Influence of Prunus domestica gum on the release profiles of propranolol HCl floating tablets.

Propranolol hydrochloride is a beta-blocker used for the management and treatment of hypertension, angina, coronary artery disease, heart failure, fibrillation, tremors, migraine etc. The objective of the present study was to design Propranolol Hydrochloride floating tablets by direct compression method and to explore the role of a new gum as a matrix former. A 22 full factorial design was selected for the present study. Prunus domestica gum and HPMC (K4M) were used as independent variables, swelling index and drug dissolution at 12 hours as dependent variables. Formulations were subjected to pre- and post-compression tests that showed good micromeritics and buoyancy characteristics (Carr's index 11.76%-14.00%, Hausner's ratio 1.13°-1.16°, angle of repose 22.67°-25.21°, floating lag time 56-76 seconds, total floating time 18-25 hours and swelling index 59.87%-139.66%). The cumulative drug release in 0.1 N HCl at 12 hours was 72%-90% (p<0.05). Weibull model was found to be the best fit model (R2>0.99) among all other studied models. Multiple regression showed a significant effect of Prunus domestica gum and HPMC K4M on the swelling index and dissolution profiles of propranolol HCl (p<0.05). On the basis of better in-vitro performance and cost-effectiveness, formulation F4 was the best formulation. It is evident from the results that Prunus domestica gum possesses excellent drug release retardant potential for the floating drug delivery system and this new gum should be further explored alone or with other natural and synthetic polymers in future studies.

Possibility of extending biopharmaceutics classification system based biowaiver to BCS class IIa drug.

Biowaiver studies have been performed to assess the bioequivalence of two drug products. Ibuprofen is a Biopharmaceutics Classification System (BCS) class IIa drug (Low solubility - High permeability) used as analgesic, antipyretic and anti-inflammatory agent. World Health Organization (WHO) placed ibuprofen in the category of biowaiver drugs but Food and drug authority (FDA) and International Council for Harmonization (ICH) has not issued yet any guidelines regarding the biowaiver of BCS class II drugs. Present study was aimed to formulate immediate release (IR) Ibuprofen 600 mg tablets with variable disintegrants. All trial film coated formulations were evaluated physicochemically with in-vitro bioequivalence studies in three buffer mediums (pH 6.8, pH 4.5 and pH 1.2). Samples were analyzed spectrophotometrically at 221 nm and model independent approaches (dissimilarity (f1), similarity (f2;) and Boot strap) was applied to assess the observed similarity. The similarity factor (f2;) was achieved only in pH 1.2 in three trial formulations and met acceptance criteria (f2; 50-100) although the amount of drug release was negligible. This investigation revealed that for BCS class IIa drug (ibuprofen), subsequent analysis of excipients used, pKa of drug and method of manufacturing should also be considered to ensure bioequivalence for a successful biowaiver study.

Impact of different organic acids on solubility enhancement of cefpodxime proxetil immediate release tablet and its stability studies.

Cefpodoxime proxetil is a third generation cephalosporin antibiotic demonstrates pH dependent solubility and is highly soluble only in acidic pH. The purpose of this investigation was to design and develop immediate release tablets of cefpodoxime proxetil by direct compression method and determine the effect of different solid buffers (organic acids) such as fumaric acid (formulations F1-F4), maleic acid (formulations M1-M4) and citric acid (formulations C1-C4) by using cefpodoxime and acid in the ratios of 4:1, 2:1, 1:1 and 1:2 to achieve pH-independent release of the drug. Physical parameters and assay were found to be within the acceptable range as prescribed in USP 36 / NF 31. In vitro dissolution studies of each formulation were performed in distilled water, USP dissolution medium, HCl buffer solution of pH 1.2, phosphate buffer solutions of pH 4.5 and 6.8 to observe the drug release. The formulations F3, F4, M4 were selected for film coating on the basis of better drug release profile, to protect the drug from chemical degradation through hydrolysis. Film coated formulation F3, F4 and M4 showed a remarkable in vitro release of the drug (72.88±0.43 to 92.67±0.71%) within 30min of observation in all dissolution media and further evaluated by model independent and model dependent approaches. The drug release was found to be best fit to Weibull model as highest r2adjusted (0.924-0.998) and lowest AIC (18.416-54.710) values were obtained in all dissolution media. R Gui® applied for stability studies of F3 and F4 formulations, showing shelf lives of 28 & 27months at ambient and 33 months at accelerated temperatures. Formulation F4 was chosen as best formulation on the basis of physical properties, highest dissolution rate and stability studies.

Formulation and Dissolution enhancement of Meloxicam tablets using Polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer and Povidone in combination.

Meloxicam is a poor water soluble drug mostly prescribed in various rheumatic diseases. The present research study was design to formulate and increase the solubility of meloxicam in the tablet dosage form. A 32 full factorial design was employed to optimize meloxicam formulations. Polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol graft copolymer (PVCL-PVA-PEG graft copolymer) and Povidone were taken as independent variables while cumulative drug release at 90 minutes was selected as dependent variable. All trial formulations complied with official standards. Multiple regression by Microsoft Excel on cumulative drug release of the selected formulations (F1, F2, F6- F9) showed the positive effect of PVCL-PVA-PEG graft copolymer (α = 0.05) and a negative effect of Povidone (α = 0.05). Formulation six (F6) (PVCL-PVA-PEG graft copolymer 3 mg and Povidone 22.5 mg / tablet) was considered as the optimal formulation based on its cumulative drug release. Dissolution kinetics by model dependent analysis predicted Weibull (R2=0.99) as the best fit model in describing meloxicam dissolution kinetics. The role of PVCL-PVA-PEG graft copolymer should be explored with other solubilizers in future studies.

Short Communication: Perception and attitude of pharmacy students towards learning tools.

Use of technology in education has increased worldwide. Teaching methodologies are shifting from traditional classroom lectures to e-learning and computer-based learning. Pakistani students are also now fathoming necessity of acquiring tools for strengthening their knowledge and skills. The objective of present study was to analyze the shifting trends (perception and attitudes) of Pakistani Pharmacy students towards learning tools. A survey based study conducted on 296 students from various years of Pharmacy, studying in a state owned university, Karachi, Pakistan. This study was initially piloted and Cronbach's-alpha was computed for evaluation of internal consistency of questionnaire (for perception; 0.660, for attitude; 0.777 respectively). Data was computed by SPSS, version 16 (Crosstab) and Chisquare (P=0.05). Most of the students strongly agreed (53%; χ² =495;P<0.05) that introducing technology will improve learning; books are reliable reading source (53%; χ² =437.23; P<0.05) or book-reading is essential (50%; χ² =360.36; P<0.05) while others disagreed that they only study from class lectures (31%; χ² =17.22; P<0.05); not take classes (41%; χ² =48.21; P<0.05); have used software (44%; χ² =46.54; P<0.05). Majority of the students agreed on incorporating technology to improve learning. Other factors such as unavailability and expenditure of books influenced their ability to learn. This study might assist policy makers in developing policies that could improve learning.

Formulation and stability evaluation of immediate release antioxidant tablet.

Oxidative stress plays an important part in the development of human diseases. Pharmaceutical strategies are required to be work out in order to fight against such oxidative damages. Designing of new formulations that can protect human beings from the undesirable effects, consequence of oxidative stress, the crucial cellular and molecular processes, along with recurring oxidative damage and diseases is to be expedited. The main objective of present work was to design a rapidly releasing synthetic antioxidant tablet dosage form comprising of vitamin A, vitamin C, vitamin E and zinc in combination with lecithin (a phospho-lipid) that can fulfill human health and nutritional requirement and to perform stability studies. Beside active ingredients, the excipients used in present formulation were; Avicel pH 102, starch pregelatinized, silicon dioxide colloidal and polyethylene glycol 8000 milled magnesium stearate, acid stearic fine powder and aq.opa dry coating material. The immediate release formulation of antioxidant was prepared by wet granulation method. Three different trials were developed. Vitamin C was selected as tracer for detection and evaluation of tablet dosage form. When the resulting formulation was evaluated by USP 24 / NF 19, 2000 guidelines and later by stability studies, it was found that their quality can be maintained over a storage period of 24 months.

Formulation design and evaluation of Cefuroxime axetil 125 mg immediate release tablets using different concentration of sodium lauryl sulphate as solubility enhancer

Cefuroxime axetil immediate release tablets were formulated by direct compression method with different percentages of sodium lauryl sulphate (SLS) such as 0.5, 1.0, 1.5 and also without SLS. Resulting batches of tablets were evaluated by both pharmacopeial and non-pharmacopeial methods to ascertain the physico-mechanical properties. Dissolution test were carried out in different medium like 0.07 M HCl, distilled water, 0.1M HCl of pH 1.2 and phosphate buffers at pH 4.5 and 6.8 to observe the drug release against the respective concentration of SLS used. Later, test formulations were compared by f1 (dissimilarity) and f2 (similarity) factors using a reference brand of cefuroxime axetil. Significant differences (p<0.05) in dissolution rate were recorded with the change in concentration of SLS in different media. Test formulation T3 containing 1% SLS was found to be best optimized formulation based on assay, disintegration, dissolution and similarity and dissimilarity factors.

Formularam-se comprimidos de liberação imediata à base de cefuroxima axetil, pelo método de compressão direta, com diferentes percentagens de lauril sulfato de sódio (LSS), tais como 0,5, 1,0, 1,5, e também sem SLS. Os lotes resultantes dos comprimidos foram avaliados por ambos os métodos da farmacopeia e não farmacopeicos para determinar as propriedades físico-mecânicas. O teste de dissolução foi realizado em meios diferentes, como HCl 0,07 M, água destilada, HCl 0,1 M com pH 1,2 e os tampões fosfato (pH 4,5 e 6,8) para observar a liberação do fármaco contra a correspondente concentração de LSS utilizado. Em seguida, as formulações de teste foram comparadas por fatores f1 (dissimilaridade) e f2 (similaridade), utilizando uma marca de referência de cefuroxima axetil. Diferenças significativas (p<0,05) na taxa de dissolução foram registradas com a mudança na concentração de LSS em diferentes meios de dissolução. A formulação T3 contendo LSS a 1% foi considerada a melhor formulação otimizada com base nos ensaios de desintegração, dissolução e fatores de semelhança e dissimilaridade.

Antibacterial activity of Phyllantus emblica, Coriandrum sativum, Culinaris medic, Lawsonia alba and Cucumis sativus.

Present study deals with the demonstration of the antibacterial activity of very common medicinal plants of Pakistani origin i.e., Phyllantus emblica, Coriandrum sativum, Culinaris medic, Lawsonia alba and Cucumis sativus. The extracts were prepared in crude form by the use of hydro-alcoholic solution and were screened for antibacterial activity against various bacterial species by disk diffusion method. Assay was performed using clinical isolates of B. cereus, S. aureus, P. aeruginosa and E. coli. Crude extract of Phyllantus emblica fruit exhibited strong activity against standard cultures of all studied bacteria. Lawsonia alba showed good activity against standard cultures of all the used microorganisms. Coriandrum sativum was effective only against Bacillus cereus, while Cucumis sativus and Culinaris medic showed poor activity against Pseudomonas aeruginosa only. Hence, Phyllantus emblica exhibited strong antibacterial activity against a wide range of bacteria it means that Phyllantus emblica extract contains some compounds which have broad spectrum of bactericidal activity.

Physico-chemical comparison of famotidine tablets prepared via dry granulation and direct compression techniques.

Famotidine is generally employed for the treatment of gastric ulcer. The present study was conducted to fabricate famotidine tablets using various diluents. The binder was incorporated to the formulations in different proportions. Both the dry granulation and direct compression techniques were employed to develop the tablets. Physical evaluation of tablets i.e. tablets hardness, friability, weight variation, thickness and diameter was determined. In vitro dissolution studies of the prepared tablets were carried out for 60 min using the USP apparatus II and 900 ml 0.1 M HCl stirred at 37 ± 0.5°C with a speed of 50 rpm. Physical analysis of tablets prepared via direct compression showed satisfactory results regarding the weight variation, hardness and friability, since their respective values were within the BP limits. All the prepared famotidine tablets exhibited diffusion based mode of drug release. 100% release of drug occurred in less than 60 min. The drug release from all the formulated tablets has elaborated the involvement of diffusion (Higuchian drug release). This comparative study exhibited that physical parameters of tablets are affected by the technique of tabletting.

Report: Studies on antibacterial activity of some traditional medicinal plants used in folk medicine.

Ethanolic extracts of eight medicinal plants commonly used in folk medicine were tested for their antibacterial activity against four Gram positive strains (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis and, Streptococcus pneumoniae) and six Gram negative strains (Escherichia coli, Proteus vulgaris, Proteus mirabilis. Salmonella typhi para A, Salmonella typhi para B and Shigella dysenteriae) that were obtained from different pathological laboratories located in Karachi, Pakistan. Disc diffusion method was used to analyze antibacterial activity. Out of eight, five medicinal plants showed antibacterial activity against two or more than two microbial species. The most effective antimicrobial plant found to be Punica granatum followed by Curcuma zedoaria Rosc, Grewia asiatica L and Carissa carandas L, Curcuma caesia Roxb respectively. From these results, it is evident that medicinal plants could be used as a potential source of new antibacterial agents.

Antimicrobial activity of erythromycin and clarithromycin against clinical isolates of Escherichia coli, Staphylococcus aureus, Klebsiella and Proteus by disc diffusion method.

Fifty clinical isolates comprising of Escherichia coli, Staphylococcus aureus, Klebsiella and Proteus were collected from different local pathological laboratories and their resistant pattern against two well known macrolides; erythromycin and clarithromycin were studied using disc diffusion method. Klebsiella (41.67% against erythromycin and 58.34% against clarithromycin) and Proteus (66.67% against erythromycin and clarithromycin) species were found to be more resistant against the studied macrolides as compared to the rest of organisms. In case of Staphylococcus aureus and Escherichia.coli, resistant found were 27.78% and 23.54% against erythromycin and 22.23% and 35.30% against clarithromycin respectively. It is concluded from these figures that microbial resistance against these macrolides are increasing in our population which is alarming and therefore it is recommended to physicians to prescribe these antibiotics unless no other substitute is available in clinical practices.

Studies of food drug interactions.

Medicines can treat and alleviate many diseases provided that they must be taken properly to ensure that they are safe and useful. One issue related with the medicines is that whether to take on empty stomach or with food. The present work gives information regarding food-drug interactions that were studied by collecting seventy five prescriptions from various hospitals. In most of the collected prescriptions, food-drug interactions were detected using the literature available. It was also found that only few studies have been carried out so far on the effect of food on drug disposition in the Asian population. Thus more studies on food-drug interactions particularly in the local population is recommended in order to determine the effect of food and food components on drug disposition and to the kinetics of the drugs which has not yet well highlighted in this part of the world.

Bioequivalence studies of two brands of meloxicam tablets in healthy Pakistani volunteers.

The pharmacokinetic parameters of two oral formulations of meloxicam tablets were compared in a randomized, single oral dose; two treatments cross over design in 12 healthy male volunteers belonging to Pakistan under fasting conditions. After an overnight fast, the volunteers received 30 mg meloxicam and the blood samples were collected up to 96 hours and drug concentrations were determined by a validated HPLC method. Various pharmacokinetic parameters were determined from the plasma concentration-time curves of both formulations. The 90% confidence intervals obtained by analysis of variance were 87-94% for C(max) and 88-97% for AUC(0-t), that fell well within the acceptance range of 80-125%. Also, no significant difference (a=0.05, Wilcoxon Signed rank test) were detected between T(max) of both formulations. The two formulations were well tolerated and no adverse effect was reported during the study.