Eco-Friendly, Simple, Fast, and Sensitive UPLC-MS/MS Method for Determination of Pexidartinib in Plasma and Its Application to Metabolic Stability.

Pexidartinib is the first drug approved by the U.S. Food and Drug Administration specifically to treat the rare joint tumor tenosynovial giant cell tumor. In the current study, a validated, selective, and sensitive UPLC-MS/MS assay was developed for the quantitative determination of pexidartinib in plasma samples using gifitinib as an internal standard (IS). Pexidartinib and IS were extracted by liquid-liquid extraction using methyl tert-butyl ether and separated on an acquity BEH C18 column kept at 40 °C using a mobile phase of 0.1% formic acid in acetonitrile: 0.1% formic acid in de-ionized water (70:30). The flow rate was 0.25 mL/min. Multiple reaction monitoring (MRM) was operated in electrospray (ESI)-positive mode at the ion transition of 418.06 > 165.0 for the analyte and 447.09 > 128.0 for the IS. FDA guidance for bioanalytical method validation was followed in method validation. The linearity of the established UPLC-MS/MS assay ranged from 0.5 to 1000 ng/mL with r > 0.999 with a limit of quantitation of 0.5 ng/mL. Moreover, the metabolic stability of pexidartinib in liver microsomes was estimated.

Caralluma europaea (Guss.) N.E.Br.: Anti-Inflammatory, Antifungal, and Antibacterial Activities against Nosocomial Antibiotic-Resistant Microbes of Chemically Characterized Fractions.

Caralluma europaea (Guss.) N.E.Br.: (C. europaea) is a wild medicinal plant belonging to the family Apocynaceae. It is commonly used in traditional medicines for treating several diseases. The present work aims to evaluate the anti-inflammatory, antibacterial, and antifungal potentials of C. europaea fractions including hydro ethanol (ET CE), n-butanol (But CE), and polyphenol (Poly CE). The chemical composition of hydroethanol, n-butanol, and polyphenol-rich fractions from C. europaea were determined using GC-MS after silylation. The anti-inflammatory effect of hydroethanol, n-butanol, and polyphenol-rich fractions was studied by carrageenan-induced paw edema. Antibacterial and antifungal activities of hydroethanol, n-butanol, and polyphenol-rich fractions against Gram-positive bacteria, Gram-negative bacteria, and yeasts were assessed using the disc diffusion and micro-dilution assays. The findings of the chemical characterization affirmed the presence of interesting bioactive compounds in C. europaea fractions. The polyphenol-rich fraction was the best inhibitor of edema by75.68% after 6 h of treatment. The hydroethanol fraction was the most active against both bacteria and yeasts. This study contributes to society as it provides potential bioactive compounds in C. europaea extract, which may help in fighting nosocomial antibiotic-resistant microbes.

Brassica juncea L. (Mustard) Extract Silver NanoParticles and Knocking off Oxidative Stress, ProInflammatory Cytokine and Reverse DNA Genotoxicity.

Detoxification is one of the main vital tasks performed by the liver. The purpose of this study was to investigate whether mustard in its normal or nanoparticles could confer a protective/therapeutic effect against TAA-induced acute liver failure in experimental animal models. Mustard ethanolic extract was analyzed by HPLC/MS. To induce liver failure, male rats were injected with 350 mg/kg bw TAA IP, then treated orally with a dose of 100 mg/kg for 15 d of mustard extract and its nanoform before and following induction. The levels of serum liver functions, total cholesterol (TCHo), total glyceride (TG), total bilirubin (TBIL), hepatic malonaldhyde (MDA) and nitric oxide (NO),glutathione (GSH), sodium oxide dismutase (SOD), as well as tumor necrosis factor (TNF-α,) and interleukin 6 (IL-6), were estimated. DNA genotoxicity and hepatic pathology, and immunohistologic (IHC) changes were assayed. The antioxidant content of Phenolic acids, flavonoids in mustard ethanolic extract substantially decreased the levels of ALT, AST, ALP and rehabilitated the histopathological alterations. In addition, nanoforms of mustard ethanol extract have notably increased the levels of GSH, SOD and significantly reduced the levels of MDA. The expression levels of TNF-α and IL-6 in serum and tissue were markedly downregulated. DNA genotoxicity was significantly reversed. Mustard introduced a protective and medicinal effect against TAA in both its forms.

UPLC-MS/MS assay for quantification of an inhibitor of kinases (Foretinib) in plasma: Application to a pharmacokinetic study in rats.

Foretinib, an oral multikinase inhibitor, is known to have anti-tumor effects against cancers. The doses and the levels of foretinib vary based on the type of cancer to be treated. An accurate and precise method is required to determine the level of foretinib and its pharmacokinetics. Here, we developed such a method, which was validated based on the guidelines of the FDA and EMA. Foretinib and ibrutinib (the internal standard (IS)) were extracted using tert-butyl methyl ether. Foretinib and IS were eluted in approximately 1.2 min. Thus, a linear, fast, accurate, and precise method was developed. The calibration curve was linear (r2 ˃ 0.997) in the range of 0.5-400.0 ng/mL and the lowest limit of quantitation was 0.5 ng/mL. The average recovery, accuracy, and precision were 87.9%, 88.7%, and ≤7.8%, respectively. The analyte was deemed stable using various stability tests. The validated assay was then fruitfully applied to a pharmacokinetics study in rats, which revealed that foretinib was absorbed and the maximum concentration achieved at 4.0 h after the administration of a single dose of foretinib.

A rapid, simple and highly sensitive UPLC-MS/MS method for quantitation of pimavanserin in plasma and tissues: Application to pharmacokinetics and brain uptake studies in mice.

Pimavanserin is a new drug approved by the FDA for Parkinson's disease psychosis and other neurological disorders such as Alzheimer's disease. In this study, we developed a UPLC-MS/MS method to quantify pimavanserin disposition in the brain and its pharmacokinetics in mice. Vilazodone was used as the internal standard. Pimavanserin and IS were extracted by liquid-liquid extraction using tert-butyl methyl ether and separated using an Acquity UPLC BEH™ C18 column. The mobile phase consisted of solvent A (0.1% formic acid in acetonitrile) and B (0.1% formic acid in 20 mM ammonium acetate buffer) (A: B, 70:30 v/v) at a flow rate of 0.25 ml/min. The multiple reaction monitoring transitions were performed at m/z 428.23 â†’ 98.15 for pimavanserin and m/z 441.70 > 155.03 for the IS. The developed method was found to be sensitive, fast, and reproducible. The linearity of the method was ˃0.99 over the range of 0.1-300 ng/mL in plasma and 0.25-300 ng/g in the brain homogenate. Precision and accuracy were within the acceptance range. The method was applied to pharmacokinetics and brain uptake studies, which showed that pimavanserin penetrates the blood-brain barrier and reaches a Cmax of 21.9 ± 6.66 ng/g in 2.0 h. We also found that pimavanserin brain to plasma ratio (Kbrain/plasma) is 0.16 ± 0.05 and it is rapidly eliminated.

Ultra-performance hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry for simultaneous determination of allopurinol, oxypurinol and lesinurad in rat plasma: Application to pharmacokinetic study in rats.

A fixed dose combination of lesinurad and allopurinol has been recently approved by USFDA and EMA for treatment of gout-associated hyperuricemia in patients who have not achieved target serum uric acid levels with allopurinol alone. In this study, an ultra-performance hydrophilic interaction liquid chromatography (UPHILIC) coupled with tandem mass spectrometry method was developed and validated for simultaneous determination of allopurinol, oxypurinol and lesinurad in rat plasma. Liquid liquid extraction using ethyl acetate as extracting agent was used for samples extraction procedure. Acquity UPLC HILIC column (100 mm x 2.1, 1.7µm) was used for separation of allopurinol, oxypurinol, lesinurad and internal standard (5-Florouracil). The mobile phase consisting of acetonitrile, water and formic acid (95:5:0.1, v/v/v), were eluted at 0.3 mL/min flow rate having total chromatographic run time of 3 min per sample. The analytes were detected on Acquity triple quadrupole mass spectrometer equipped with a Z-Spray electrospray ionization (ESI). The ESI source was operated in negative mode and multiple reaction monitoring was used for ion transition for all compounds. The precursor to product ion transition of m/z 134.94 > 64.07 for allopurinol, 150.89 > 41.91 for oxypurinol, 401.90 > 176.79 for lesinurad and 128.85 >41.92 for internal standard were used for identification and quantification. The calibration curves for all analytes were found to be linear with weighing factor of 1/x2 using regression analysis. The developed assay was successfully applied in an oral pharmacokinetic study of allopurinol, oxypurinol and lesinurad in rats.

Development and validation of a UPLC-MS/MS method for determination of motesanib in plasma: Application to metabolic stability and pharmacokinetic studies in rats.

Motesanib is a potent angiokinase inhibitor, has shown potential therapeutic effects against various cancers. An accurate, reproducible, rapid, specific, sensitive, and valid ultraperformance liquid chromatography-tandem mass spectrometry method was established to quantify motesanib in rat plasma. Motesanib and linifanib (used as an internal standard; IS) were extracted from plasma by liquid-liquid extraction using tert-butyl methyl ether as extracting agent. Chromatographic separation was performed on Acquity™ UPLC BEH™ C18 column (100 mm × 2.1 mm i.d., 1.7 µm; Waters Corp., USA) using a mobile phase comprising of 0.1% formic acid acetonitrile: ammonium acetate (90:10 v/v) eluted at a flow rate of 0.25 mL/min. The electrospray ionization in the positive-mode was used for sample ionization. In the multiple reaction monitoring mode, motesanib and the IS were quantified using precursor-to-product ion transitions of m/z 374.03 → 212.02 and m/z 376.05 → 251.05, respectively. The ranges of the calibration curves were 5.0-1000.0 ng/mL with coefficient of determination of ≥0.998. The method was validated by following recently implemented USFDA guideline for bioanalytical method validation. The lower limit of quantification was 5.0 ng/mL, whereas the intra-day and inter-day accuracies of quality controls (QCs) samples were ranged between 88.91% to 95.65% and 90.20% to 102.17%, respectively. In addition, the linearity, recovery, precision, and stability parameters were found to be within the acceptable range. The method was applied successfully to in vitro microsomal metabolic stability and preliminary oral pharmacokinetic studies in rats. The applied UPLC/MS/MS method was found to be adequately sensitive and therefore suitable for application in routine motesanib pharmacokinetic studies.

UPLC/MS-MS assay development for estimation of mozavaptan in plasma and its pharmacokinetic study in rats.

AIM: Mozavaptan is a nonpeptide vasopressin receptor antagonist approved for the treatment of ectopic antidiuretic hormone secretion syndrome. METHODS & RESULTS: A simple, rapid and fully validated UPLC/MS-MS method was developed for the quantitation of mozavaptan in rat plasma. The chromatographic separation was conducted on an Acquity UPLC BEH™ C18 column with an optimum mobile phase of 10 mM ammonium acetate buffer and 0.1% formic acid in acetonitrile (30:70 v/v) at a flow rate of 0.3 ml/min. The multiple reaction monitoring transitions were performed at m/z 428.16→119.03 for mozavaptan and m/z 237.06→179.10 for carbamazepine (internal standard). CONCLUSION: The method was effectively applied for the determination of mozavaptan pharmacokinetic parameters after the oral administration of 3 mg/kg mozavaptan in rats.

A validated UPLC-MS/MS method for flibanserin in plasma and its pharmacokinetic interaction with bosentan in rats.

AIM: The purpose of this study was development, validation and application of ultra-performance liquid chromatography (UPLC)-ESI-MS/MS method for quantitation of flibanserin in plasma samples. METHOD & RESULTS: After extraction of analyte from plasma by diethyl ether, separation was performed on UPLC C18 column using mobile phase composition of 10 mM ammonium formate-acetonitrile (30:70, v/v) by isocratic elution of 0.3 ml/min. The multiple reaction monitoring transitions of m/z 391.13 → 161.04 and 384.20 → 253.06 were used for detection of analyte and internal standard (quetiapine), respectively. The calibration curves were linear (r ≥ 0.995) between 0.22 and 555 ng/ml concentration and all validation results were within the acceptable range as per US FDA guidelines. CONCLUSION: The assay procedure was fully validated and successfully applied in pharmacokinetic interaction study of flibanserin with bosentan in rats.

Method development for quantification of quizartinib in rat plasma by liquid chromatography/tandem mass spectrometry for pharmacokinetic application.

Quizartinib is a highly potent inhibitor of the fms-like tyrosine kinase receptor, which is one of the most commonly mutated genes in acute myeloid leukemia. Quizartinib has shown a significant antileukemic clinical influence among relapsed/refractory acute myeloid leukemia patients. This study aimed at developing and validating an analytical method for the measurement of quizartinib in rat plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method was validated according to US Food and Drug Administration guidelines, and the results obtained in this work met the set criteria. Liquid-liquid extraction was used and chromatographic separation was achieved on a BEHTM C18 column. Detection of quizartinib was achieved in multiple reaction monitoring mode using positive-ion mode electrospray ionization. The MS/MS ion transitions at mass-to-charge ratios (m/z) of 561.129/114.09 and 441.16/84.03 were monitored for quizartinib and ibrutinib, respectively. The linear detection range was 2-1000 ng/mL (r > 0.998), with intra- and inter-day assay precisions ≤13.07 and 13.17%, respectively. This rapid, simple and sensitive method was validated and successfully applied to the pharmacokinetic study of quizartinib in rat samples.

Bioavailability enhancement and pharmacokinetic profile of an anticancer drug ibrutinib by self-nanoemulsifying drug delivery system.

OBJECTIVE: The current studies were undertaken to enhance dissolution and bioavailability/pharmacokinetic profile of a newly approved anticancer drug ibrutinib (IBR) via encapsulation of drug into self-nanoemulsifying drug delivery system (SNEDDS). METHODS: Various SNEDDS formulations of IBR were developed by aqueous phase titration method using Capryol-PGMC (oil phase), Tween-20 (surfactant), Carbitol (cosurfactant) and water (aqueous phase). Developed SNEDDS of IBR was evaluated in vitro for various physicochemical properties and drug release profile. KEY FINDINGS: Based on lowest droplet size (28.7 ± 3.2 nm), least polydispersity (0.123), optimal values of zeta potential (-32.8 mV) and refractive index (1.336), highest % transmittance (98.7 ± 0.2%), highest drug release profile via dialysis membrane (98.9 ± 8.2% after 48 h) and the presence of lowest concentration of Capryol-PGMC (12% w/w), SNEDDS I1 was selected for in-vivo pharmacokinetic/bioavailability studies in female Wistar rats. In-vivo pharmacokinetic studies in rats showed that optimized SNEDDS I1 controlled the absorption of IBR compared with IBR suspension. The bioavailability of IBR from optimized SNEDDS I1 was enhanced around 2.64 times in comparison with IBR suspension. CONCLUSION: These results indicated the potential of developed SNEDDS as an alternative drug delivery system for IBR to enhance its bioavailability and anticancer efficacy.

Androgen receptor antagonists and anti-prostate cancer activities of some synthesized steroidal candidates.

In continuation of our previous work, a novel series of steroid derivatives were synthesized and their androgen receptor (AR) antagonist activities and in vivo antiandrogenic properties were evaluated. Twenty-one heterocyclic derivatives containing a cyanopyrane ring fused to a steroidal moiety were conveniently synthesized and screened for their antagonistic, antiandrogen and prostate anticancer activities comparable to that of bicalutamide as the reference control. Some of the compounds exhibited better antagonistic, antiandrogen and prostate anticancer activities than the reference controls. Initially the acute toxicity of the compounds was assayed via the determination of their LD(50). Synthetic steroidal structures fused to a substituted cyanopyrane ring seem to be a promising approach in the search for novel leads for potent antagonistic, antiandrogen and prostate anticancer agents.