clinical study.

Trivedi RK ，Kallem RR ，Mullangi R ，Srinivas NR ... -  《JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS》

Development and validation of a highly sensitive and robust LC-MS/MS with electrospray ionization method for quantification of rosuvastatin in small volume human plasma samples and its application to a clinical study.

Kallem RR ，Karthik A ，Chakradhar L ，Mullangi R ，Srinivas NR ... -  《arzneimittel-forschung-drug research》

LC-MS/TOF and UHPLC-MS/MS study of in vivo fate of rifamycin isonicotinyl hydrazone formed on oral co-administration of rifampicin and isoniazid.

The formation and fate of 3-formylrifamycin isonicotinyl hydrazone (HYD) was investigated following oral co-administration of rifampicin (RIF) and isoniazid (INH) in Sprague-Dawley (SD) rats (n=5) using advanced analytical modalities. The study was carried out with 20 and 5mg/kg doses of RIF and INH, respectively. The plasma, urine and faeces samples were collected at different time points up to 48h, which were qualitatively and quantitatively evaluated for the presence of HYD after proper sample preparation. For the same, initially liquid chromatography-mass spectrometry/time-of-flight (LC-MS/TOF) method was developed in electrospray ionization (ESI) positive mode, wherein separation was achieved on a C18 column (4.6mmx250mm, 5microm), using a volatile mobile phase in a gradient mode. The presence of HYD was confirmed by accurate mass study, spiking with the standard and UV-visible spectra matching. For quantitative evaluation of HYD, a selective and sensitive ultra high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was developed for all the three matrices. In this case, elution of HYD was achieved on a small C18 column (4.6mmx50mm, 1.8microm) using a short gradient method. The quantitation was done by selective reaction monitoring (SRM) in ESI positive mode. The validation parameters like linearity, accuracy, precision, selectivity, matrix effect, recovery and stability were assessed as per regulatory guidelines. The calibration range was established between 1 and 200ng/ml, with r(2)>0.99 in all the cases. The back calculated values for three quality control (QC) samples, and at lower limit of quantitation (LLOQ) were within 15 and 20%, respectively, of the nominal values. Similarly, the intra- and inter-day precisions were found within 15% at the four tested levels. The HYD was found to be stable for the duration of sample preparation and analysis in the controlled experimental conditions. The analysis of in vivo samples showed a significant extent of HYD in faeces, however, the interaction product was not found in plasma and urine. To verify the results, 5mg/kg oral dose of HYD standard was given to rats separately, and its presence was studied in all the three matrices. Further, in vitro plasma stability of HYD was also carried out to explain its absence in plasma and urine, which showed approximately 55% disappearance of HYD in 2h.

Prasad B ，Singh S 《-》