|1||Formulation and Evaluation of Stavudine Loaded Polymethacrylic Acid Nanoparticles |
Mallamma.T. Dr. Bharathi D.R., R. Yogananda, G. Lakshmi Radhika , Vyjayanthimala T.
Abstract: Nanoparticles represent a promising drug delivery system of controlled and targeted drug release. They are specially designed to release the drug in the vicinity of target tissue. The aim of this study was to prepare and evaluate polymethacrylic acid nanoparticles containing stavudine in different drug to polymer ratio by nanoprecipitation method to be 121 + 8 to 403 + 4 nm. The particle size of the nanoparticles was gradually increased with increase in the proportion of polymethacrylic acid polymer. The drug content of the nanoparticles was increasing on increasing polymer concentration up to a particular concentration. No appreciable difference was observed in the extent of degradation of product during 60 days in which, nanoparticles were stored at various temperatures. FT-IR studies indicated that there was no chemical interaction between drug and polymer and stability of drug. The in-vitro release behavior from all the drug loaded batches was found to be zero order and provided sustained release over a period of 24 h. The developed formulation overcome and alleviates the drawbacks and limitations of stavudine sustained release formulations and could possibility be advantageous in terms of increased bioavailability of stavudine.
Keywords: nanoparticles, stavudine, biodegradable, polymethacrylic acid.
|2||Formulation and Evaluation of Atenolol and Indapamide SR Matrix Tablet for Treatment of Hypertension |
Sarika Pundir, Ashutosh Badola
Abstract: In the present study we have formulated (f1 to f6) matrix tablets of Atenolol and Indapamide for the management of hypertension. As in simultaneous estimation of these drugs it was found that a confined release can be formulated. In the formulation of SR matrix tablet by using different concentration of delayed release agent DCP and pregelatinised starch as disintegrant we prepared tablets by wet granulation method. For sustained release action HPMC polymers were used for film coating. Preformulation studies were performed prior to compression. The compressed SR matrix tablets were evaluated for weight variation, hardness, friability, drug content, disintegration time and invitro drug release using USP dissolution apparatus type 2 (paddle). It was found that the optimized formulation showed 49.33%, 48.90%, 48.52%, 47.65%, 46.84% and 46.51% release for Atenolol in 12 hours respectively. However, Indapamide released 49.62%, 49.39%, 48.72%, 48.27%, 47.59% and 47.36% at the end of 12hrs. The IR spectrum study revealed that there is no disturbance in the principal peaks of pure drugs Atenolol and Indapamide. This confirms the integrity of pure drugs and no incompatibility of them with excipients. The stability studies were carried out for the optimized batch for one months and it showed satisfactory results. The kinetic studies of the formulations revealed that diffusion is the predominant mechanism of drug and release follows Zero order, Super case II transport.
Keywords: DCP, starch, HPMC, Atenolol, Indapamide, Zero order, simultaneous estimation.
|3||Evaluation of Phytochemical Screening and Antimicrobial Activities of Ethanolic Extracts of Leaves and Bark of Ardisia Colorata |
Easin Syed, Benyamin Mashroor, Fouad Md. Delwar Hossain, Natik Bi-Illah, Dr. Rajib Bhattacharjee, Dr. JMA Hannan
Abstract: The Ardisia colorata is one of the rare hill-tract plants in Bangladesh. The experimental research was intended to evaluate the phytochemical and antimicrobial activity of 70% ethanolic extract of leaves and bark of Ardisia colorata. Preliminary phytochemical screening of both the leaf and bark extract revealed the presence of various classes of compounds such as saponins, reducing sugars, tannins, and terpenoids with minor presence of alkaloid and flavonoid. When antimicrobial study was carried out against 10 different strains of microorganisms by detecting the zone of inhibition with disc diffusion technique, the two extracts showed very strong effect especially against Vibrio parahemolyticus and Bacillus subtilis with trace activity against Salmonella typhi. When further quantitative estimation was carried out using Minimum Inhibitory Concentration (MIC) with alternate methodology involving incorporation of phenol red indicator, their corresponding MIC numerical values were deduced at 3mg/ml respectively.
Keywords: Ardisia colorata, Myrsinaceae, Phytochemical screening, Antimicrobial activity, Disc Diffusion Technique, Minimum Inhibitory Concentrations (MIC).
|4||Natural Polymers in the Development of Floating Drug Delivery Systems: A Review |
Kumar Ganesh, Dhyani Archana, Kothiyal Preeti
Abstract: The purpose of writing this review on floating drug delivery systems (FDDS) was to compile the recent literature with special focus on the principal mechanism of floatation to achieve gastric retention . This can be achieved by use of various polymeric substances including natural polymers. These polymers are inexpensive, safe and available in a variety of structures with versatile characteristics. Large number of derivatizable groups, wide range of molecular weights, varying chemical composition gel forming nature of these polymers also provide an exciting opportunities in the fascinating arena of applied polymer science and drug delivery technology. All these characteristics make them suitable candidate for design and fabrication of novel gastroretentive drug delivery systems. Various natural polymers have been investigated worldwide by scientific community for their potential as floating drug delivery systems. The present article highlights various recent efforts and advanced approaches exploiting several natural polymers in this technology.
Keywords: Floating Drug Delivery Systems, Natural Polymers, Site-Specific, Bioavailability.
|5||Nanosuspension: A Novel Drug Delivery System |
Bhatt Ganesh, Raturi Ankita, Kothiyal Preeti
Abstract: Low bioavailability is the major problem associated with poorly soluble drugs. The problem is more complex for drugs which are poorly soluble in both aqueous and nonaqueous media, as solubility is an essential factor for drug absorption, independent of the route of administration. Nanosuspensions have emerged as an attractive and promising approach to improve stability and bioavailability of poorly soluble drugs. These are very finely colloid, biphasic, dispersed, solid drug particles in an aqueous vehicle, size below 1μm, without any matrix material, stabilized by surfactants and polymers. Techniques such as wet milling, high-pressure homogenization, emulsification-solvent evaporation and supercritical fluid have been used in the preparation of nanosuspension. Nanosuspension can be delivered by oral, parenteral, pulmonary and ocular routes.
Keywords: Nanosuspensions, Solubility, Bioavailability, methods of preparation, Homogenization, Drug Delivery