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In this research work, an isocratic, reversed-phase high-performance liquid chromatography-ultraviolet/visible detector method was developed for analysis of voriconazole standard (stock-solution) and in plasma samples. Optimization and validation of the method was carried out as per international guidelines. The method offered a simple liquid–liquid extraction technique, which exhibited best recovery of voriconazole along with fluconazole, i.e., internal standard. Different experimental conditions were tried and ultimately, the best outcomes were accomplished utilizing C-18 Perkin-Elmer® column with particulars of 150 mm length, 4.6 mm inner diameter and 5 μm particle size, protected by an RP-18 Perkin-Elmer® Pre-column guard cartridge with specifications of 10 μm particle size, 30 mm length and 4.6 mm inner diameter, utilizing mobile-phase of acetonitrile-water (ACN: H2O) in proportion of 60: 40 v/v, having a flow rate of 1.5 mL/min, and wavelength of 254 nm. All the analytes were observed to be separated in ≤7 min. A linear calibration curve was obtained at concentration range of 01–10 μg/mL of voriconazole. The correlation coefficient of voriconazole was observed to be 0.999, and average recovery (in percent) was 97.4%, whereas the relative standard deviation value was ≤2%. The lower limit of detection was 0.01 μg/mL, whereas, lower limit of quantification was 0.03 μg/mL, respectively. This developed method provided outstanding results of all validation parameters, i.e., recovery, accuracy, selectivity, precision and reproducibility. The method proposed for voriconazole analysis was applied effectively for further research investigation of voriconazole in human-plasma samples (to assess the pharmacokinetic parameters), pharmaceutical formulations and pharmacokinetic drug–drug interaction’s.

Exploring new antimicrobial and cytotoxic drugs has been one of the most active areas of research.

In current study, the pharmacokinetics (PK) of rosuvastatin were evaluated in Pakistani healthy volunteers and compared with those reported in other population. This was a randomized and open labeled clinical trial in which a single oral dose of 40 mg rosuvastatin was administered to the overnight fasted healthy volunteers. Plasma concentrations of rosuvastatin were quantified by a validated liquid chromatography-tandem mass spectrometry method. The PK parameters of rosuvastatin and its metabolite N-desmethyl-rosuvastatin were determined by PK specific software i.e., PK-Summit® (PK-Solutions). A total of 20 healthy volunteers having BMI in the normal ranges were included in this study. All PK parameters were represented as mean ± SD and 95% confidence intervals of the means have been calculated. The Cmax (29.07 ± 6.88 ng/mL), [AUC]

Resistance to antimicrobial agents are rendering therapies ineffective around the globe, leading to increased mortality and treatment cost. Likewise, non-steroidal anti-inflammatory drugs (NSAIDs) and analgesics possess several side effects particularly peptic ulcer and gastrointestinal problems. Metallic nanoparticles significantly enhances the therapeutic efficacy of natural extracts owing to improved bioavailability thereby lowering the dose and side effects. The purpose of this research was to investigate the efficacy of gold nanoparticles (AuNPs). In this study, Sambucus wightiana whole plant aqueous extract was used for rapid and eco-friendly synthesis of AuNPs. They were characterized by various analytical techniques including UV–Visible spectroscopy (UV–Vis), transmission and scanning electron microscopy (TEM and SEM), energy dispersive X-ray spectroscopy (EDX), Zetasizer, X-ray diffractometer (XRD) and Fourier transform infra-red spectroscopy (FTIR). The UV–Vis spectra revealed a distinct absorption peak at 539 nm; TEM and SEM images confirmed the formation of heterogeneously dispersed AuNPs with an average area of 152.77 nm2 and width of 15.96 nm. The AuNPs showed significant inhibitory zones against Escherichia coli (25 mm), Staphylococcus epidermis (23 mm) and Salmonella enteritidis (18 mm) with MIC values 0.13, 0.11 and 0.16 mg/ml, respectively. Among fungal strains it showed highest percent inhibition against Fusarium solani (90%) and Microsporum canis (80%) with MIC values 0.02 and 0.01 mg/ml, respectively. It showed maximum anti-inflammatory activity (43.70, 48.80 and 57.08%) at 20 mg/kg dose at both early and late hours of inflammation. Likewise, in vitro models depicted concentration dependent inhibition of 5-LOX and COX-2 enzymes. AuNPs showed highest antioxidant activity (68.7% inhibition) at 1000 µg/ml, compared to ascorbic acid that showed 77.8% inhibition at the same concentration. Similarly, it exhibited significant (P ≤ 0.001) dose dependent analgesic effect with maximum inhibition (56.22%) at 20 mg/kg. In conclusion, the above findings suggest that AuNPs should be studied further in order to develop safe and effective formulations.

BACKGROUND Chronic kidney disease (CKD)-associated pruritus (CKD-aP) contributes to poor quality of life, including reduced sleep quality and poor sleep quality is a source of patient stress and is linked to lower health-related quality of life. This study aimed to investigate the effectiveness of zolpidem 10 mg and acupressure therapy on foot acupoints to improve the sleep quality and overall quality of life among hemodialysis patients suffering from CKD-aP. METHOD A multicenter, prospective, randomized, parallel-design, open label interventional study to estimate the effectiveness of zolpidem (10 mg) oral tablets versus acupressure on sleep quality and quality of life in patients with CKD-aP on hemodialysis. A total of 58 hemodialysis patients having sleep disturbance due to CKD-aP completed the entire 8-week follow-up. The patients were divided into a control (acupressure) group of 28 patients and an intervention (zolpidem) group of 30 patients. RESULTS A total of 58 patients having CKD-aP and sleep disturbance were recruited. In the control group there was a reduction in the PSQI score with a mean ± SD from 12.28 ± 3.59 to 9.25 ± 3.99, while in the intervention group the reduction in PSQI score with a mean ± SD was from 14.73 ± 4.14 to 10.03 ± 4.04 from baseline to endpoint. However, the EQ5D index score and EQ-visual analogue scale (VAS) at baseline for the control group with a mean ± SD was 0.49 ± 0.30 and 50.17 ± 8.65, respectively, while for the intervention group the values were 0.62 ± 0.26 and 47.17 ± 5.82, respectively. The mean EQ5D index score in the control group improved from 0.49 ± 0.30 to 0.53 ± 0.30, but in the intervention group there was no statistical improvement in mean EQ5D index score from 0.62 ± 0.26 to 0.62 ± 0.27 from baseline to week 8. The EQ 5D improved in both groups and the EQ-VAS score was 2.67 points higher at week 8 as compared to baseline in the control group, while in the intervention group the score was 3.33 points higher at week 8 as compared to baseline. Comparing with baseline, the PSQI scores were significantly reduced after week 4 and week 8 (P =

Liqui-solid technique and solid dispersion formation are two novel approaches for enhancement of dissolution rate of BCS class II drugs. Liqui-solid compact converts a liquid drug or drug solution into a free flowing powder with enhanced dissolution rate. In case of solid dispersion drug is molecularly dispersed in a hydrophilic polymer in solid state. In the present study, Liqui-solid and solid dispersion techniques were applied to enhance the dissolution of the Hydrochlorothiazide. Three formulations of Hydrochlorothiazide were prepared by liqui-solid technique using micro crystalline cellulose as carrier material and colloidal silicon dioxide as coating material. Water, poly ethylene glycol-400 and Tween-60 were used as solvent system. Solid dispersions of Hydrochlorothiazide were prepared by solvent fusion method using PEG-4000 as carrier polymer. Tablets were subjected to evaluation of various physical and chemical characteristics. Dissolution profiles of tablets prepared by the novel techniques were compared with marketed conventional tablets. Model independent techniques including similarity factor, dissimilarity factor and dissolution efficiency were applied for comparison of dissolution profiles. The results obtained indicated that liqui-solid compact formulations were more effective in enhancing the dissolution rate compared with solid dispersion technique. The liqui-solid compacts improved the dissolution rate up to 95% while the solid dispersion increased it to 88%.

This study was designed to evaluate a comparative single dose (40mg) pharmacokinetics (PK) of Omeprazole (OMP) and its two metabolites, 5-hydroxy Omeprazole (5-OH-OMP) and Omeprazole sulphone (OMP-S) in poor (PM) and extensive (EM) metabolizer Pakistani healthy adult volunteers. The frequency of CYP2C19 and CYP3A4 varies widely in different populations. The present study was conducted to evaluate the PK of OMP and its two metabolites in Pakistani population and to review different studies conducted after administration of single dose of OMP. Twenty two subjects were enrolled in this study and divided into two groups. The CYP2C19 phenotyping was evaluated by the metabolic ratio of OMP to 5-OH-OMP. It was a single dose, open label study and the blood samples from subjects were collected at different time intervals until 24 hours. The PK parameters were calculated using the PK-summit software. The metabolic ratio of area under the plasma concentration-time curve AUCOMP/5-OH-OMP was 1.86 ± 0.572 and13.84 ± 2.504 for EM and PM, respectively; maximum plasma concentration (C

A novel liquid chromatography–tandem mass spectrometry (LC–MS/MS) method was developed for the determination of rosuvastatin (rosuva) and its metabolite N-desmethyl rosuvastatin (NDM-rosuva) in human plasma using atorvastatin as internal standard. The method was validated according to international guidelines. The analytical column used was HiChrom® C18 (150 × 3.0 mm, 3 µm; Reading, UK) and the mobile phase comprised of 0.1% formic acid in acetonitrile and 0.1% formic acid in water (70:30 v/v), pumped at 300 µL/min. The precipitation of plasma proteins and extraction of analytes were carried out by a simple one-step procedure using acetonitrile. The calibration curves were linear (r2 = 0.999) over the concentration range of 0.2–20 ng/mL for rosuva and 0.1–10 ng/mL for NDM-rosuva. The lower limits of detection and quantification for rosuva were 0.1 and 0.2 ng/mL, whereas for NDM-rosuva, these were 0.03 and 0.1 ng/mL, respectively. The intra- and inter-day precisions expressed as relative standard deviation...

A method was developed for the determination of omeprazole, 5-hydroxy-omeprazole, and omeprazole-sulphone in human plasma. The mobile phase with 0.1% formic acid in acetonitrile and 0.1% formic acid in water (40/60 v/v) was used successfully for the first time for the analysis of these analytes. Analysis was carried out using Hichrom RP18 (150 × 3.0 mm, 3 µm. UK) column interfaced with a LTQ Orbitrap mass spectrometer. The calibration range for omeprazole and omeprazole sulphone was 0.002–1 µg/mL, whereas, for 5-hydroxy omeprazole was 0.005–1 µg/mL. The extracted ion ranges ([M + H]+) were; m/z 346.12–346.13 for omeprazole, 362.11–362.12 for 5-hydroxy-omeprazole, and omeprazole-sulphone and 384.07–384.09 for pantoprazole. The regression equation for omeprazole was 0.071x + 0.445, for 5-hydroxy omeprazole was y = 0.08x + 0.017 and for omeprazole sulphone y = 0.007x + 0.05. This method was successfully applied for the determination of pharmacokinetic parameters of omeprazole and its metabolites in human vol...

Omeprazole (OMP) is effective in the treatment of gastric hyperacidity and is metabolized by CYP2C19 and CYP3A4. These enzymes are modulated by estrogen and progesterone which regulate the menstrual cycle. The variations in the pharmacokinetics (PK) of many drugs like amphetamine, benzodiazepines and caffeine have been reported during menstrual cycle. In present study, the PK of the omeprazole and its metabolites was investigated during various phases of the menstrual cycle. A single oral dose, open-label, non-controlled, pharmacokinetic study of omeprazole was conducted in healthy young/premenopausal females (n = 16). The PK of omeprazole, 5-hydroxy-omeprazole and omeprazole sulphone was evaluated in three phases of menstrual cycle. The blood samples were analyzed using reversed-phase HPLC coupled with UV detector and the PK data were evaluated. The activities of CYP2C19 and CYP3A4 were determined as AUC(OH-OMP)/AUC(OMP) and AUC(OMP-SUL)/AUC(OMP), respectively. Omeprazole showed significantly (p < 0.05) higher [Formula: see text] and CL/F in follicular and menstrual phases, respectively. The [Formula: see text] of 5-hydroxy omeprazole was also significantly (p < 0.05) higher in follicular phase. The metabolic ratios (MR) of 5-hydroxy omeprazole and omeprazole sulphone were lower in follicular phase compared with the luteal phase. The present study suggests that high estrogen levels of follicular phase may result in increased absorption of omeprazole. The lower MR for 5-hydroxy omeprazole and omeprazole sulphone in follicular phase as compared to luteal phase suggests that metabolism of omeprazole is low in follicular phase as compared to luteal phase, which is progesterone-dominant phase. However, the clinical significance for these findings needs to be determined.

The pharmacodynamics of absorption of local anaesthetics used during surgical procedures into tissues is governed by the amount of free drug in plasma. Toxicity may occur during continuous infusions if the levels of free drug become too high which may occur if the binding capacity of the α-1- acid glycoprotein present in plasma is exceeded. In order to monitor this a method was developed for the determination of the amount of free and bound ropivacaine in human plasma during knee and hip surgery. Rapid equilibrium dialysis units were used to separate free and bound drug then protein and buffer salts were removed by solvent precipitation. Analysis was carried out using a ZICHILIC HPLC column interfaced with an LTQ Orbitrap mass spectrometer. The following extracted ion ranges ([M+H] + ) were monitored: m/z 275.21-275.22 for ropivacaine and m/z 235.175-235.185 for lidocaine. The method was calibrated by spiking ropivacaine, and a fixed amount of lidocaine as internal standard, into plasma over the range 0.01–1.5 µg/ml. The equation of the line was y =0.886 x ±4.2% ( n =2), forcing the curve through zero since blank plasma was free of the analyte. The values obtained for the accuracy and precision of the analysis of plasma spiked at 0.03 µg/ml and 1.5 µg/ml were 93.2%±2.8% and 95.4%±1.5% respectively ( n =5). Repeat analysis of a patient sample for free and bound drug gave the following values for levels of ropivacaine: bound 1.63 µg/ml±1.48%, unbound 0.0671 µg/ml±1.68% ( n =5).

The kidneys are important organs which have many functions in the body, including the production of hormones, absorbtion of minerals and the filtration of blood, producing urine. Their failure can be fatal, therefore, to focus the study of such herbs which may be useful in treating renal disease is the need of hour. In Pakistan, Cucumis melo and Berberis vulgaris has been commonly used for renal problems. In both of these plants were found flavonoids, alkaloids and terpenes, which may stand for their renal protective properties. Their reported vitamin E contents and antioxidant potentials also provide a base for their defensive mechanism, may be due to their free radical scavenging properties. Further, their diuretic and urinary tract anti-ulcer properties also support their traditional use in renal diseases. Their anti-histaminic and anti-cholinergic properties also provide symptomatic treatment by decreasing prostaglandin level and due to antispasmodic properties. Concluding, both of these plants can be used for renal problems, especially Cucumis melo, which have both the nutritive and medicinal properties. Therefore, the renal disease patients are advised to take much of this particular fruit, especially their seeds to make their kidneys healthy.

A simple, rapid, and sensitive high performance liquid chromatographic method with UV detection has been developed for the quantification of clopidogrel in human plasma and pharmaceutical dosage form using diclofenac sodium as an internal standard and validated according to standard guidelines. The separation of clopidogrel and diclofenac sodium was achieved using Hypersil BDS RP18 (250 × 4.6 mm, 5 µm) at a column oven temperature of 35°C. The methanol and phosphoric acid 25 mM (80:20, v/v) (pH 3.0), used as a mobile phase in the isocratic mode was pumped at a flow rate of 1.2 mL min−1 and eluents were monitored at a wavelength of 220 nm. The retention times for diclofenac sodium and clopidogrel were 4.15 and 4.62 min, respectively. Extraction of drug from plasma was carried out with diethyl ether. The limit of detection (LOD) was 2.0 ng mL−1, while limit of quantification (LOQ) was 5.0 ng mL−1. The calibration curves were linear (r2 = 0.999) over the concentration range of 0.005 to 5.0 µg mL−1 for both s...

A novel isocratic reversed-phase high performance liquid-chromatography/ultraviolet detection method for simultaneous determination of cefdinir and cefixime in human plasma was developed and validated after optimization of various chromatographic conditions and other experimental parameters. Sample preparation based on a simple extraction procedure consisting of deproteination and extraction with 3 parts of 6% trichloroacetic acid aqueous solution followed by volume make up with the aqueous component of the mobile phase obtained best recoveries of the two analytes. Samples were separated on a Supelco Discovery HS C(18) (150 mm × 4.6 mm, 5 μm) analytical column protected by a Perkin Elmer C(18) (30 mm × 4.6 mm, 10 μm) guard cartridge. The mobile phase, methanol/acetonitrile (50/50, v/v):0.05% trifluoroacetic acid (19:81, v/v), operated at 50°C column oven temperature was pumped at a flow rate of 2.0 mL min(-1) and the column eluents were monitored at a wavelength of 285 nm. When Sample was injected into the Perkin Elmer high performance liquid-chromatography system through Rheodyne manual (or auto-sampler) injector equipped with 20 μL loop, separation was achieved within 4 min. The present method demonstrated acceptable values for selectivity, linearity within the expected concentration range (0.004-5.0 μg mL(-1); r(2)>0.999 for both analytes), recovery (>95% for cefdinir and >96% for cefixime), precision (%RSD

A highly sensitive, precise, and accurate reversed-phase high-performance liquid-chromatography/electrochemical detection method for simultaneous determination of the endogenous free α-lipoic acid and dihydrolipoic acid in biological matrices was developed and validated. The two analytes were extracted from the samples with acetonitrile/10% metaphosphoric acid solution(aqueous) (50/50 v/v). To determine the total lipoic acid, samples were treated with tris(2-carboxyethyl)phosphine solution in phosphate buffer, pH 2.5 with 85% orthophosphoric acid prior to deproteination. The two analytes were separated on a C18 (150 × 4.6 mm, 5 μm) analytical column using acetonitrile-50 mM phosphate buffer, pH 2.5 with 85% orthophosphoric acid (35/65 v/v) as the isocratic mobile phase pumped at a flow rate of 2.0 mL min−1 at the column oven temperature of 35 °C. The column eluents were monitored at a potential of 0.9 V. These analytes were efficiently resolved in 97%), precision (RSD%

A novel, precise, accurate and rapid isocratic reversed-phase high performance liquid chromatographic/ultraviolet (RP-HPLC/UV) method was developed, optimized and validated for simultaneous determination of rosuvastatin and atorvastatin in human serum using naproxen sodium as an internal standard. Effect of different experimental parameters and various particulate columns on the analysis of these analytes was evaluated. The method showed adequate separation for rosuvastatin and atorvastatin and best resolution was achieved with Brownlee analytical C18 column (150×4.6 mm, 5 μm) using methanol-water (68:32, v/v; pH adjusted to 3.0 with trifluoroacetic acid) as a mobile phase at a flow rate of 1.5 ml/min and wavelength of 241 nm. The calibration curves were linear over the concentration ranges of 2.0-256 ng/ml for rosuvastatin and 3.0-384 ng/ml for atorvastatin. The lower limit of detection (LLOD) and lower limit of quantification (LLOQ) for rosuvastatin were 0.6 and 2.0 ng/ml while for atorvastatin were 1.0 and 3.0ng/ml, respectively. All the analytes were separated in less than 7.0 min. The proposed method could be applied for routine laboratory analysis of rosuvastatin and atorvastatin in human serum samples, pharmaceutical formulations, drug-drug interaction studies and pharmacokinetics studies.

A rapid, inexpensive, sensitive and specific HPLC-ECD method for the determination of lipoic acid in human plasma was developed and validated over the linearity range of 0.001–10 μg/ml using naproxen sodium as an internal standard (IS). Extraction of lipoic acid and IS from plasma (250 μl) was carried out with a simple one step liquid–liquid extraction using dichloromethane. Similarly solid-phase extraction was carried out using dichloromethane as extraction solvent. The separated organic layer was dried under the stream of nitrogen at 40 °C and the residue was reconstituted with the mobile phase. Complete separation of both lipoic acid and IS at 30 °C on Discovery HS C18 RP column (250 mm × 4.6 mm, 5 μm) was achieved in 6 min using 0.05 M phosphate buffer (pH 2.5 adjusted with phosphoric acid):acetonitrile (50:50, v/v) as a mobile phase pumped at the rate of 1.5 ml/min using electrochemical detector in DC mode at the detector potential of 1.0 V. The limit of detection and limit of quantification of lipoic acid were 200 pg/ml and 1 ng/ml, respectively. While on column limit of detection and limit of quantification of lipoic acid were 10 and 50 pg/ml, respectively. The absolute recoveries of lipoic acid with liquid–liquid and solid-phase extraction were 98.43, 95.65, 101.45, and 97.36, 102.73, 100.17% at 0.5, 1 and 5 μg/ml levels, respectively. Coefficient of variations for both intra-day and inter-day were between 0.28 and 4.97%. The method is validated and will be quite suitable for the analysis of lipoic acid in the plasma of human volunteers as well as patients with diabetes and cardiovascular diseases.

A novel, simple and fast reversed-phase HPLC/UV method was developed, optimized for various chromatographic conditions, and validated according to international guidelines for simultaneous determination of all-trans-retinol and alpha-tocopherol in human serum using retinyl acetate as internal standard in the concentration of 0.5 microg/ml. A liquid-phase extraction was applied to the 250 microl of serum with n-hexane-dichloromethane mixture (70:30, v/v), in two steps, using ethanol-methanol mixture (95:5, v/v) for protein precipitation and BHT (butylated hydroxy toluene) as stabilizer for sample preparation. Both analytes were analyzed on Kromasil 100 C(18) column (150 mm x 4.6 mm, 5 microm), Brownlee analytical (Perkin Elmer) C(18) column (150 mm x 4.6 mm, 5 microm), and Supelco (Supelcosil) LC-18 column (150 mm x 3 mm, 3 microm), protected by a Perkin Elmer C(18) (30 mm x 4.6 mm, 10 microm; Norwalk, USA) pre-column guard cartridge, at 292 nm wavelength, using methanol-water (99:1, v/v), in isocratic mode as mobile phase applied at flow rate of 1.5 ml/min and 1 ml/min for both 5 microm and 3 microm columns, respectively. Complete separation of all the analytes was achieved in 3 and 6 min on 3 microm and 5 microm columns, respectively by injecting 20 microl of sample into the HPLC system by autosampler, keeping column oven temperature at 25 degrees C. Different particulate reversed-phase chromatographic columns were evaluated in order to select the best column in terms of sensitivity, selectivity, resolution and short run time of both the analytes and it was concluded that 3 microm columns are better to be used in clinical set up as well as in laboratories for the separation of these analytes in a shorter time as compared with 5 microm columns. The method was validated and applied for the analysis of all-trans-retinol and alpha-tocopherol in the serum of human volunteers.

A versatile isocratic reversed-phase liquid chromatographic/ultraviolet–visible detection method for simultaneous determination of all-trans-retinol and α-tocopherol in human serum was developed and validated after optimization of various chromatographic conditions and other experimental parameters. Analytes were separated on a Kromasil 100 RP18 (150 × 4.6 mm, 5 μm) analytical column protected by a Perkin Elmer RP18 (30 × 4.6 mm, 10 μm) guard cartridge. The mobile phase, methanol–water (96:04 v/v) was pumped at a flow rate of 2.2 mL min−1 and the column eluents were monitored at the wavelength of 292 nm using retinyl acetate (1.0 μg mL−1) as the internal standard for both analytes. Sample preparation was based on protein precipitation and stabilization with 2,6-bis(1,1-dimethylethyl)-4-methylphenol/ethanol and a two step extraction process using n-hexane followed by dichloromethane as extraction solvents. Sample size was kept 20 μL and separation of analytes was achieved in less than 7 min. The present method demonstrated acceptable values for specificity/selectivity, linearity within the expected concentration range, recovery, precision, sensitivity, stability of solutions, robustness, and system suitability specifications and tests. The method was used for monitoring all-trans-retinol and α-tocopherol concentrations in human serum samples and could also be applied to other sample matrices such as brain slices and cosmetic products if attention is paid to the extraction procedure.

Alcoholic extract and various fractions of Achyranthes aspera leaves, traditionally used in Pakistan for treatment of infectious diseases was screened for in vitro antibacterial and antifungal activity. The chloroform and butanol fractions were found to be the most active among the fractions, showing considerable antibacterial activity against Shigella flexneri and Escherichia coli. The highest activity was found in the ethylacetate fraction (17 mm zone of inhibition) against gram-negative (Salmonella typhi) bacteria, with MIC value as 0.29 mg/mL. In antifungal screening, moderate activity was shown by the chloroform fraction (50 % inhibition) against Microsporum canis, with MIC value as 0.25mg/mL. Considerable level of antifungal activity was depicted by crude extract, hexane and butanol fractions against Aspergillus flavus and Microsporum canis. The ability of various extracts of Achyranthes aspera to inhibit different strains of fungi and bacteria indicates its potential use for the treatment of microbial infections.

In present study four medicinal plants namely Valeriana wallichii, Xanthium strumarium, Achyranthes aspera and Duchesnea indica belonging to different families were collected in Khyber Pakhtunkhwa province and crude extract and subsequent fractions were analyzed for their inhibitory potential against acetylcholinesterase, butyrylcholinesterase and α-glucosidase enzymes. Valeriana wallichii, Xanthium strumarium and Achyranthes aspera were significantly active against cholinesterases. Chloroform and ethylacetate fractions of Valeriana wallichii exhibited significant activity against acetylcholinesterase (IC50: 61μg/ml) and butyrylcholinesterase enzymes (IC50: 58μg/ml), respectively. Similarly ethylacetate fraction of Achyranthes aspera showed significant activity against acetylcholinesterase (IC50: 61 μg/ml) and butyrylcholinesterase enzymes (IC50: 61 μg/ml), respectively. In case of α-glucosidase enzyme, the chloroform fraction of Xanthium strumarium exhibited significant inhibitory activity (IC50: 72 μg/ml) as compared to the standard compound acarbose (IC50: 483 μg/ml). Duchesnea indica showed no such activities.

In present study, the anti-inflammatory potential of three medicinal plants, Xanthium strumarium, Achyranthes aspera and Duchesnea indica were evaluated, using both in vitro and in vivo assays. Carrageenan induced hind paw edema model was used to carry out the in vivo anti-inflammatory activity, while for in vitro screening lipoxygenase inhibition assay was used. Crude extract of all the selected plants depicted significant (plt;0.001) anti-inflammatory activity, at late phase of inflammation. Achyranthes aspera also showed considerable anti-inflammatory activity (47%) at relatively lower concentration (200 mg/ml), at the initial phase of inflammation. Similarly the ethyl acetate fraction of all the selected plants showed significant lipoxygenase inhibition activity when compared with the standard drug (Baicalein). The results obtained from both in vitro and in vivo anti-inflammatory activity suggest that the ethyl acetate fraction of the crude extract of all the selected plants can be used for the isolation of new lead compounds with better anti-inflammatory activity.

Rosuvastatin is used to treat dyslipidemia and is metabolized by CYP2C9 that shows variable metabolic activity in males and females. Pharmacokinetics (PK) of drugs varies in males and females that may result in altered drug response and therapeutic efficacy. In current study, PK of rosuvastatin has been evaluated in males and females. A single oral dose (40 mg rosuvastatin), open-label and non-controlled PK study was arranged. A reversed phase HPLC method was applied for quantification of rosuvastatin in serum samples. PK parameters of rosuvastatin were compared in males and females by applying student t test at 95 % confidence interval. The C max, $$[{\text{AUC}} ]_{0}^{8}$$ and $$[{\text{AUC}} ]_{0}^{\infty }$$ of rosuvastatin was significantly higher (p 0.05) in males compared with females while CL/F was significantly (p

The objective of the current work was to develop and evaluate thermoreversible subcutaneous drug delivery system for Insulin. Thermoreversible in-situ gel system was developed and evaluated both in-vitro and in-vivo comprising of pluronic F-127 alone or in combination with methylcellulose in different ratios. The drug release kinetics and mechanism was predicted by applying various mathematical models to the in-vitro dissolution data. Rabbits were used as animal model following subcutaneous injection to predict various pharmacokinetic parameters by applying Pk-Summit® software. The in-vitro and in-vivo data revealed that the formulation IPM 15/3 consisting of the pluronic F-127 (15% w/v) and methylcellulose (3% w/v) was the most robust and capable formulation for extending the drug release and maintaining basal plasma insulin level between 10 and 40 µU/ml for 240 h (10 d).

A simple, specific, precise and rapid RP-HPLC-UV method was developed for simultaneous determination of lumefantrine and its metabolite desbutyl lumefantrine in human plasma. Experimental parameters were optimized and the method was validated according to standard guidelines. The method showed adequate separation for lumefantrine and desbutyl lumefantrine and best resolution was achieved with Supelco Discovery HS C18 RP (150mm×4.6mm, 5μm) column using acetonitrile and 0.05% trifluroacetic acid (70:30, v/v) as a mobile phase pumped at a flow rate of 1.0ml/min and wavelength of 335nm. The method was linear over the concentration range of 10-12,000ng/ml. The lower limit of detection (LLOD) and lower limit of quantification (LLOQ) for lumefantrine were 10.0 and 18.0ng/ml, while for desbutyl lumefantrine were 7.5 and 15.0ng/ml, respectively. The proposed method was efficiently applied for determination of lumefantrine and desbutyl lumefantrine concentrations in plasma samples for pharmacokinetic studies.

In vivo and in vitro screening of anti inflammatory activity of Valeriana wallichii and Achyranthes aspera leaves crude extract was performed, using standardized procedures. Methanolic crude extract topical formulation (cream) of Valeriana wallichii and Achyranthes aspera leaves (Family Valerianaceae and Amaranthaceae respectively), were screened for their anti-inflammatory activity, through "Carrageenan induced hind paw edema" test, for their effect on the acute and chronic phase inflammation models in male Wistar rats. Methanolic extract and its fractions were also evaluated for their in vitro anti-inflammatory activity using lipoxygenase inhibition assay. Leaves of Valeriana wallichii showed significant (P0.001), dose dependant anti inflammatory activity, comparable with that of the standard, in animal model. The ethyl acetate fraction of Valeriana wallichii also showed considerable (IC 50=73 ± 0.36) in vitro anti-inflammatory activity as compared to standard (6.11 ± 0.02). Similarly Achyranthes aspera leaves showed relatively weak (p0.05) in vivo anti-inflammatory activity. However, its activity was comparable with that of standard at 10% concentration after 5 hrs of carrageenan injection. This activity was present in ethyl acetate fraction during in vitro screening (IC 50=76 ± 0.14) as compared to that of standard (IC 50=6.11 ± 0.02). The combined in vitro and in vivo Anti-inflammatory screening shows that the ethyl acetate fraction of the crude extract of Valeriana wallichii and Achyranthes aspera can be used for the isolation of new Anti-inflammatory lead compounds.

A highly sensitive and rapid liquid chromatography–tandem mass spectrometry method was developed and validated for the determination of artemether and its metabolite dihydroartemisinin in human plasma using artemisinin as an internal standard. Chromatographic separation was achieved on a Supelco Discovery HS C18 RP column (150 mm × 4.6 mm, 5 µm; Bellefonte, USA) using acetonitrile and water with 0.1 % formic acid (80:20, v/v) as a mobile phase in isocratic mode. A high-resolution Thermo Electron Corporation LTQ-Orbitrap mass spectrometer (San Jose, USA) was used in single ion monitoring (SIM) mode using atmospheric pressure chemical ionization (APCI) as an interface. The following extracted ion ranges ([M + H]+) were monitored: m/z 267.14–267.16 for artemether, m/z 221.16–221.18 for dihydroartemisinin and m/z 283.14–283.16 for internal standard. The limit of detection (LOD) and limit of quantification (LOQ) for artemether were 0.3 and 0.8 ng mL−1, while for dihydroartemisinin were 0.2 and 0.6 ng mL−1, respectively. The validated method was successfully applied to the quantification of artemether and dihydroartemisinin in plasma samples of healthy volunteers participating in pharmacokinetic drug–food interaction studies.

A new, simple, economical and validated high-performance liquid chromatography linked with electrochemical detector (HPLC-ECD) method has been developed and optimized for different experimental parameters to analyze the most common monothiols and disulfide (cystine, cysteine, homocysteine, methionine, reduced (GSH) and oxidized glutathione (GSSG)) and ascorbic acid present in human plasma and erythrocytes using dopamine as internal standard (IS). Complete separation of all the targets analytes and IS at 35°C on Discovery HS C18 RP column (250 mm × 4.6mm, 5 μm) was achieved using 0.05% TFA:methanol (97:3, v/v) as a mobile phase pumped at the rate of 0.6 ml min(-1) using electrochemical detector in DC mode at the detector potential of 900 mV. The limits of detection (3 S/N) and limits of quantification (10 S/N) of the studied compounds were evaluated using dilution method. The proposed method was validated according to standard guidelines and optimization of various experimental parameters and chromatographic conditions was carried out. The optimized and validated HPLC-ECD method was successfully applied for the determination of the abovementioned compounds in human plasma and erythrocytes. The method will be quite suitable for the determination of plasma and erythrocyte profile of ascorbic acid and aminothiols in oxidative stress and other basic research studies.

BackgroundApproximately 68 brands of azithromycin capsule formulations are available in Pakistan; however, published data on their bioequivalence in the Pakistani population are not available.ObjectiveUpon instructions from and approval of the Ministry of Health, Pakistan, this study was designed to evaluate the bioequivalence of a locally manufactured azithromycin capsule formulation with a reference formulation from a multinational manufacturer. This study compared dissolution profiles, relative bioavailability, and other pharmacokinetic parameters of the 2 formulations.MethodsA single oral 500-mg dose of the 2 formulations was administered to 12 healthy adult Pakistani male volunteers under fasting conditions in a randomized, open-label, 2-period crossover study. The trial included collection of blood samples over 48 hours and a 2-week washout period. Azithromycin serum concentrations were quantified using a validated RP-HPLC/ultraviolet (UV) detection method. These results were used to determine the intended pharmacokinetic parameters. As mandated by the US Food and Drug Administration and the European Medicine Agency, the test and reference formulations were considered bioequivalent if the 90% CIs of the geometric mean ratios for the log-transformed values of their pharmacokinetic parameters were within the predetermined range of 0.8 to 1.25.ResultsWhen subjected to a simple model independent approach of dissolution profile comparison, f1 (difference) and f2 (similarity factor) were found to be 5.47 and 70.04, respectively. Similarly, the 2 azithromycin capsule formulations were well tolerated by all volunteers. Low %CV of the pharmacokinetic parameters at a sample size of 12 and significance level of 0.05 contributed to acceptable (>0.8) power of the test. The 90% CIs for the ratios of Cmax, AUC0–48, Tmax, t1/2, and mean residence time, respectively, were 0.83–0.93, 0.85–1.10, 0.86–1.08, 0.92–1.17, and 0.92–1.16.ConclusionThis single-dose study found that test and reference formulations met the regulatory criteria for bioequivalence in these fasted, healthy male Pakistani volunteers.