Current Issue : October - December Volume : 2011 Issue Number : 4 Articles : 12 Articles
The aim of the present investigation was to develop controlled release matrix tablet formulations of metformin hydrochloride using Chitosan and Eudragit L100 polymer alone and in combination at different concentrations and to evaluate in vitro release characteristics. Metformin HCL, a biguanide has relatively short plasma half life, low absolute bioavailability. All the batches were evaluated for thickness, weight variation, hardness, and drug content uniformity and in vitro drug release. Mean dissolution time is used to characterize drug release rate from a dosage form and indicates the drug release retarding efficiency of polymer. Hydrophilic matrix of Chitosan alone could not control the Metformin release effectively for 12 h whereas when combined with Eudragit L100 could slow down the release of drug and can be successfully employed for formulating sustained-release matrix tablets. Swelling studies were also carried out. Fitting the data to Korsmeyer equation indicated that diffusion along with erosion could be the mechanism of drug release....
Physically cross linked polymeric films containing atenolol drug were formulated and the release of the drug was evaluated with view to investigate the feasibility of these films as drug delivery systems. Freezing and thawing process for PVA was used to prepare a controlled release device for atenolol drug. The process included incorporation of the drug into PVA film during the freezing and thawing process. The PVA has used a molecular weight of 125 k and degree of saponification of 98. Various amounts of the atenolol drug were incorporated into the freeze/thawed PVA. The in vitro release behaviour of atenolol from these films was investigated. The drug release profiles from the polymeric formulations indicated initial high rate of release followed by slow rate of the release. The release of atenolol increased with increasing drug concentration in the film. The results showed the feasibility of the use of freezing and thawing technique to control the release of atenolol drug from PVA....
The aim of the present study was to produce controlled release Microsponge gels containing voriconazole with varying proportions of Eudragit RS100 and Eudragit L100 as polymers were successfully formulated using quasi-emulsion solvent diffusion method and evaluated. The scanning electron microscopy showed that they were spherical in shape and porous in nature. Physical characterization showed that formulations MSIV and MLIV showed a better loading efficiency. The formulations showed good viscosity and drug release characteristics. The antimicrobial studies showed zone of inhibition with 18.5 mm and19.0 mm for microsponge formulation gel MSIV and MLIV respectively when compared Marketed Fluconazole, zone of inhibition of 19.5mm. Fluconazole gel was used as control in our studies. In vivo studies were performed on guinea pigs. Fungal infection was induced on the skin of these animals using candida albicans. The results indicate that voriconazole when formulated as a microsponge system was capable of producing excellent antimicrobial and antifungal effect at par with conventional control gel of fluconazole. Thus voriconazole microsponges can be considered as a promising alternative in the effective treatment of fungal infections in the form of a gel for faster relief in patients suffering for invasive fungal infections...
Clarithromycin has a short elimination half-life, a narrow absorption window and is mainly absorbed in proximal areas of GIT. The purpose of this study was to develop a gastro retentive controlled release drug delivery system with swelling, floating, and mucoadhesive properties. Ten tablet formulations were designed using hydroxypropylmethylcellulose (HPMC K100M) and xanthan gum as release-retarding polymer(s) and sodium bicarbonate (NaHCO3), Sodium carbonate (NaCO3) and calcium carbonate (CaCO3) as a gas former. Swelling ability, floating behaviour, adhesion period and drug release studies were conducted in 0.1 N HCl (pH 1.2) at 37 ± 0.5º C. The tablets were subjected to various physiochemical tests, weight variation, content uniformity, thickness, hardness, floating lag time, adhesion period, total floating time etc. The study data revealed acceptable values of physicochemical properties. Drug release profiles of all formulation followed first order kinetic and diffusion mechanism. Statistical analyses of data revealed that tablets containing HPMC K100M (20% w/w), xanthan gum (5% w/w) and NaHCO3 (12%, w/w) in F8 or CaCO3 (12%, w/w) in F9 were promising systems exhibiting excellent floating properties, extended adhesion periods and sustained drug release characteristics. Both formulations were stored at 40º C/75% RH for 3 months according to ICH guidelines. Formula F10 showed better physical stability and longer release profile, so F10 was selected for the further in vivo study. Abdominal X-ray imaging of formula F10, loaded with barium sulfate, in New Zealand albino rabbit revealed a mean gastric retention period of 9.2 ± 0.51 h....
The present investigation was aimed to formulate transdermal films incorporating herbal Drug components. The allopathic system of medicine includes two conventional lines of treatment for rheumatoid arthritis, which come along with certain side effects. Hence, turning to safe, effective and time-tested Ayurvedic herbal drug formulation would be a preferable option.With this view transdermal films incorporating herbal drug cloroform extract of Trichodesma indicum and Boswellia serrata was envisaged. The drugs were selected on the basis that they produce synergistic action in suppressing inflammation and are proved time tested and safe drug. Chloroform extract of trichodesma indicum and Boswellia serrata are dissolved in chloroform and dispersed uniformly throughout the film. The film of chloroform extract of trichodesma indicm and Boswellia serrata showed a satisfactory flatness in 99.0 % and Average thickness of films was found to be 0.0085 cm . Average content of chloroform extract of trichodesma indicm and Boswellia serrata in films was found to be 78.91% and 88.72% respectively. The calibration curve of chloroform extract of trichodesma indicm and Boswellia serrata was prepared in hydroalcoholic medium using HPTLC and UV. The polymeric films were evaluated for their physical properties like percentage flatness, thickness uniformity, and drug content and diffusion studies across hairless mouse skin. The average per cent release of trichodesma indicum extract was found to be 48.70% and 69.84% for Boswellia serrata in the hydroalcoholic diffusion medium at the end of 9 hrs. The graphs obtained for the average per cent release through transdermal film indicate drug release occurred at a constant rate.The skin irritation study done on albino rabbit skin showed that the formulation does not produce irritation to the skin.Overall, it was observed that the herbal drugs have been found to be effective through modern pharmaceutical formulation techniques....
The aim of present investigation was to develop and evaluate bilayer sustained release tablets of Diltiazem hydrochloride (DTZ) .The bilayer sustained release tablets were prepared by wet granulation. Polyox WSR 303 and HPMC K15M were used as hydrophilic polymers. Superdisintegrant was incorporated into the formulations to release fastly loading dose from the dosage form. The amount of polymer blends was optimized using 32 full factorial design. The prepared bilayer tablets were evaluated for disintegration time, swelling study, hardness, friability, drug content and in-vitro release. More than 90% of Diltiazem drug was released within 1 hour. HPMC K15M and polyox WSR 303 sustained the release of Diltiazem hydrochloride from the sustained release layer for 12 hrs. Diffusion exponents (n) were determined for optimized formulation (<0.5).So, predominant drug release mechanism is Fickian diffusion mechanism. The stability study showed no significant change in appearance of tablets, drug content and dissolution profile. Therefore, biphasic drug release pattern was successfully achieved through the formulation of bilayer sustained release tablets....
Floating tablet of Torsemide (F) were prepared by direct compression technique. Torsemide was chosen as model drug because it is poorly soluble or water insoluble and poorly absorb from lower intestine. PEG-6000 is used as complexing agent for increasing solubility of Torsemide in water.Hydroxypropylmethylcellulose, sodium bicarbonate and carbapole were used as Matrixing agent gasgenerating agent and floating enhancers respectively. The tablets were evaluated for in-vitro buoyancy and dissolution studies Tablets were evaluated for physical characteristic viz. hardness, floating capacity thickness, swelling index, and weight variation. Further, tablets were evaluated for in vitro release characteristic for 8 hrs. The data of in-vitro dissolution study shows that the zero order plots were found to be fairly linear as indicated by their high regression value (R2=0.9772 to 0.9911). To confirm the exact mechanism of drug release from different formulation, the data was fitted to Korsmeyer Peppas equation. Regression values were from 0.9862 to 0.9963 which indicates linearity....
The objective of the present study was to develop an effective formulation for Ibuprofen chewable tablets with an emphasis on organoleptic properties. The methods involve coating the drug substance itself, granulating the drug and then coating these granules using substances like ethyl cellulose, hydroxy propyl methyl cellulose, Eudragit E 100, Eudragit RD 100 and granulating the drug along with Excipients like mannitol and sorbitol. To optimize the formulation, effect of various Excipients (diluents and vehicles alone & in combination), sweetening and flavoring agents on physicochemical & organoleptic properties of tablets were studied. Stability studies were carried out for finalized formulation in suitable packing like blister and strip and then keeping at different temperatures & humidity conditions for 60 days. Evaluation studies of the optimized formulation before and after stability studies showed no significant difference in drug content, drug release profiles, physicochemical and organoleptic properties indicated that an efficient taste masking formulation was developed for Ibuprofen chewable tablets....
Patented platform technologies have been used for the liposomal encapsulation of cisplatin (Lipoplatin) into tumor-targeted 110?nm (in diameter) nanoparticles. The molecular mechanisms, preclinical and clinical data concerning lipoplatin, are reviewed here. Lipoplatin has been successfully administered in three randomized Phase II and III clinical trials. The clinical data mainly include non-small-cell lung cancer but also pancreatic, breast, and head and neck cancers. It is anticipated that lipoplatin will replace cisplatin as well as increase its potential applications. For the first time, a platinum drug has shown superiority to cisplatin, at least in non-squamous non-small-cell lung cancer as reported in a Phase III study which documented a simultaneous lowering of all of the side effects of cisplatin....
Recent evidences support that leukotrienes (LTs) are important molecules in innate and also adaptive immune responses. Some features of these lipid mediators include their ability to be synthesized by a variety of cell types, their diverse antimicrobial actions, and their interactions with other important mediators. More specifically, leukotriene B4 (LTB4) displays protective effect against infections, such as fungal pneumonia, those caused by helminths and bacterial peritonitis. With respect to histoplasmosis, the fungal infection caused by Histoplasma capsulatum, our group has previously demonstrated that these mediators are the main chemoattractants involved in the cell migration induced by the fungus. Regarding new attempts to enhance host antimicrobial response against histoplasmosis, over the last years, we have proposed the employment of a biodegradable microparticulate system, which could release LTB4 to the lungs, as an alternative strategy to treat airway infectious diseases. Here we provide some studies involving the administration of this lipid mediator in several animal and human models of infection and we explore the advantages of the microencapsulated LTB4 as innovative pharmaceutical approach....
The challenge of targeting drugs specifically to the colon has been embraced by scientist over the past two decades. The colon has recently become accepted as an increasingly accepted site for drug delivery. Till date necessity and advantages of colon-specific drug delivery systems have been well recognized and documented. In the past, the primary approaches to obtain colon-specific delivery achieved limited success and included prodrugs, pH- and time-dependent systems, pressure and microflora-activated systems. Precise colon drug delivery requires that the triggering mechanism in the delivery system only respond to the physiological conditions particular to the colon. Hence, continuous efforts have been focused on designing colon-specific delivery systems with improved site specificity and versatile drug release kinetics to accommodate different therapeutic needs. Among the systems developed most recently for colon-specific delivery, four systems were unique in terms of achieving in vivo site specificity, design rationale, and feasibility of the manufacturing process (pressure-controlled colon delivery capsules (PCDCs), CODES™, colonic drug delivery system based on pectin and galactomannan coating, and Azo hydrogels). The focus of this review is to provide detailed descriptions of the four systems, in particular, and in vitro/in vivo evaluation of colon-specific drug delivery systems, in general....
A summary provides a synopsis of those issues and concludes that the complex technical nature of pharmaceutical development and manufacturing offers many opportunities for the effective use of statistical and optimization thinking and methods. The pharmaceutical industries undergoing rapid change and facing numerous challenges including the demand of global competition, the need to speed up the drug development process. The FDA’s expectation for submission of new drug or new dosage forms. Statistical input in sampling and testing for quality control, stability testing ,process validation design of preclinical protocol including statistical methods and appropriate statistical analysis of resulting data , are application routinely applied by pharmaceutical industries to satisfy both internal requirement and FDA’s recommendation . Statistical thinking and methods plays significant role in addressing these issues. This article provides an overview of the use of statistical thinking and techniques in manufacturing function of the pharmaceutical industries. The exposition includes the various techniques by which one may effectively treat the scientific data normally obtained in actual analytical procedure....
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