Effect of chloroquine pre-treatment on the metoclopramide's pharmacokinetics after their co-administration.

BACKGROUND: This study evaluated the pharmacokinetic interactions of orally administered chloroquine and metoclopramide. METHODS: The study employed a randomized and two-phase cross-over design with 4-week washout plan. Twelve healthy male volunteers were shortlisted according to the set criteria and were administered with metoclopramide 10 mg PO and chloroquine (a total of 1500 mg) at different intervals which were (500 mg at 0, 6, and 24 h). The concentration of chloroquine and metoclopramide in the blood samples was estimated using a validated HPLC-UV technique to affirm the maximum concentration (Cmax), time to reach Cmax (Tmax), and area under the curve (AUC). RESULTS: Cmax, T1/2, and AUC of metoclopramide were increased up to 20, 10, and 47.8%, respectively, by the concomitantly administering Chloroquine. Chloroquine-treated phase showed increased values of Cmax (ng/ml), AUC (ng.h/ml), and T½ (h), i.e. 41.35 ± 1.61, 504.12 ± 66.25, and 5.72 ± 2.63, as compared to that reference phase i.e. 34.52 ± 4.92, 341.14 ± 112.8, and 5.19 ± 1.14, respectively. CONCLUSIONS: Chloroquine was found to attenuate CYP2D6 activity in healthy Pakistani male volunteers. Hence, patients that are prescribed with metoclopramide or other CYP2D6-substrate drugs require a dose adjustment when administered with chloroquine.

SPE-UHPLC-ESI-MS/MS Analysis of Cocaine and Its Metabolites in Conventional and Alternative Biological Specimens: Application to Real Samples.

An increase in cocaine abuse has been observed globally since the past decade. Cocaine is among the commonly abused stimulants used for recreational purposes. In this study, the SPE-UHPLC-MS/MS method was developed and validated to be applied on real specimens of 20 chronic cocaine abusers to quantify cocaine/metabolites in conventional as well as alternative biological matrices. Cocaine was extracted from biological specimens using solid-phase extraction followed by liquid chromatography tandem mass spectrometry analysis. Chromatographic separation was achieved on a Poroshell120EC-18 column (2.1 mm × 50 mm, 2.7 µm particle size) using water-acetonitrile in 0.1% formic acid as a mobile phase in gradient elution mode. The flow rate of the mobile phase was 0.5 mL/min with a gradient varying the percentage of acetonitrile linearity ranging 15-95% in 6.0 min acquisition time, and the injection volume was set at 5 µL. Positive electrospray ionization with multireaction ion monitoring mode using two ion transitions for cocaine/metabolites and one for cocaine-d3 was employed. The quantification method demonstrated good linear ranges of 0.025-250 ng/mL in blood, urine, and oral fluid (ng/mg for hair and nail) with a ≥0.991% determination coefficient. The detection limit and lower quantification limit were 0.005 and 0.025 ng/mL in all matrices, respectively. The mean extraction recovery and ionization suppression ranged from 89.3 to 99.8% and -4.6 to -14.4% in the studied matrices. Within-run and between-days precisions were 1.8-7.2% and 1.9-6.1%, respectively. This study will not only help in quantifying cocaine/metabolites in alternative specimens (hair, nail, and oral fluid) but also guide clinical and forensic toxicologists in interpretation of exhumation cases. Furthermore, multiple specimens' analyses can be of significance in estimating the time/manner of drug exposure, in confirming the results of laboratories in cases of doubtful clinical histories, or in aiding medico-legal investigations.

Spilanthes acmella Extract-Based Natural Oils Loaded Emulgel for Anti-Microbial Action against Dermatitis.

BACKGROUND: Dermatitis is skin disorder that is complicated by recurrent infections of skin by bacteria, viruses, and fungi. Spilanthol is an active constituent of Spilanthes acmella, which possess strong anti-bacterial properties. The purpose of this study was to develop a herbal emulgel for the treatment of dermal bacterial infections, as microscopic organisms have created solid resistance against anti-microbials. METHODS: Emulgels were prepared and characterized for parameters such as physical examination, rheological studies, spreading coefficient, bio-adhesive strength measurement, extrudability study, antibacterial activity, FTIR analysis, in vitro drug dissolution, and ex vivo permeation studies. RESULT: With a statistically significant p-value = 0.024, 100% antibacterial activity was observed by F4 against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli (mean ± S.D) (25.33 ± 0.28, 27.33 ± 0.5, and 27 ± 0.5). However, maximum antibacterial effect 100% formulations produced zones of inhibitions against E. colip-value = 0.001. The mean zone of inhibition produced by F4 was greatest among all at 26.44 ± 0.37 mm (mean ± S.D). The F4 formulation produced a maximum percentage dissolution, permeation, and flux of 86.35 ± 0.576, 55.29 ± 0.127%, and 0.5532 ug/cm2/min, respectively. CONCLUSIONS: The present study therefore, suggests the use of S. acmella extract and olive oil containing emulgel for treating bacterial skin infections.

A Hematological and Histopathological Study on Diphenhydramine Nasal Nano-gel and Nano-emulgel for the Management of Allergic Rhinitis in Animal Model.

The study aims to determine histamine efficacy on hematologic values in experimental animal model, under physiological and pathological conditions after inducing diphenhydramine-formulated nasal nano-gel/nano-emulgel in comparison with conventional nasal spray regime. In this study, we conducted experiment on New Zealand white male rabbits to prove our hypothesis that nasal diphenhydramine nano-gel and nano-emulgel can penetrate the nasal mucosa faster to show drug response and subside histaminic symptoms than market nasal spray (as reference). Blood samples from 48 New Zealand white male rabbits, under both experimental conditions (physiological and pathological) divided into four groups for each (n = 6) were investigated after inducing each dosage form intranasally. Hematologic parameters (WBCs, RBCs, HGB, PLTs, lymphocytes, monocytes, eosinophils, granulocyte counts) were analyzed in whole blood samples, collected at different time intervals. ANOVA and completely randomized design (CRD) were applied for statistical analysis. Histopathologically, nasal tissues of all groups were analyzed to see intramucosal surface changes. Data of descriptive statistics of hematological parameters analyzed at confidence level 95% showed that under physiological condition, hematological parameters of all groups were lying in normal range, whereas under pathological condition, low values of all hematological parameters were observed in all groups due to allergenic condition. The groups B (allergenic rabbits treated with formulated diphenhydramine nasal nano-gel) and C (allergenic rabbits treated with formulated diphenhydramine nasal nano-emulgel) have shown good changes in the treatment of allergenic rabbits as compared to group D (allergenic rabbits treated with formulated diphenhydramine nasal spray). The completely randomized ANOVA and Tukey HSD all-pairwise comparison tests of hematological parameters were applied that showed all groups in both studies were significantly different from each other. It was observed after histopathological study of nasal membrane tissues that change in mucosa has occurred due to the passage of drug. In summary, hematological profile and histopathological study have demonstrated the comparable results with conventional diphenhydramine nasal spray and formulated diphenhydramine nasal nano-gel/nano-emulgel which can exhibit considerable drug delivery dosage forms in the management of allergic rhinitis in animal model.

Assessment of formulation variables of poor water soluble diacerein for its improved loading and anti-inflammatory activity.

Dissolving microneedles have become a popular method for percutaneous administrationof drugs. However, loading poorly soluble drugs into water-based dissolving microneedles remains a challenge. In view of this, we aimed to improve Diacerein (DCN) solubility formulating dissolving microneedles. DCN microsuspension was created by high-speed homogenization with organic solvents or wet milling with Tween 80 as a stabilizer (LD1). They were analyzed for particle size and saturation solubility. Subsequently, the organic solvent-based microneedles were prepared under vacuum, whereas LD1 was mixed with HPMC (8% w/w) and PVP (30% w/w) matrix to concentrate the drug in acral fraction through centrifugation. DCN microsuspension in DMSO had the highest drug solubility with an average particle size of 6 µm, whereas LD1 had a particle size of 3.28 µm showing improved solubility. TD-3 had the highest drug loading and the least amount of drug migration into the blank baseplate. Within 5 min, these microneedles dissolved completely in an agarose-gel block. LD1 was likewise put in the baseplate to generate TD3-B. Within 24 h, 74.39% of the medication was released from TD3-B, with only a small amount remaining in the baseplate. TLC examination indicated the conversion of DCN to Rhein in the skin, whereas DSC and TGA studies revealed amorphous features. DCN microneedles showed no sign of skin irritancy but showed anti-inflammatory response on carrageenan-induced paw edema model. Microneedles remained stable during accelerated stability testing. Wet milling in the presence of a stabilizer can be an effective approach for enhancing DCN solubility for improved drug loading in dissolving microneedles. Improvement in solubility of Diacerein for subsequent loading in Dissolving Microneedle for percutaneous delivery.

Amidated Pluronic Decorated Muco-Penetrating Self-Nano Emulsifying Drug Delivery System (SNEDDS) for Improved Anti-Salmonella typhi Potential.

The enteric system residing notorious Salmonella typhimurium (S. typhi) is an intracellular, food-borne, and zoonotic pathogen causing typhoid fever. Typhoid fever is one of the leading causes of mortality and morbidity in developing and underdeveloped countries. It also increased the prevalence of multidrug resistance globally. Currently, available anti-bacterial modalities are unable to penetrate into the intracellular compartments effectively for eradicating S. typhi infection. Therefore, in this study, we developed nanostructured lipid-based carriers in the form of a self-nanoemulsifying drug delivery system (SNEDDS) for targeted delivery of ciprofloxacin (CIP) into the S. typhi intracellular reservoirs. Capryol 90, Tween 80, and Span 20 were finalized as suitable oil, surfactant, and co-surfactant, respectively, according to the pseudoternary phase diagram emulsifying region. Targeting capability and mucopenetration of the SNEDDS was attributed to the inclusion of amidated pluronic (NH2-F127). Developed NH2-F127 SNEDDS were characterized via physicochemical, in vitro, ex vivo, and in vivo evaluation parameters. The size of the SNEDDS was found to be 250 nm, having positively charged zeta potential. In vitro dissolution of SNEDDS showed 80% sustained release of CIP in 72 h with maximum entrapment efficiency up to 90% as well as good hemocompatibility by showing less than 0.2% hemolysis and 90% biocompatibility. The survival rate of S. typhi in macrophages (RAW 264.7) was minimal, i.e., only 2% in the case of NH2-F127 SNEDDS. Macrophage uptake assay via nanostructures confirmed the maximum cellular uptake as evidenced by the highest fluorescence. Biofilm dispersion assay showed rapid eradication of developed resistant biofilms on the gall bladder. In vivo pharmacokinetics showed improved bioavailability by showing an increased area under the curve (AUC) value. Taken together, NH2-F127-SNEDDS can be utilized as an alternative and efficient delivery system for the sustained release of therapeutic amounts of CIP for the treatment of S. typhi.

Formulation and optimization of dimenhydrinate emulgels for topical delivery using response surface methodology.

Development of dimenhydrinate (DMN) emulgel formulation has been described in this work with enhanced permeation for transdermal delivery of DMN for effective management of motion sickness. Various DMN emulgel formulations were prepared using central composite design in response surface methodology. Propylene glycol and olive oil were used in varying ratios as permeation enhancers along-with carbopol-934 as gelling agent. Prepared formulations were evaluated by physico-chemical properties, stability and Fourier transform infrared spectroscopy (FTIR) studies. In-vitro drug release was studied using cellophane membrane. Formulation F2 showed maximum drug permeation following diffusion-based release mechanism and was used in further studies. Rat skin was used in Franz cell for ex-vivo studies to determine various permeation kinetic parameters. FTIR studies provided no evidence of chemical interaction between DMN and polymers used, whereas molecular docking revealed formation of a stable complex in the presence of aqueous environment with stable intermolecular binding and the complex was well hydrated. No evidence of skin irritation was observed in human volunteers following application of the optimized formulation. Histopathology data of the rat skin showed a decreased proliferation of the lymphocytes whereas monocytes were induced. In conclusion, combination of propylene glycol and olive oil was successfully employed for delivery of DMN through transdermal route with good permeability and prolonged release time that can be highly beneficial in treating motion sickness in unusual circumstances.

Thiolated sodium alginate conjugates for mucoadhesive and controlled release behavior of metformin microspheres.

The absorption of BCS III drugs can be improved by inhibiting the P-glycoprotein (P-gp) efflux and by increasing the mucoadhesion of natural polymers. In the present study, an esterification of sodium alginate (SA) with thioglycolic acid (TGA) was applied for the preparation of thiolated sodium alginate (TSA). The Ellman's test was applied to quantify the thiol group and a di-sulphide bond test was performed to confirm any SS linkages. The FTIR, DSC, XRD, 1H NMR and charring point determinations were confirmed the thiol group of TSA. The gel like rheological properties with porcine mucous was confirmed by viscoelasticity properties and the mucoadhesion with the rabbit intestine was carried out after compression of 30 mg tablets of TSA. The content of thiol group was in the range of 320-730 µmoL/g of the polymer. The FTIR spectrum showed a characteristic peak of sulfhydryl group at 2557 cm-1 in TSA and the reduction of the charring point from 220 °C to 178 °C was confirmed the thiolation of TSA. A direct relationship of mucoadhesion and swelling was observed with the concentration of TGA and SA, respectively. The prepared microspheres were 2-7 µm in size, excellent rheological properties and non-fickian drug release behavior was observed.

Effect of clarithromycin pre-treatment on the pharmacokinetics of metoclopramide after their simultaneous oral intake.

OBJECTIVE: The objective of this study was to assess the influence of enzyme suppression on the values of various pharmacokinetic factors of orally administered metoclopramide. METHOD: This study was conducted in two phases and a 4-week duration was adopted for drug washout. This randomized study involved 12 healthy human volunteers who received a single oral dose of metoclopramide 20 mg. After the washout period, volunteers received clarithromycin 500 mg two times per day for consecutive 5 days. On test day (fifth day), a single oral dose of metoclopramide 20 mg was also given to the volunteers, and collection of blood samples was conducted at pre-decided time points. Various pharmacokinetic parameters such as Cmax, Tmax, and AUC0-∞ of metoclopramide were determined by analyzing the blood samples using a validated HPLC-UV method. RESULTS: Clarithromycin increased the mean values of Cmax, AUC0-∞, and T1/2 of metoclopramide by 46%, 78.6%, and 9.8%, respectively. CONCLUSION: Clarithromycin noticeably increased the concentration of plasma metoclopramide. This study's results provide in vivo confirmation of the CYP3A4 involvement in metoclopramide metabolism, in addition to CYP2D6. Therefore, metoclopramide pharmacokinetics may be clinically affected by clarithromycin and other potent enzyme inhibitors.

Influence of Rifampicin Pre-treatment on the In vivo Pharmacokinetics of Metoclopramide in Pakistani Healthy Volunteers Following Concurrent Oral Administration.

BACKGROUND: Metoclopramide is metabolized by various cytochrome P450 (CYP) enzymes such as CYP3A4, CYP1A2, CYP2D6, CYP2C9, and CYP2C19. Rifampicin is a non-selective inducer of P-glycoprotein (P-gp) and CYP enzymes such as CYP3A4 and others. OBJECTIVE: This study was aimed at the evaluation of rifampicin's enzyme induction effect on the pharmacokinetic parameters of orally administered metoclopramide. METHOD: This randomized, single-blind, two-phase cross-over pharmacokinetic study separated by a 4-week washout period was conducted at a single center in Pakistan. It involved twelve Pakistani healthy male volunteers (nonsmokers) divided into two groups. In the reference phase, each volunteer received a single oral dose of 20 mg metoclopramide (Maxolon 10 mg, GlaxoSmithKline, Pakistan), while in the rifampicin-treated phase, each volunteer received 600 mg rifampicin once daily for 6 days through oral route. On day 6, metoclopramide (20 mg) was administered 2 hours after the last pretreatment dose of rifampicin. The serial blood samples were collected on predetermined time points (0, 0.5, 1, 1.5, 2, 3, 4, 6, 8, 10, 12, 14, and 18 h) and analyzed using a validated HPLC method for the determination of pharmacokinetic parameters, i.e. Cmax, Tmax, and AUC0-∞ of metoclopramide. The whole study was monitored by an unblinded clinician for the purpose of volunteer's health safety. RESULTS: All the volunteers participated in the study until the end. Twelve healthy Pakistani males having mean age 26.0 (range 20.6-34.1) years and body mass index 25.1 (range 16.2-31.5) kg/m2 were included in this study after taking written informed consent. Rifampicin significantly (P<0.05) decreased the mean Cmax, AUC0-∞ and T1/2 of metoclopramide by 35%, 68%, and 44%, respectively. The laboratory tests did not reveal any significant change in the biochemical, physical, hematological, or urinalytical values before and after metoclopramide treatment. None of the volunteers complained of any discomfort during the study. CONCLUSION: Rifampicin noticeably decreased the concentration of plasma metoclopramide. These results give in vivo confirmation of the CYP3A4 involvement in the metoclopramide metabolism, in addition to CYP2D6. Therefore, metoclopramide pharmacokinetics may be clinically affected by rifampicin and other potent enzyme inducers.

Development and validation of RP-HPLC method for determination of Lornoxicam in rabbit's plasma.

A simple, rapid and accurate reverse phase high performance liquid chromatographic (RP- HPLC) method was developed for the quantification of lornoxicam in oral disintegrating tablets (ODTs) and in rabbit's plasma. C18 Hypersil™ column was used as stationary phase to separate the drug. Mobile phase methanol: acetonitrile: water (60:30:10) was run isocratically at flow rate of 1 mL/min at room temperature. Mean retention time was 4.23 minutes and minimum amount of lornoxicam that can be measured was 7 ng/mL in rabbit's plasma. Good linearity was observed in concentration range of 10-100 ng/mL with regression coefficient R2 value of 0.9989 and slope value 23773. As per ICH norms, developed method was validated in terms of interday, intraday precision, accuracy, specificity, limit of detection (LOD), limit of quantification (LOQ) and drug plasma stability studies. All the data obtained revealed that this method can be used for in-vitro and in-vivo determination of lornoxicam in various pharmaceutical preparations.

Hepatoprotective and hepatocurative effects of Spilanthes acmella Murr against paracetamol induced hepatotoxicity.

Hepatotoxicity is appreciably escalating health dilemma worldwide and the degree of the problem has encouraged importance in the exploration for hepatotherapeutic agents from plants. In the current research work, the hepatoprotective/hepatocurative activity of methanolic extract of Spilanthes acmella Murr aerial parts in paracetamol induced hepatotoxicity was investigated in rabbits by the analysis of different liver enzymes including ALT, AST, ALP along with histopathological investigations. In first phase of the study, paracetamol toxicated rabbits were treated with extract and standard drug jatepar TM. The hepatotoxicant (paracetamol) significantly increased the levels of aspartate transaminase, alanine transaminase, alkaline phosphatase compared to normal control. Spilanthes acmella Murr at (400 mg/kg) reversed the elevation in the level of ALP, AST and ALT caused by the hepatotoxicants and jeteparR TM (standard) also reversed the deleterious effects of the hepatotoxicants. In second phase of this study, extract of Spilanthes acmella Murr was given to rabbits for ten days then paracetamol was administered in one group and level of liver parameters was paralleled with regular control group and the group that was receiving the extract. It is concluded that methanolic extract of Spilanthes acmella Murr aerial parts possesses hepatocurative and hepatoprotective activity.

Synthesis and Characterization of pH-Sensitive Genipin Cross-Linked Chitosan/Eudragit® L100 Hydrogel for Metformin Release Study Using Response Surface Methodology.

BACKGROUND: In this study, central composite design was utilized for the optimization of genipin cross-linked chitosan/Eudragit®-L 100 interpenetrating hydrogel network films fabricated through solvent evaporation technique. METHODS: Hydrogel formulations were studied using response surface methodology; regression analysis and the surface plots were used to evaluate the effect of variables on T50% (the time for 50% of drug release) and dynamic swelling with optimum formulation selection. Initial burst release of drug was observed from the formulated hydrogels during the first 2 hours of dissolution at simulated gastric pH 1.2 and then slow release during the next 10 hours in the simulated intestinal fluid at pH 7.4. Different polymer ratios in formulation showed significant influence on T50% and dynamic swelling of hydrogel. The highest T50% was observed at 9.89 hour and dynamic swelling at 7.86 h. RESULT: It was observed that by changing the polymer ratio with cross-linker, release rate of metformin could be modified. Cross-linker also affects drug release rate, i.e. the release rate is decreased with the increase in its concentration. The physical state of hydrogel was investigated by scanning electron microscope. CONCLUSION: It indicated the uniform distribution of drug in hydrogel matrix system. Moreover, the presence of hydrogen and ionic bonds between polymers and crosslinking agent formed interpenetrating hydrogel network, likely responsible for increased value of T50%, as confirmed by FTIR. Acute oral toxicity study was performed to investigate the toxic effect of crosslinking agent and polymer used in formulations.

Formulation Development and Evaluation of Diphenhydramine Nasal Nano-Emulgel.

The aim of present study is to formulate diphenhydramine nasal nano-emulgels, having lipophilic nano-sized interior droplets, with better penetration for targeted controlled delivery to mucous membrane. Different diphenhydramine (DPH) nasal nano-emulgels were developed having propylene glycol and olive oil (as permeation enhancers) by using RSM for optimization and then evaluated for physico-chemical characteristics and thermal stability. In-vitro drug release through cellophane membrane was conducted and results were analyzed statistically. Further, gelation, mucoadhesive stress, and ex-vivo and histopathological studies were performed on optimized formulation by using goat nasal membrane. Among all formulations, E2 showed maximum DPH release at higher concentration olive oil (4%) and lower concentration propylene glycol (PG) (25%) within 4 h. All formulations have followed first-order kinetics and drug release mechanism was Fickian diffusion. Analysis of variance (ANOVA) and multiple linear regression analysis (MLRA) were used to compare results among formulations and 3D surface plots were constructed also. Optimized formulation showed immediate prolong gelation in artificial nasal mucosa and excellent mucoadhesive property (72.5 ± 1.5 dynes/cm2). Approximately 97.1% optimized formulation was permeated through membrane within 4 h, having a high flux rate (33.19 ± 0.897 µg/cm2/min) with diffusion coefficient (0.000786 ± 4.56 × 10-5 cm2/min) while drug contents remained on mucosal membrane for 24 h. Histopathologically, change on intra-mucosal surface of excised membrane was observed due to passage of drug through it. In summary, combination of PG and olive oil in nasal DPH nano-emulgel can be utilized successfully for targeted controlled delivery. The optimized formulation has excellent permeability and prolonged residence time on mucosal surface, which prove its good anti-histaminic activity in case of allergic rhinitis.

Formulation, Evaluation and release rate characteristics of medicated jelly of vitamin C.

Medicated jelly formulations are patient friendly dosage form for pediatric, geriatric and dysphagic patients. These formulations offer rapid dissolution and absorption of drugs through oral mucosa therefore show the early onset of action. The objective of the study was to develop and evaluate oral jelly formulations of vitamin C. Slurry method was adopted using glucose 103gm, sugar 67gm, gelatin 10gm and sorbitol 6.56gm. Preformulation studies were performed including the organoleptic profile, pH, and solubility of both drugs. The medicated jelly of Vitamin C was prepared and evaluated for physical characteristics, weight variation, syneresis, pH, taste and palatability, drug content, release rate characteristics and stability studies. All the jellies were found to have patient welcoming taste and were palatable. All formulations showed more than 50% drug release within 15 minutes, while 93% drug was released in 30 minutes. The results of release kinetics showed that the formulation followed the zero order release kinetics. Thus the drug was released at constant rate independent of the drug concentration involved in the process. All the medicated jellies were found to remain stable stored for 60 days at different temperatures. The present study revealed that medicated jellies of vitamin C could be employed orally in an effective form as an alternative solid oral dosage form for special population such as pediatrics, geriatrics and patients with dysphagia.

The influence of the acyl chain on the transdermal penetration-enhancing effect of synthetic phytoceramides.

BACKGROUND/AIMS: The skin has become very attractive as a route for drug administration. Optimization of topical drug formulations by the addition of penetration enhancers may facilitate the passage of drugs through the stratum corneum. METHODS: In this paper, the skin penetration effect of phytosphingosine and 9 derived phytoceramides (PCERs) on 3 transdermal model drugs (i.e. caffeine, testosterone, ibuprofen) was investigated via Franz diffusion cell experiments using split-thickness human skin. Azone was included as a positive control. RESULTS: The main finding in our study was that the PCERs exerted a compound-dependent penetration-enhancing effect. Some of the investigated PCERs exhibited a penetration-enhancing ratio of more than 2 (mean ± SE): for caffeine PCER1 (2.48 ± 0.44), PCER2 (2.75 ± 0.74), PCER3 (2.62 ± 0.93) and PCER6 (2.70 ± 0.45) and for testosterone PCER1 (2.08 ± 0.56), PCER2 (2.56 ± 0.13), PCER3 (3.48), PCER4 (2.53), PCER5 (2.04 ± 0.14), PCER6 (2.05 ± 0.48) and PCER10 (4.84 ± 0.79), but none of them had an influence on ibuprofen. CONCLUSION: The investigated PCERs exhibited a penetration-enhancing effect on caffeine and testosterone but not on ibuprofen.

Improved physicochemical characteristics of artemisinin using succinic acid.

Artemisinin (ARMN) is a potent antimalarial drug, which is effective against multidrug resistant strains of Plasmodium falciparum and produces rapid recovery even in patients with cerebral malaria. Being poorly soluble in water, artemisinin is incompletely absorbed after oral intake due to poor dissolution characteristics in the intestinal fluids. To enhance these properties, solid dispersions of artemisinin with succinic acid (SUC) were prepared using drug-carrier ratios 1 : 1, 1 : 4, 1 : 6, 1 : 8 and 1 : 10 by solvent evaporation and freeze drying methods. These solid dispersions were characterized by differential scanning calorimetery (DSC), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction patterns (XRD), phase solubility and dissolution kinetics evaluated by applying zero order, first order, Higuchi, and Korsmeyer-Peppas models. Physical mixtures produced significantly higher aqueous solubility and rate of dissolution as compared to artemisinin alone. The dissolution profiles of all formulations followed Higuchi model and exhibited diffusion-controlled release of drug. Solvent evaporation method (SLVPs) exhibited improved solubility and freeze dried solid dispersions (FDSDs) produced highest solubility but stability constant was opposite. ARMN and SUC both were found completely crystalline as shown by their XRD patterns. Physical mixtures (PMs) showed reduced intensity in their XRD patterns while solid dispersions by SLVPs exhibited twice reduced intensity and much displaced angles, whereas FDSDs showed synergistic effects in some of ARMN and SUC peaks. DSC thermograms of FDSDs at drug-carrier ratios 1 : 1-1 : 4 showed lower melting temperature and enthalpy change (deltaH) values than respective SLVPs, whereas at higher ratios, a reverse was true. SLVPs showed displaced methyl stretching bands at lower drug-carrier ratios and exhibited O-H stretching characteristic bands of SUC at higher drug-carrier ratios. In addition, carbonyl group and C-O stretching vibrations characteristic of SUC (1307 cm(-1)) appeared prominently compared to PMs, whereas C-O stretching characteristic bands of ARMN disappeared at higher ratios. FDSDs exhibited distinct nature of bonding compared to respective SLVPs and PMs.

Development of solid dispersions of artemisinin for transdermal delivery.

Solid dispersions of the poorly soluble drug artemisinin were developed using polymer blends of polyvinylpyrrolidone (PVP) and polyethylene glycol (PEG) with the aim of enhancing solubility and in vitro permeation of artemisinin through skin. Formulations were characterised using a combination of molecular dynamics (MD) simulations, differential scanning calorimetry (DSC), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Solubility of artemisinin was determined in two solvents: de-ionised water and phosphate buffered saline (PBS; pH 7.4), while in vitro drug permeation studies were carried out using rabbit skin as a model membrane. MD simulations revealed miscibility between the drug and polymers. DSC confirmed the molecular dispersion of the drug in the polymer blend. Decrease in crystallinity of artemisinin with respect to polymer content and the absence of specific drug-polymer interactions were confirmed using XRD and FT-IR, respectively. The solubility of artemisinin was dramatically enhanced for the solid dispersions, as was the permeation of artemisinin from saturated solid-dispersion vehicles relative to that from saturated solutions of the pure drug. The study suggests that high energy solid forms of artemisinin could possibly enable transdermal delivery of artemisinin.

Albumin as a drug delivery and diagnostic tool and its market approved products.

Albumin is one of the most extensively studied endogenous proteins which are used in the fabrication of drug delivery and diagnostic technologies during last 10 years. This review provides a summary of products involving the use of albumin as a drug delivery tool for getting better the pharmacokinetics of a drug by developing the targetted drug delivery systems and diagnosing the pathologies. Using albumin, following market approved products have been developed: Levemir and Victoza (antidiabetic product), Abraxane (antimetastatic breast cancer product), and Nanocoll and Albures (for lymphoscintigraphy and diagnosis of cancer and rheumatoid arthritis).

Influence of cellulose derivative and ethylene glycol on optimization of lornoxicam transdermal formulation.

Lornoxicam containing topically applied lotions were formulated and optimized with the aim to deliver it transdermally. The formulated lotions were evaluated for pH, viscosity and in vitro permeation studies through silicone membrane using Franz diffusion cells. Data were fitted to linear, quadratic and cubic models and best fit model was selected to investigate the influence of variables, namely hydroxypropyl methylcellulose (HPMC) and ethylene glycol (EG) on permeation of lornoxicam from topically applied lotion formulations. The best fit quadratic model revealed that low level of HPMC and intermediate level of EG in the formulation was optimum for enhancing the drug flux across silicone membrane. FT-IR analysis confirmed absence of drug-polymer interactions. Selected optimized lotion formulation was then subjected to accelerated stability testing, sensatory perception testing and in vitro permeation across rabbit skin. The drug flux from the optimized lotion across rabbit skin was significantly better that that from the control formulation. Furthermore, sensatory perception test rated a higher acceptability while lotion was stable over stability testing period. Therefore, use of Box-Wilson statistical design successfully elaborated the influence of formulation variables on permeation of lornoxicam form topical formulations, thus, helped in optimization of the lotion formulation.