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.

In silico study and biological screening of benzoquinazolines as potential antimicrobial agents against methicillin-resistant Staphylococcus aureus, carbapenem-resistant Klebsiella pneumoniae, and fluconazole-resistant Candida albicans.

Globally, antibiotic-resistant pathogens have become a serious threat to public health. The use of drugs having structures different from those applied in the clinical treatments of bacterial infections is a well-known potential solution to the antibiotic resistance crisis. Benzo-[g]-quinazolines were identified by our research group as a new class of antimicrobial agents. Herein, to follow-up the research on such compounds, three benzo-[g]-quinazolines (1-3) were studied, as in vitro antibacterial candidates against methicillin-resistant Staphylococcus aureus (MRSA), carbapenem-resistant Klebsiella pneumoniae, and fluconazole-resistant Candida albicans, as well. The minimum inhibitory concentration (MIC) assay for benzoquinazolines was carried out via the calorimetric broth microdilution method using the XTT assay in comparison with vancomycin, ciprofloxacin, and ketoconazole as reference drugs. The target compounds 1-3 revealed high variation in their activity against the examined resistant microbial strains. Benzoquinazoline 3 exhibited a more potent effect against the resistant strains compared with the reference drugs. A docking study was performed to identify the interactions between the benzoquinazolines 1-3 and ligand proteins (OXA-48 carbapenemase, ß-lactamase, and sterol 14-alpha demethylase (CYP51)) at the active sites. Benzoquinazolines 1-3 showed very weak cytotoxicity against human lung fibroblast normal cells (WI-38). The targets showed promising antimicrobial effects against the three resistant strains. These findings may inform future inhibitor discoveries targeting penicillin-binding proteins.

Eco-Friendly UPLC-MS/MS Method for Determination of a Fostamatinib Metabolite, Tamatinib, in Plasma: Pharmacokinetic Application in Rats.

Fostamatinib is a prodrug of the active metabolite tamatinib, which is a spleen tyrosine kinase (Syk) inhibitor used in the treatment of primary chronic adult immune thrombocytopenia and rheumatoid arthritis. A highly sensitive, rapid, reliable, and green method was developed and validated using ultra-performance liquid chromatography and tandem mass spectrometry (UPLC-MS/MS) for quantification of tamatinib in rat plasma. Ibrutinib was used as internal standard and liquid-liquid extraction was applied using tert-butyl methyl ether. The analyte was separated on an AcquityTM CSH C18 (2.1 mm × 100 mm, 1.7 µm) column using mobile phase consisting of 10 mM ammonium acetate and acetonitrile (10:90) and the flow rate was 0.25 mL/min. Electrospray ionization (ESI) was carried out in positive mode. Quantitation of tamatinib and the IS was performed using multiple reaction monitoring mode with precursor-to-product transitions of m/z 471.1 > 122.0 and m/z 441.1 > 84.0, respectively. The calibration range was 0.1-1000.0 ng/mL and the linearity of the method was ≥0.997. The developed method greenness was investigated. All principal parameters for the method, including linearity, accuracy, precision, recovery, and stability, were within acceptable ranges. Tamatinib pharmacokinetic study in rats was successfully carried out using the developed method.

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.

Sustained release and enhanced oral bioavailability of rivaroxaban by PLGA nanoparticles with no food effect.

The purpose of the currents study was to enhance bioavailability of rivaroxaban (RXB) and reduce the food effect. RXB loaded PLGA nanoparticles (RXB-PLGA-NPs) were prepared by emulsion solvent evaporation method and optimized using central composite design (CDD). The optimized RXB-PLGA-NPs (F8) with composition, PLGA (125 mg), PVA (0.5%w/w) and RXB (20 mg) was found optimum with particle size (496 ± 8.5 nm), PDI (0.607), ZP (- 18.41 ± 3.14 mV), %EE (87.9 ± 8.6) and %DL (9.5 ± 1.6). The optimized NPs (F8) was further evaluated in vitro for DSC, FTIR, SEM and in vitro release studies. A comparative pharmacokinetic studies with commercial tablet (XARELTO®) were conducted on fasted and fed state rats. Compared to commercial tablet (XARELTO®), the RXB-PLGA-NPs (F8) exhibited a significant enhancement of bioavailability in both fasted and fed state. In addition, the bioavailability of RXB from NPs (F8) was found unaffected in the presence of food.

A Hydrophilic Interaction Liquid Chromatography-Tandem Mass Spectrometry Quantitative Method for Determination of Baricitinib in Plasma, and Its Application in a Pharmacokinetic Study in Rats.

Baricitinib, is a selective and reversible Janus kinase inhibitor, is commonly used to treat adult patients with moderately to severely active rheumatoid arthritis (RA). A fast, reproducible and sensitive method of liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the quantification of baricitinib in rat plasma has been developed. Irbersartan was used as the internal standard (IS). Baracitinib and IS were extracted from plasma by liquid-liquid extraction using a mixture of n-hexane and dichloromethane (1:1) as extracting agent. Chromatographic separation was performed using Acquity UPLC HILIC BEH 1.7 µm 2.1 × 50 mm column with the mobile phase consisting of 0.1% formic acid in acetonitrile and 20 mM ammonium acetate (pH 3) (97:3). The electrospray ionization in the positive-mode was used for sample ionization in the multiple reaction monitoring mode. Baricitinib and the IS were quantified using precursor-to-production transitions of m/z 372.15 > 251.24 and 429.69 > 207.35 for baricitinib and IS, respectively. The method was validated according to the recent FDA and EMA guidelines for bioanalytical method validation. The lower limit of quantification was 0.2 ng/mL, whereas the intra-day and inter-day accuracies of quality control (QCs) samples were ranged between 85.31% to 89.97% and 87.50% to 88.33%, respectively. Linearity, recovery, precision, and stability parameters were found to be within the acceptable range. The method was applied successfully applied in pilot pharmacokinetic studies.

Validated Reversed-Phase Liquid Chromatographic Method with Gradient Elution for Simultaneous Determination of the Antiviral Agents: Sofosbuvir, Ledipasvir, Daclatasvir, and Simeprevir in Their Dosage Forms.

A simple, rapid, sensitive, and precise reversed-phase liquid chromatographic method was developed and validated for the simultaneous determination of four direct-acting antivirals, sofosbuvir (SF), ledipasvir (LD), declatasvir (DC), and simeprevir (SM), in their respective pharmaceutical formulations. Effective chromatographic separation was achieved on an Agilent Eclipse plus C8 column (250 mm × 4.6 mm, 5 µm) at 40 °C with gradient elution using a mobile phase composed of acetonitrile:phosphate buffer (pH 6.5). The quantification of SF and DC was based on peak area measurements at 260 nm, while the quantification of LD and SM was achieved at 330 nm. The linearity was acceptable from 1.0 to 20.0 µg/mL for the studied drugs, with correlation coefficients >0.999. The analytical performance of the newly proposed HPLC procedure was thoroughly validated according to ICH guidelines in terms of linearity, precision (RSD%, 0.39-1.57), accuracy (98.05-101.90%), specificity, limit of detection (LOD) (0.022-0.039 µg/mL), limit of quantification (LOQ) (0.067-0.118 µg/mL), and robustness. The validated HPLC method was successfully used to analyze the abovementioned drugs in their pure and dosage forms without interference from common excipients present in commercial formulations.

Anacyclus pyrethrum (L): Chemical Composition, Analgesic, Anti-Inflammatory, and Wound Healing Properties.

BACKGROUND: Anacyclus pyrethrum (A. pyrethrum) is a wild species belonging to the family Asteraceae, which is used in traditional medicines. AIM OF THE STUDY: This work was undertaken to study the chemical composition, analgesic, anti-inflammatory, and wound healing properties of hydroalcoholic extracts of different parts (roots, seeds, leaves, and capitula) of A. pyrethrum. Material and Methods: The phytochemical analysis of the studied extracts was conducted by GC-MS. The analgesic activity was evaluated in mice using acetic acid and formaldehyde methods. The anti-inflammatory activity was tested using the inhibitory method of edema induced in rats. The healing activity of the hydroethanolic extracts was explored by excision and incision wound healing models in rats. RESULTS: The phytochemical analysis of the studied plant extracts affirmed the presence of interesting compounds, including some newly detected elements, such as sarcosine, N-(trifluoroacetyl)-butyl ester, levulinic acid, malonic acid, palmitic acid, morphinan-6-One, 4,5.alpha.-epoxy-3-hydroxy-17-methyl, 2,4-undecadiene-8,10-diyne-N-tyramide, and isovaleric acid. The extracts of different parts (roots, seeds, leaves, and capitula) exhibited promising anti-inflammatory, analgesic, and wound healing effects, with percentages of inhibition up to 98%, 94%, and 100%, respectively. CONCLUSION: This study might contribute towards the well-being of society as it provides evidence on the potential analgesic, anti-inflammatory, and wound healing properties of A. pyrethrum.

In-Vivo Antidiabetic Activity and In-Silico Mode of Action of LC/MS-MS Identified Flavonoids in Oleaster Leaves.

BACKGROUND: Olea europea L. subsp. europaea var. sylvestris (Mill) Lehr (Oleaster) is a wild endemic olive tree indigenous to the Mediterranean region. Olea europea leaves represent a natural reservoir of bioactive molecules that can be used for therapeutic purposes. AIM OF THE STUDY: This work was conducted to study antidiabetic and antihyperglycemic activities of flavonoids from oleaster leaves using alloxan-induced diabetic mice. The mode of action of flavonoids against eight receptors that have a high impact on diabetes management and complication was also investigated using molecular docking. RESULTS: During 28 days of mice treatment with doses 25 and 50 mg/kg b.w, the studied flavonoids managed a severe diabetic state (<450 mg/dL), exhibiting a spectacular antidiabetic and antihyperglycemic activity, and improved mice health status compared to diabetic control. The in-silico mode of action of oleaster flavonoids revealed the inhibition of protein tyrosine phosphatase 1B (PTP1B), Dipeptidyl-peptidase 4 (DPP4), α-Amylase (AAM), α-Glucosidase inhibition, Aldose reductase (AldR), Glycogen phosphorylase (GP), and the activation of free fatty acid receptor 1 (FFAR1). CONCLUSION: The findings obtained in the present work indicate that the flavonoids from the oleaster may constitute a safe multi-target remedy to treat diabetes.

Co-stabilization of pioglitazone HCL nanoparticles prepared by planetary ball milling: in-vitro and in-vivo evaluation.

Pioglitazone (PGZ) is an oral antidiabetic agent that increases cell resistance to insulin, thereby decreasing blood glucose levels. PGZ is a class II drug. Because of its pH-dependent solubility, it precipitates at the intestinal pH, resulting in an erratic and incomplete absorption following oral administration, which causes fluctuations in its plasma concentration. A nanoparticle drug delivery system offers a solution to enhance the dissolution rate of this poorly water-soluble drug. PGZ nanoparticles were formulated by the wet milling technique using a planetary ball mill. The effects of the steric stabilizer (Pluronic F-127, PL F-127), electrostatic stabilizer (sodium deoxycholate, SDC), and number of milling cycles were optimized using a Box-Behnken factorial design. The results showed that the ratio of PL F-127: SDC significantly affected the zeta potential and the dissolution efficiency (DE%) of PGZ. The optimized PGZ nanoparticle formulation enhanced the dissolution to reach 100% after 5 min. The in-vivo results showed significant enhancement in Cmax (1.3-fold) compared to that of the raw powder, and both AUC0-24 and AUC0-∞ were significantly (p < 0.05) enhanced. In conclusion, PGZ nanoparticle formulation had enhanced dissolution rate in the alkaline media, which improved its drug bioavailability relative to that of the untreated drug.

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.

Physicochemical, pharmacokinetics, and histological evaluation of new naproxen-quercetin co-lyophilizate to diminish drug-induced gastric irritations in rats.

Quercetin (QUE) is a flavonoid found in several plants and commonly distributed in edible vegetables and fruits. To evaluate the effect of co-lyophilization of naproxen (NPX) with QUE at different weight ratios on physicochemical characteristics induced gastric irritation, and drug pharmacokinetics. NPX binary systems with QUE in different weight ratios were prepared by freeze-drying alkalinized solutions, and were characterized in terms of physicochemical properties as well as NPX dissolution rate in acidic pH. NPX-induced gastric inflammation studies were carried out in rats for 7 days. The pharmacokinetics of the two formulations were assessed to evaluate the bioavailability of NPX-QUE 1:2 co-lyophilizate. Westar rats were administered oral doses equivalent to 40 mg kg-1 of NPX and blood samples were taken from the retro-orbital vein of rats at 0.5, 1.0, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0 12.0, and 24.0 h post dosing. Co-lyophilization of NPX with QUE enhanced drug dissolution rate in the acidic medium, which was correlated with an increased QUE weight ratio in the co-lyophilizates. Rat stomachs from group V (NPX-QUE 1:2 co-lyophilizate) showed non-significant changes, and biopsies from this group showed no significant leukocyte infiltration and edema in the mucosa. The bioavailability of NPX-QUE 1: 2 co-lyophilizate was similar to the control sample. NPX-QUE 1: 2 co-lyophilizate could be an alternative to NPX in the treatment of arthritis as it minimizes the potential for gastric irritation and enhances safety while retaining the same efficacy and bioavailability.

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.

Determination of (4-(1,3-dioxo-1,3-dihydro-2H-isoindol- 2-yl)-N'-[(4-ethoxyphenyl) methylidene] benzohydrazide, a novel anti-inflammatory agent, in biological fluids by UPLC-MS/MS: Assay development, validation and in vitro metabolic stability study.

A thalidomide analog, (4-(1,3-dioxo-1,3-dihydro-2H-isoindol-2-yl)-N'-[(4-ethoxyphenyl) methylidene] benzohydrazide), has been identified as a promising broad-spectrum anti-inflammatory agent in previous study. In this study, a sensitive and selective UPLC-MS/MS assay was developed and validated for its determination in rat plasma samples. The chromatographic separation was performed on an Aquity BEH C18 column using mobile phase comprising of acetonitrile and 10 mm ammonium acetate in the ratio of 85: 15, at flow rate of 0.3 mL/min. The detection and quantification were performed in positive multiple reaction monitoring mode by parent to daughter ion transition of 414.06 ˃ 148.05 for analyte and 411.18 ˃ 191.07 for internal standard (risperidone), respectively using electrospray ionization source. The sample extraction process consisted of liquid-liquid extraction method using diethyl ether as the extracting solvent. The assay was validated by following FDA guidelines and all parameters were found to be within acceptable limits. The linearity was between 10.1 and 2500 ng/mL and the lower limit of quantification was 10.1 ng/mL. The reported results indicate that the assay could meet the requirement for analysis of this compound in amounts expected to the present in actual samples. Further, in vitro metabolic stability study was performed in rat liver microsomes by using the validated assay.

Docking and antiherpetic activity of 2-aminobenzo[de]-isoquinoline-1,3-diones.

As part of our search for new compounds having antiviral effects, the prepared 2-aminonaphthalimide series was examined for its activity against the herpes simplex viruses HSV-1 and HSV-2. This represents the first study of the antiviral effects of this class of compounds. The new series of 2-amino-1H-benzo[de]isoquinoline-1,3-diones was examined against HSV-1 and HSV-2 using a cytopathic effect inhibition assay. In terms of effective concentration (EC50), furaldehyde, thiophene aldehyde and allyl isothiocyanide derivatives 14‒16 showed potent activity against HSV-1 (EC50 = 19.6, 16.2 and 17.8 µg/mL), compared to acyclovir as a reference drug (EC50 = 1.8 µg/mL). Moreover, 14 and 15 were found to exhibit valuable activity against HSV-2. Many of the tested compounds demonstrated weak to moderate EC50 values relative to their inactive parent compound (2-amino-1H-benzo[de]isoquinoline-1,3-dione), while compounds 7, 9, 13, 14, 15, 16, 21 and 22 were the most active set of antiviral compounds throughout this study. The cytotoxicity (CC50), EC50, and the selectivity index (SI) values were determined. In a molecular docking study, the ligand-receptor interactions of compounds 1-24 and their parent with the HSV-1 thymidine kinase active site were investigated using the Molegro Virtual Docker (MVD) software. Based on the potent anti-HSV properties of the previous naphthalimide condensate products, further exploration of this series of 2-amino-1H-benzo[de]isoquinoline-1,3-diones is warranted.

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.

An Ultraperformance Liquid Chromatography Tandem-Mass Spectrometry Method for Determination of Multiclass Pharmaceuticals in Water Sample by Dispersive Liquid-Liquid Microextraction Combined with Ultrasound Assisted Reverse Extraction from Solidified Floating Organic Droplets.

A novel, simple, and reliable ultraperformance liquid chromatography tandem-mass spectrometry (UPLC-MS/MS ) assay based on dispersive liquid-liquid microextraction followed by ultrasound-assisted reverse extraction from solidified floating organic droplets was established for determination of multiclass pharmaceuticals in the water sample. Six commonly used drugs of various therapeutic classes: ibuprofen, ketorolac, lamotrigine, propranolol, pantoprazole, and losartan were extracted from water samples by using 50 µL 1-undecanol as extracting solvent and 400 µL acetonitrile as dispersive solvent. After collecting the floating organic droplets by cold centrifugation, an ultrasound-assisted back extraction procedure was performed to make the sample compatible for UPLC-MS/MS analysis. Acquity BEH C18 column (2.1 × 100; 1.7 µm) was used for separation of target analytes that were eluted by a gradient mobile phase composition of 15 mM ammonium acetate and acetonitrile at a flow rate of 0.25 mL/min. The sample ionization was performed by using electrospray ionization in positive mode, and multiple reaction monitoring was used for quantification of target analytes. After optimizing the assay conditions, all calibration curves were found to be linear with limit of detection and limit of quantification were ranged in between 0.06-0.15 and 0.16-0.41 ng/mL, respectively. The enrichment factor was found to be 172-192-fold and the relative recovery was ranged between 93.1 and 109.4% between target analytes. These satisfactory results confirmed that the proposed method is specific and reliable for application of trace analysis of target analytes in waste water samples.

A simple and sensitive HILIC-based UHPLC-MS/MS method for quantifying of rivaroxaban in dried blood spots: Application in comparison with the plasma sample method.

Rivaroxaban, indicated for the treatment of atrial fibrillation, deep vein thrombosis, pulmonary embolism, and coronary or peripheral artery disease, is one of the most frequently used direct oral anticoagulants. Therapeutic drug monitoring [TDM] is essential to minimize bleeding and thrombosis during personalized rivaroxaban treatment. An efficient and reliable analytical technique is required to quatify the rivaroxaban during its therapeutic indication. Dried blood spots (DBSs) sampling is a convenient bioanalytical method with minimal invasive blood drawing, long-term stability, and low shipment and storage costs. Therfore, DBS sampling technique is growing rapidly for TDM of drugs in medical care. This study developed an ultra high performance liquid chromatography-tandem mass spectrometry method of quantitating rivaroxaban in DBSs samples using the isotopic labeled analog (rivaroxaban-d4) as an internal standard (IS). Rivaroxaban and IS were separated on an Acquity HILIC column and eluted with a mobile-phase composition of acetonitrile and 20 mM ammonium acetate in the ratio of 95:5 at a flow rate of 0.3 mL/min. The precursor-to-product ion transitions of 436.03 ˃ 144.9 for rivaroxaban and 440.04 ˃ 144.9 for IS were used to quantify in multiple reaction monitoring mode. The method was accurate and precise in the 2.06-1000 ng/mL calibration range without hematocrit and blood spot volume effects. Rivaroxaban was stable in DBSs samples under different anticipated storage and temperature conditions. We observed good correlation between the plasma concentration and the DBSs concentration, indicating that the proposed DBSs method is suitable for monitoring the rivaroxaban concentration using a simple and convenient sample collection procedure.

Improving the Solubilization and Bioavailability of Arbidol Hydrochloride by the Preparation of Binary and Ternary ß-Cyclodextrin Complexes with Poloxamer 188.

In the current study, the effect of poloxamer 188 on the complexation efficiency and dissolution of arbidol hydrochloride (ADL), a broad-spectrum antiviral agent, with ß-cyclodextrin (ß-CD) was investigated. Phase solubility studies confirmed a stoichiometry of a 1:1 ratio for both ADL:ß-CD and ADL/ß-CD with a 1% poloxamer 188 system with an AL type of phase solubility curve. The stability constants (K1:1) calculated from the AL type diagram were 550 M-1 and 2134 M-1 for AD:ß-CD and ADL/ß-CD with 1% poloxamer 188, respectively. The binary ADL/ß-CD and ternary ADL/ß-CD with 1% poloxamer 188 complexes were prepared by kneading and a solvent evaporation method and were characterized by aqueous solubility, FTIR, PXRD, DSC and SEM in vitro studies. The solubility (13.1 fold) and release of ADL were markedly improved in kneaded ternary ADL/ß-CD with 1% poloxamer 188 (KDB). The binding affinity of ADL and ß-CD was confirmed by 1H NMR and 2D ROSEY studies. The ternary complex (KDB) was further subjected for in vivo pharmacokinetic studies in rats and a significant improvement in the bioavailability (2.17 fold) was observed in comparison with pure ADL. Therefore, it can be concluded that the solubilization and bioavailability of ADL can be remarkably increased by ADL/ß-CD complexation in the presence of a third component, poloxamer 188.

Anacyclus pyrethrum var. pyrethrum (L.) and Anacyclus pyrethrum var. depressus (Ball) Maire: Correlation between Total Phenolic and Flavonoid Contents with Antioxidant and Antimicrobial Activities of Chemically Characterized Extracts.

In this work, two varieties of Anacyclus pyrethrum (L.) including Anacyclus pyrethrum var. pyrethrum (L.) and Anacyclus pyrethrum var. depressus (Ball) Maire were evaluated for their mineral and chemical compositions, total phenolic and flavonoid contents, and antimicrobial and antioxidant activities using hydroalcoholic extracts from their different parts (leaves, capitula, roots, and seeds). The phytochemical and mineral compositions were carried out using standard methods. The antioxidant activity was determined using the DPPH (2,2-diphenyl-1-picrylhydrazyl), ABTS (2,2-azino-bis 3-ethylbenzothiazolin-6-sulfonic acid), and FRAP (ferric reducing antioxidant power) tests. The antimicrobial activity was assayed using the agar diffusion, minimum inhibitory concentration, and minimum bactericidal concentration methods. The results of the chemical analysis showed that both varieties contained interesting mineral and chemical compositions with potentially active compounds; among them, N-isobutyl-2,4-heptadiene-6-monoynamide and cinnamic acid were detected in the Anacyclus pyrethrum var. pyrethrum (L.) only while thiadiazolo [5,4-d] pyrimidin-7-amine and N-isobutyl-2,4-undecadiene-8,10-diynamide compounds were limited to the Anacyclus pyrethrum var. depressus (Ball) Maire. In vitro antioxidant and antimicrobial activities of the two varieties demonstrated that the different parts had prominent antioxidant and antimicrobial properties. The principal component analysis (PCA) showed great similarity in the activity of the leaves, capitula, and seeds of both plants and a high difference in roots. Anacyclus pyrethrum var. pyrethrum roots were characterized by a high content in phenols and flavonoids and better antibacterial activities compared to Anacyclus pyrethrum var. depressus (Ball) Maire roots, which were characterized by better antioxidant activities. From this study, it can be concluded that the two varieties of Anacyclus pyrethrum (L.) showed promising mineral and chemical compositions with antioxidant and antimicrobial properties.