A review of literature was carried out to determine methods of production of liposomes, their stability, biodistribution and their uses as drug delivery systems. The conventional method of preparing liposomes is basically for the multilamellar vesicles (MLVs). However, other methods are used to reduce the size of these MLVs to small unilamellar vesicles (SUVs) so as to increase their plasma lifetime and consequently increase the possibility of achieving greater tissue localisation. Some of these methods of size reduction are sonication and high pressure extrusion. Each of these methods has its own advantages and disadvantages. Large unilamellar vesicles (LUVs), on the other hand, are prepared mainly by detergent removal method and reverse phase extrusion technique. There are also improved pharmacokinetic properties with liposomal drugs compared to free drugs, though some formulation factors affect the release kinetics of the liposomal drugs. The review also shows that liposomes have a lot of biomedical applications and uses. They have been used in drug targeting, oral delivery of vaccines, insulins, peptides and some compounds, which are usually degraded in the gastrointestinal tract. It has also found application in topical therapy especially in the eye and lungs. Other areas of application are in cancer chemotherapy and treatment of human immunovirus (HIV) infection. The control of the stability of liposomes is an essential prerequisite for effective use as drug carriers. Leakage of the liposome is attributable mainly to differences in lamellar structure. For instance, MLVs are less prone to leakage than ULVs. The use of a combination of saturated phospholipid and cholesterol in the formulation of the liposomes has also been found to enhance stability with lower tendency to leakage.

Ion exchange resins (IER) are insoluble polymers that contain acidic or basic functional groups and have the ability to exchange counter-ions within aqueous solutions surrounding them. Based on the nature of the exchangeable ion of the resin as a cation or anion, it is classified as cationic or anionic exchange resins, respectively. The efficacy of ion exchange resins mainly depends upon their physical properties such as degree of cross-linking, porosity, acid base strength, stability, purity and particle size. Modified release of drugs from resinate (drug-resin complexes) is another potential application of ion exchange resins.  Due to the versatile utility of ion exchange resins, they are being used for various drug delivery and therapeutic applications. Resins used are polymers that contain appropriately substituted acidic groups, such as carboxylic and sulfonic for cation exchangers; or basic groups, such as quaternary ammonium group for anion exchangers. This review addresses different types of ion exchange resin, their properties, the chemistry; role of IER in controlled drug delivery systems, its therapeutic applications, methods of preparation of IER along with their resonates. Keywords: Anion exchange; Cation exchange; Resin; Controlled release; Resinates; Drug delivery. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v2i3.4991               J. Sci. Res. 2 (3), 599-613 (2010)

Gastric retentive floating drug delivery system (GFDDS) is enabled the prolonged continuous input of the drug to the upper parts of the gastrointestinal (GI) tract and improves the bioavailability of medications with narrow absorption window. The design of the delivery system is based on the controlled release formulation with floating and swelling features in order to prolong the gastric retention time of the drug delivery systems. In the present study norfloxacin as candidate, guar gum, sodium CMC, HPMC15 KM is studied along with other excipients like PVP K30 (binder), sodium bicarbonate microcrystalline cellulose were used in different concentrations to get the desired controlled release profile over a period of 12 hrs. All the formulations were evaluated for buoyancy lag time, duration of buoyancy, dimensional stability, drug content and in vitro drug release profile. Based on the in vitro studies carried out for the optimized formulation by dissolution the performance of the developed formulation promises to be efficient in controlling the drug release rate with the guar gum, a natural polymer.DOI: http://dx.doi.org/10.3329/icpj.v1i7.10809International Current Pharmaceutical Journal 2012, 1(7): 155-164

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The purpose of writing this review on pulsatile drug delivery systems (PDDS) is to compile the recent literatures with special focus on the different types and approaches involved in the development of the formulation. PDDS are gaining importance in the field of pharmaceutical technology as these systems deliver the right dose at specific time at a specific site. Some of the disease conditions wherein PDDS are promising include duodenal ulcer, cardiovascular diseases, arthritis, asthma, diabetes, neurological disorder, cancer, hypertension and hypercholesterolemia. PDDS can be classified into time controlled systems wherein the drug release is controlled primarily by the delivery system, stimuli induced PDDS in which release is controlled by the stimuli, such as the pH or enzymes present in the intestinal tract or enzymes present in the drug delivery system and externally regulated system where release is programmed by external stimuli like magnetism, ultrasound, electrical effect and irradiation. This review also summarizes some current PDDS already available in the market. These systems are useful to several problems encountered during the development of a pharmaceutical dosage form.

an online international journal allowing free unlimited access to abstract and full-text of published articles. The journal is devoted to the promotion of health sciences and related disciplines (including medicine, pharmacy, nursing, biotechnology, cell and molecular biology, and related engineering fields). It seeks particularly (but not exclusively) to encourage multidisciplinary research and collaboration among scientists, the industry and the healthcare professionals. It will also provide an international forum for the communication and evaluation of data, methods and findings in health sciences and related disciplines. The journal welcomes original research papers, reviews and case reports on current topics of special interest and relevance. All manuscripts will be subject to rapid peer review. Those of high quality (not previously published and not under consideration for publication) will be published without delay. The maximum length of manuscripts should normally be 10,000 words (20 single-spaced typewritten pages) for review, 6,000 words for research articles, 3,000 for technical notes, case reports, commentaries and short communications. Submission of Manuscript:The International Journal of Health Research uses a journal management software to allow authors track the changes to their submission. All manuscripts must be in MS Word and in English and should be submitted online at http://www.ijhr.org. Authors who do not want to submit online or cannot submit online should send their manuscript by e-mail attachment (in single file) to the editorial office below. Submission of a manuscript is an indication that the content has not been published or under consideration for publication elsewhere. Authors may submit the names of expert reviewers or those they do not want to review their papers. Enquirie Review Article Chronobiology and Chronotherapy of Hypertension -A Review AbstractHypertension occurs in over 90% of all patients with cardiovascular disease (CVD) in the United States and it is a major risk factor for end-organ damage, CVD and death. In the treatment of hypertension, investigation of chronobiology, chronopharmacology and chronotherapy began a few decades ago. Studies over the last decade have revealed that blood pressure (BP) and CVD are influenced by our behaviour such as what we eat and even conditioned by the time of day. Also, the ability of the night: day ratio of systolic BP predicts the risk for cardiovascular events more accurately compared with office BP measured only at once. Evidence clearly points to the fact that nocturnal BP is indeed the BP as it is most consistently correlated with prediction of cardiovascular risk and provides more close surveillance of safety. Circadian rhythm is a significant input into the regulation of BP. Hence, a circadian disorder such as hypertension requires chronopharmacotherapy. However, different medications have been studied for their chronopharmacology and potential chronotherapy. This article reviews the chronobiology of hypertension, and the ...

The aim of this study was to evaluate the suspending properties of Brachystegia eurycoma gum on metronidazole suspension. The suspending properties of Brachystegia eurycoma gum (family leguminosae) were evaluated comparatively with that of compound tragacanth powder at concentration range of 2.5 – 10.0%w/v in metronidazole suspension. The following parameters were determined; sedimentation volume (%), viscosity, pH and re-dispersion number. The values obtained were used as basis for comparison of the suspending agents studied. Brachystegia eurycoma and compound tragacanth gums had a pH range between 4.7 to 4.9 and between 3.9 to 4.1 respectively which indicates that they are slightly acidic. Particles suspended with tragacanth gum at concentration ? 7.5%w/w redispersed easily than those formulated with the Brachystegia eurycoma gum at ? 10% w/w. It was observed that with increase in concentration of the gum the viscosity of the suspension increased correspondingly. For instance, at concentration of 2.5%w/w viscosities of the suspensions are 490 poise (Brachystegia eurycoma gum) and 603 poise (compound tragacanth gum) while at concentrations of 7.5%w/w their viscosities were 914 poise (Brachystegia eurycoma gum) and 1709 poise (compound tragacanth gum). There was a direct proportionality between viscosity of the gums at different concentrations and the sedimentation rate of the suspensions, as the viscosity of the gum increases, the rate of sedimentation of the suspension decreases. Brachystegia eurycoma gum at predetermined concentration can be exploited as an alternative excipient in the formulation of pharmaceutical suspensions of insoluble substances.DOI: http://dx.doi.org/10.3329/icpj.v3i11.20727 International Current Pharmaceutical Journal, October 2014, 3(11): 328-330