Advances in Pharmaceutics The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Preliminary Investigation of Bioactive Compounds and Bioautographic Studies of Whole Plant Extract of Euphorbia pulcherrima on Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa Wed, 21 Jan 2015 09:01:16 +0000 The aim of this study is to carry out preliminary investigation of bioactive compounds and bioautographic studies of whole plant extract of Euphorbia pulcherrima on Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa. Tukey HSD test of hierarchy for the effect of different solvents crude extract on bacterial isolates indicates the methanol extract as the most bioactive. The Tukey HSD analysis also showed that the bioactivities of the crude extracts of the various parts of Euphorbia pulcherrima were part dependent and the whole plant was the most bioactive. The ethyl acetate fraction of the methanol extract of the whole plant of Euphorbia pulcherrima has been shown in this work to contain phytochemicals which have shown remarkable activities against Escherichia coli, Staphylococcus aureus, Salmonella typhi, and Pseudomonas aeruginosa. The bioactivities against the test organisms were due to the combined effects of the compounds separated on TLC plates. Families of terpenoids, flavonoids, alkaloids, saponin, and steroids that were detected in the extracts were identified by GC-MS. The various classes of phytochemicals in the E. pulcherrima plant provided the antimicrobial potency of the plant. H. B. Sharif, M. D. Mukhtar, Y. Mustapha, and A. O. Lawal Copyright © 2015 H. B. Sharif et al. All rights reserved. Unstirred Water Layer Effects on Biodegradable Microspheres Mon, 12 Jan 2015 07:13:32 +0000 This study explores the mechanistic aspects of in vitro release from biodegradable microspheres with the objective of understanding the effect of the unstirred water layer on polymer degradation and drug release. In vitro drug release experiments on Leuprolide PLGA microspheres were performed under “static” and “continuous” agitation conditions using the “sample and separate” method. At specified time intervals, polymer degradation, mass loss, and drug release were assessed. While molecular weight and molecular number profiles for “static” and “continuous” samples were indistinct, mass loss occurred at a faster rate in “continuous” samples than under “static” conditions. In vitro results describe a fourfold difference in drug release rates between the “continuous” and “static” samples, ascribed to the acceleration of various processes governing release, including elimination of the boundary layer. The findings were confirmed by the fourfold increase in drug release rate when “static” samples were subjected to “continuous” agitation after 11 days. A schema was proposed to describe the complex in vitro release process from biodegradable polymer-drug dosage forms. These experiments highlight the manner in which the unstirred water layer influences drug release from biodegradable microspheres and stress the importance of selecting appropriate conditions for agitation during an in vitro release study. Susan D’Souza, Jabar A. Faraj, and Patrick P. DeLuca Copyright © 2015 Susan D’Souza et al. All rights reserved. Development and Validation of Acyclovir HPLC External Standard Method in Human Plasma: Application to Pharmacokinetic Studies Wed, 31 Dec 2014 07:51:33 +0000 A simple, rapid, and selective RP-HPLC method was developed for the estimation of acyclovir in human plasma. The method involves a simple protein precipitation technique. Chromatographic separation was carried out on a reverse phase C18 column using mixture of 5 mM ammonium acetate (pH 4.0) and acetonitrile (40 : 60, v/v) at a flow rate of 1.0 mL/min with UV detection at 290 nm. The retention time of acyclovir was 4.12 minutes. The method was validated and found to be linear in the range of 25.0–150.0 ng/mL. Validation studies were achieved by using the fundamental parameters, including accuracy, precision, selectivity, sensitivity, linearity and range, stability studies, limit of detection (LOD), and limit of quantitation (LOQ). It shows recovery at 91.0% which is more precise and accurate compared to the other method. These results indicated that the bioanalytical method was linear, precise, and accurate. The new bioanalytical method was successfully applied to a pharmacokinetic linearity study in human plasma. Selvadurai Muralidharan, Jayarajakumar Kalaimani, Subramani Parasuraman, and Sokkalingam Arumugam Dhanaraj Copyright © 2014 Selvadurai Muralidharan et al. All rights reserved. Nanoemulsion Based Hydrogel for Enhanced Transdermal Delivery of Ketoprofen Tue, 16 Dec 2014 13:43:25 +0000 The aim of the present study was to investigate the nanoemulgel as transdermal delivery system for poorly water soluble drug, ketoprofen, in order to overcome the troubles associated with its oral delivery. Different nanoemulsion components (oil, surfactant, and cosurfactant) were selected on the basis of solubility and emulsification ability. Pseudoternary phase diagrams were constructed using titration method to figure out the concentration range of components. Carbomer 940 was added as gel matrix to convert nanoemulsion into nanoemulgel. Drug loaded nanoemulsions and nanoemulgels were characterized for particle size, TEM, viscosity, conductivity, spreadability, rheological behavior, and permeation studies using Wistar rat skin and stability studies. Transdermal permeation of ketoprofen from nanoemulgels was determined by using Franz diffusion cell. Nanoemulgel containing 6% oleic acid as oil, 35% Tween 80, and Transcutol P as surfactant cosurfactant mixture, 56.5% water, 2.5% drug, and 0.6% carbomer was concluded as optimized formulation (NG6). The ex vivo permeation profile of optimized formulation was compared with nanoemulsion and marketed formulation (Fastum). Nanoemulgel showed significantly higher () cumulative amount of drug permeated and flux along with lower lag time and skin retention than marketed formulation. Thus, the study substantiated that nanoemulgel formulation can be used as a feasible alternative to conventional formulations of ketoprofen with advanced permeation characteristics for transdermal application. Ritika Arora, Geeta Aggarwal, S. L. Harikumar, and Kirandeep Kaur Copyright © 2014 Ritika Arora et al. All rights reserved. A Review of In Vitro Drug Release Test Methods for Nano-Sized Dosage Forms Thu, 20 Nov 2014 07:14:38 +0000 This review summarizes the methods used to study real-time (37°C) drug release from nanoparticulate drug delivery systems and establish an IVIVC. Since no compendial standards exist, drug release is currently assessed using a variety of methods including sample and separate (SS), continuous flow (CF), dialysis membrane (DM) methods, and a combination thereof, as well as novel techniques like voltametry and turbidimetry. This review describes the principle of each method along with their advantages and disadvantages, including challenges with set-up and sampling. The SS method allows direct measurement of drug release with simple set-up requirements, but sampling is cumbersome. With the CF method, sampling is straightforward but the set-up is time consuming. Set-up as well as sampling is easier with the DM, but it may not be suitable for drugs that bind to the membrane. Novel methods offer the possibility of real-time drug release measurement but may be restricted to certain types of drugs. Of these methods, Level A IVIVCs have been obtained with dialysis, alone or in combination with the sample and separate technique. Future efforts should focus on developing mathematical models that describe drug release mechanisms as well as facilitate formulation development of nano-sized dosage forms. Susan D’Souza Copyright © 2014 Susan D’Souza. All rights reserved. Pharmacodynamics and Pharmacokinetics Evaluation of Ranitidine Microemulsion on Experimental Animals Mon, 20 Oct 2014 11:32:30 +0000 Ranitidine microemulsion was investigated for its pharmacodynamic and pharmacokinetic evaluation to find out the suitability of microemulsion as a potential drug delivery system in the treatment of ulcer. The bioavailability of ranitidine after oral administration is about 50% and is absorbed via the small intestine; this may be due to low intestinal permeability. Hence the aim of present investigation was to maximize the therapeutic efficacy of ranitidine by developing microemulsion to increase the intestinal permeability as well as bioavailability. A ground nut oil based microemulsion formulation with Tween-80 as surfactant and PEG-400 as cosurfactant was developed for oral delivery of ranitidine and characterized for physicochemical parameters. In pharmacodynamic studies, significant () variation in parameters estimated was found between the treated and control groups. Ranitidine microemulsion exhibited higher absorption and Cmax (863.20 ng·h/mL) than the standard (442.20 ng/mL). It was found that AUC0–24 hr obtained from the optimized ranitidine test formulation (5426.5 ng·h/mL) was significantly higher than the standard ranitidine (3920.4 ng·h/mL). The bioavailability of optimized formulation was about 1.4-fold higher than that of standard drug. This enhanced bioavailability of ranitidine microemulsion may be used as an effective and alternative drug delivery system for the antiulcer therapy. Sajal Kumar Jha, Roopa Karki, Venkatesh Dinnekere Puttegowda, and Amitava Ghosh Copyright © 2014 Sajal Kumar Jha et al. All rights reserved. Lipid Based Vesicular Drug Delivery Systems Tue, 02 Sep 2014 12:31:39 +0000 Vesicular drug delivery system can be defined as highly ordered assemblies consisting of one or more concentric bilayers formed as a result of self-assembling of amphiphilic building blocks in presence of water. Vesicular drug delivery systems are particularly important for targeted delivery of drugs because of their ability to localize the activity of drug at the site or organ of action thereby lowering its concentration at the other sites in body. Vesicular drug delivery system sustains drug action at a predetermined rate, relatively constant (zero order kinetics), efficient drug level in the body, and simultaneously minimizes the undesirable side effects. It can also localize drug action in the diseased tissue or organ by targeted drug delivery using carriers or chemical derivatization. Different types of pharmaceutical carriers such as polymeric micelles, particulate systems, and macro- and micromolecules are presented in the form of novel drug delivery system for targeted delivery of drugs. Particulate type carrier also known as colloidal carrier system, includes lipid particles, micro- and nanoparticles, micro- and nanospheres, polymeric micelles and vesicular systems like liposomes, sphingosomes, niosomes, transfersomes, aquasomes, ufasomes, and so forth. Shikha Jain, Vikas Jain, and S. C. Mahajan Copyright © 2014 Shikha Jain et al. All rights reserved. Prophylactic Effects of Ethanolic Extract of Irvingia gabonensis Stem Bark against Cadmium-Induced Toxicity in Albino Rats Mon, 01 Sep 2014 00:00:00 +0000 The prophylactic effect of ethanolic extract of Irvingia gabonensis stem bark on cadmium-induced oxidative damage in male albino rats’ liver was investigated. Male Wistar rats were divided into control, cadmium, and treatment groups. In the prophylactic experiment, Irvingia gabonensis (200 and 400 mg/kg body weight) was administered by oral gavage for 21 days before exposure to cadmium. Antioxidant marker enzymes such as reduced glutathione (GSH) levels, catalase (CAT), glutathione peroxidase (GPx), superoxide dismutase (SOD), and lipid peroxidation (LPO) were determined in the liver and heart alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities were monitored and histological examination was carried out. Results indicate that cadmium-induced rats had significantly increased relative weight of liver and heart when compared to controls. Treatment with Irvingia gabonensis at 200 and 400 mg/kg caused a significant decrease in relative weight of the organs. In cadmium-induced rats, serum ALT and AST activities and levels of LPO were increased whereas hepatic and cardiac marker enzymes significantly decreased. Furthermore, histological alteration in liver and aorta was observed in cadmium untreated rats and was ameliorated in cadmium rats treated with Irvingia gabonensis. In conclusion, the extract indicates antioxidant and hepatoprotective properties that eliminate the deleterious effects of toxic metabolites of cadmium. Oluwafemi Adeleke Ojo, Basiru Olaitan Ajiboye, Babatunji Emmanuel Oyinloye, and Adebola Busola Ojo Copyright © 2014 Oluwafemi Adeleke Ojo et al. All rights reserved. Evaluating the Effect of Gamma Radiation on the Total Phenolic Content, Flavonoids, and Antioxidant Activity of Dried Pleurotus ostreatus ((Jacq. ex. Fr) Kummer) Stored in Packaging Materials Sun, 24 Aug 2014 07:20:31 +0000 Dried Pleurotus ostreatus mushrooms stored in polythene and polypropylene packs were exposed to gamma radiation from a cobalt-60 source at doses of 0, 0.5, 1, 1.5, and 2 kGy at a dose rate of 1.7 kGy/hr and stored for a period of 1 month. Total phenolic contents, flavonoids, and free radical scavenging activity DPPH (2,2′-diphenyl-1-picrylhydrazyl) were determined using aqueous, ethanol, and methanol extracts by Folin-Ciocaultaeu method as a source of potential natural antioxidants. Total phenol content ranged 0.56 ± 0.01–10.96 ± 1.7 mg/GAE, flavonoids ranged 1.64 ± 0.05–8.92 ± 0.6 mg/QE, DPPH radical scavenging activity also ranged 7.02 ± 0.10–13.03 ± 0.04%, and IC50 values also ranged 0.08–0.16 mg/mL. Statistical differences (P < 0.05) were recorded for the extracts and the treatment doses of mushrooms stored in polythene and polypropylene packs. A significant linear correlation was confirmed between values for the total phenolic content and antioxidant activity of mushroom extracts. The high contents of phenolic compounds indicated that these compounds contribute to high antioxidant activity. Pleurotus ostreatus can be regarded as a promising candidate for natural mushroom sources of antioxidants with high value. The use of low dose gamma radiation by the local food industry could improve the hygienic quality, extend shelf-life, and preserve nutrients and antinutrients. Nii Korley Kortei, George Tawia Odamtten, Mary Obodai, Victoria Appiah, Felicia Akuamoa, Afua Kobi Adu-Bobi, Sylvester Nana Yao Annan, Jonathan Nii Okai Armah, and Stanley Akwesi Acquah Copyright © 2014 Nii Korley Kortei et al. All rights reserved. A Rapid, Isocratic HPLC Method for Determination of Insulin and Its Degradation Product Wed, 23 Jul 2014 00:00:00 +0000 This paper aimed to develop a simple, sensitive, and rapid chromatographic procedure for the simultaneous analysis of human insulin and its main decomposition product using isocratic RP-HPLC/UV. A column type RP-C18 (100 × 4.6 mm, 3 μm particle size, and pore size 130 Å) was used. o-Nitrophenol was used as internal standard. The eluent consists of 62% KH2PO4 buffer (0.1 M), 26% ACN, and 12% MeOH. The final pH was adjusted to 3.1. The eluent was pumped at a flow rate of 1.0 mL/min and the effluent was monitored using DAD detector at 214 nm. The method produces a linear response over the concentration range of 0.0106 to 0.6810 mg/mL with detection limit of 0.0029 mg/mL. Considering the specifications of this method, the system was found to be suitable for rapid, direct routine analysis and stability studies of insulin. Ahmad Najjar, Mahmoud Alawi, Najiah AbuHeshmeh, and Alsayed Sallam Copyright © 2014 Ahmad Najjar et al. All rights reserved. In Vitro Characterization of Six Month Dosage Forms for a GnRH Antagonist Tue, 15 Jul 2014 06:51:39 +0000 The objective of this study was to develop long-acting injectable dosage forms of Orntide, a peptide GnRH antagonist, to provide tailored release for 6-month duration. Using a polylactide homopolymer and the solvent extraction/evaporation method, three microsphere formulations (Formulations A, B, and C) were prepared at various drug loadings (11.85–15.79%). The microspheres were characterized for particle size by laser diffractometry, surface morphology by scanning electron microscopy (SEM), and bulk density by tapping, as well as long-term in vitro drug release, mass loss and hydration at 37°C, and short-term in vitro drug release at elevated temperatures (51–59°C). Experiments at 37°C revealed that drug release was triphasic and occurred due to slow degradation of the polylactide polymer. Short-term in vitro release results indicated that drug release was diffusional. Application of the Higuchi equation to short-term release confirmed the temperature dependency of the diffusional rate constant. Using the rate constant and the Arrhenius equation, an value of 45 kcal/mol (Formulation A) and approximately 25 kcal/mol (Formulations B and C) was obtained for diffusional release. Study results suggest that by selection of an appropriate biodegradable polymer, injectable dosing forms that release drug for 6 months or longer can be developed. Susan D’Souza, Santos Murty, Jabar A. Faraj, and Patrick P. DeLuca Copyright © 2014 Susan D’Souza et al. All rights reserved. Rejuvenating of Kidney Tissues on Alloxan Induced Diabetic Mice under the Effect of Momordica charantia Sun, 15 Jun 2014 12:59:44 +0000 Diabetes mellitus is a chronic disorder in human and responsible for different complications and also causes mortality and morbidity. A wide number of herbal products are employed in the treatment of diabetes for their better efficacy and safety compared to synthetic medicine. The present studies have established the antidiabetic potential and rejuvenating capacity of kidney tissues under the effect of extract. Diabetes was induced in the Swiss albino mice by injecting alloxan at the dose of 150 mg/kg body weight and aqueous extract of Momordica charantia fruits at doses of 100 mg/kg body weight and 250 mg/kg body weight was administered orally for three weeks. After 21 days of treatment of the aqueous extracts of Momordica charantia significantly reduces serum glucose level, kidney function tests, lipid peroxidation as well as histopathological study also did show adverse alternation in the morphological architecture of the kidney tissue. Thus, from this study we concluded that Momordica charantia exhibited significant antihyperglycemic and rejuvenating capacity of kidney tissues activities in alloxan induced diabetic mice. Bhaskar Sharma, Mohd. Sufiyan Siddiqui, Gurudayal Ram, Ranjeet Kumar Yadav, Arti Kumari, Gaurav Sharma, and Nakuleshwar Dut Jasuja Copyright © 2014 Bhaskar Sharma et al. All rights reserved.