Nanoemulsions are submicron sized emulsions that are under extensive investigation as drug carriers for improving the delivery of therapeutic agents. They are by far the most advanced nanoparticle systems for the systemic delivery of biologically active agents for controlled drug delivery and targeting. Nanoemulsions are the thermodynamically stable isotropic system in which two immiscible liquid (water and oil) are mixed to form a single phase by means of an appropriate surfactants or its mix with a droplet diameter approximately in the range of 0.5-100 um. Nanoemulsion droplet sizes fall typically in the range of 20-200 nm and show narrow size distributions. Nanoemulsion show great promise for the future of cosmetics, diagnostics, drug therapies, and biotechnologies. In this review, the attention is focused to give brief regarding nanoemulsion formulation aspect, method of preparation, characterization techniques with special emphasis on various applications of nanoemulsion in different areas such as in cancer treatment, in drug targeting, as a mucosal vaccine, as a vehicle for transdermal drug delivery and lipophilic drug, as a self-nanoemulsifying and solid self-nanoemulsifying drug delivery system, etc.

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Novel oral drug delivery technologies have emerged and expanded into different drug delivery systems with different drug release mechanisms in the last few decades. Sophisticated instrumentation, modern mathematical models and computational power have revolutionized the entire process of formulation and development of drug delivery systems and advanced the concept of drug delivery from a simple pill to a programmable, time controlled smart system. In situ forming oral controlled release formulation is a new technology in the field of oral controlled release delivery systems. The concept of in situ forming devices (ISFD) entered the pharmaceutical field in the early 1980s as parenteral controlled release dosage forms. In the last decade, this technology has grown significantly due to its potential advantages compared to the traditional parenteral controlled release dosage forms. However, a review of literature revealed that there are not many publications describing the usage of this technology for oral controlled release formulations.

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Promising management of eye ailments take off effective concentration of drug at the eye for sufficient period of time. Ocular drug delivery is hampered by the barriers protecting the eye. The bioavailability of the active drug substance is often the major hurdle to overcome. Conventional ocular dosage form, including eye drops, are no longer sufficient to combat ocular diseases. This article reviews the constraints with conventional ocular therapy, essential factors in ocular pharmacokinetics, and explores various approaches like eye ointments, gel, viscosity enhancers, prodrug, penetration enhancers, microparticles, liposomes, niosomes, ocular inserts, implants, intravitreal injections, nanoparticles, nanosuspension, microemulsion, in situ-forming gel, iontophoresis, and periocular injections to improve the ocular bioavailability of drug and provide continuous and controlled release of the drug to the anterior and posterior chamber of the eye and selected pharmacological future challenges in ophthalmology. In near future, a great deal of attention will be paid to develop noninvasive sustained drug release for both anterior and posterior segment eye disorders. Current momentum in the invention of new drug delivery systems hold a promise toward much improved therapies for the treatment of vision-threatening disorders.

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Floating dosage forms are emerging as a promising novel dosage forms. Floating dosage forms can be prepared as tablets, capsules by incorporating suitable excipients as well by adding certain gas-generating agents, which in turn give the buoyancy to the dosage form in gastrointestinal fluids. The various excipients such as poloxamer 188, carbopol 934P, hydroxypropylmethylcellulose, polyethylene glycol 6000, beta-cyclodextrin, polyvinyl acetate, purified shellac, Eudragit RS, or polymethyl methacrylate, alginate beads and casein-gelatin beads in combination provide buoyancy to the dosage form. The degree of drug embedded in dosage form determines its release. The hydrated layer slowly releases the drug from the dosage form by diffusion. Due to the hydrated gel layer, floating dosage forms can remain afloat in stomach for 6-8 h and release the active pharmaceutical ingredients for extended period of time in gastric environment. These systems have more flexibility in dosage design than conventional dosage form. For the optimization of the drug release pattern in vivo, floating devices such as InteliSite capsule can be used as it provides noninvasive determination of drug absorption and bioavailability at specific sites by gamma scintigraphy. This review summarizes various techniques adopted in the development of floating dosage forms, in vitro and in vivo studies to evaluate the performance and application of floating dosage forms.

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Biopharmaceutics Classification System (BCS) has provided a mechanistic framework for understanding the concept of drug absorption in terms of permeability and solubility. This article reviews the criteria and issues for classifying drugs according to the BCS. Biowaiver extensions for drug or active pharmaceutical ingredient from different BCS classes with scientific basis are discussed as the current BCS guidelines by World Health Organization, Unites State Food and Drug Administration and European Medicines Agency allows for biowaivers based on conservative criteria. The article sheds light on the possible new criteria and class boundaries proposed for additional biowaivers based on the underlying physiology of the gastrointestinal tract in required cases. The potential applications of BCS in drug discovery, drug delivery and drug research as well as extension for BCS are discussed.

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Melatonin, a hormone produced primarily by the pineal gland, is also secreted from the gut and eye during darkness. There are three classes of melatonin receptors, MT ₁ , MT ₂ , and MT ₃ , in various regions of the human brain, gut, ovaries, and blood vessels, but most consistently found in the suprachiasmatic nucleus (SCN) of the hypothalamus and the pars tuberalis of the anterior pituitary. Melatonin has endocrine, autocrine, and paracrine actions, which are mostly receptor mediated. Primary clinical uses include the regulation of circadian rhythms and sleep disorders, although it has other endocrine, immunomodulatory, and oncostatic effects. This review summarizes the current state of melatonin research with an emphasis on its receptors, pharmacological effects, and clinical therapeutic uses.

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Stomach-specific mucoadhesive microspheres as a controlled drug delivery system have been developed to increase gastric retention time of the dosage forms. It is known that differences in gastric physiology, such as gastric pH and motility, exhibit both intra- as well as inter-subject variability demonstrating significant impact on gastric retention time and drug delivery behavior. This article presents the polymers use for mucoadhesive microsphere, factor affecting the mucoadhesion, and preparation techniques of mucoadhesive microsphere. Developments in the techniques for in vitro and in vivo evaluation of mucoadhesive microspheres have also been discussed.

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The floating drug delivery systems (FDDS) become an additional advantage for drugs that are absorbed primarily in the upper segments of gastrointestinal (GI) tract, i.e., the stomach, duodenum and jejunum. Some of the unresolved, critical issues related to the rational development of FDDS include (1) the quantitative efficiency of floating delivery systems in the fasted and fed states; (2) the role of buoyancy in enhancing gastro residence time (GRT) of FDDS; and (3) the correlation between prolonged GRT and sustained release/pharmacokinetic characteristics. Floating drug delivery formulations and the polymers used in these systems have become much more sophisticated, with the ability to do more than simply extend the effective release period for a particular drug. While much of work is still in its early stages, to develop newer polymers and optimization of different polymer combination for development of FDDSs. From review of literature related on FDD it is suggested that future research work in the FDDSs should be aimed at discovering means to accurately control the drug input rate into the GI tract for the optimization of the pharmacokinetic and toxicological profiles of medicinal agents by selecting proper polymers.

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The process of drug discovery is very complex and requires an interdisciplinary effort to design effective and commercially feasible drugs. The objective of drug design is to find a chemical compound that can fit to a specific cavity on a protein target both geometrically and chemically. After passing the animal tests and human clinical trials, this compound becomes a drug available to patients. The conventional drug design methods include random screening of chemicals found in nature or synthesized in laboratories. The problems with this method are long design cycle and high cost. Modern approach including structure-based drug design with the help of informatic technologies and computational methods has speeded up the drug discovery process in an efficient manner. Remarkable progress has been made during the past five years in almost all the areas concerned with drug design and discovery. An improved generation of softwares with easy operation and superior computational tools to generate chemically stable and worthy compounds with refinement capability has been developed. These tools can tap into cheminformation to shorten the cycle of drug discovery, and thus make drug discovery more cost-effective. A complete overview of drug discovery process with comparison of conventional approaches of drug discovery is discussed here. Special emphasis is given on computational approaches for drug discovery along with salient features and applications of the softwares used in de novo drug designing.

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Delivery systems with a pulsatile release pattern are receiving a sprouting attraction for the development of drugs for which conventional controlled-release systems with a continuous release are not ideal. Most physiological, biochemical, and molecular processes in healthy organisms display robust, predictable changes on a 24-h schedule. Chronotherapeutic products can synchronize drug delivery with circadian rhythms in order to optimize efficacy and/or minimize side effects. These products follow a sigmoidal release profile characterized by a time period of no release (lag time) followed by a rapid and complete drug release. Various capsular, osmotic, single and multiple unit systems are based on the use of soluble/erodible polymer coatings, rupturable membranes, and membrane permeabilities. Marketed technologies such as PULSYS™, CODAS^® , TIMERx^® , and DIFFUCAPS^® follow one of the above mechanisms to render a sigmoidal drug release profile. So these systems are tuned according to body's circadian clock having a potential to improve quality of patients life undergoing conventional drug therapy.

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This review work gives a lot of information on polyelectrolyte complexes (PECs). The complex formed is generally applied in different dosage forms for the formulation of stable aggregated macromolecules. Many properties like diffusion coefficient, chain conformation, viscosity, polarizability, miscibility, etc., are drastically changed due to the introduction of a polyelectrolyte. The formation of PECs is influenced not only by chemical properties like stereochemical fitting, their molecular weight, charge densities, etc. but also by secondary experimental conditions like concentration of polyelectrolytes prior to mixing, their mixing ratio, ionic strength of the solution, mixing order, etc. The formation of PECs is described in this article and it is divided into three main classes, i.e., primary complex formation, formation process within intracomplexes and intercomplex aggregation process. There are different types of PECs obtained according to binding agents such as polymers, proteins, surfactants, drugs, etc. Other factors which affect the formation of PECs are also discussed. There are a number of pharmaceutical applications of polyelectrolytes, such as in controlled release systems, for the enzyme and cell support, for different types of tissue reconstitution, etc.

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Pharmaceutical invention and research are increasingly focusing on delivery systems which enhance desirable therapeutic objectives while minimizing side effects. Recent trends indicate that drug delivery systems are especially suitable for achieving controlled or delayed release oral formulations with low risk of dose dumping, flexibility of blending to attain desirable release patterns with less inter- and intra-subject variability. A blend of floating and pulsatile principles of drug delivery system seems to present the advantage that a drug can be released in the upper GI tract after a definite time period of no drug release. Floating pulsatile drug delivery system (FPDDS) concept was applied to increase the gastric residence of the dosage form having lag phase followed by a burst release. Diseases wherein FPDDS are promising include asthma, peptic ulcer, cardiovascular diseases, arthritis, and attention deficit syndrome in children. To overcome limitations of various approaches for imparting, buoyancy and lag controlling were prepared by floating pulsatile delivery systems, for which time-controlling system like swelling and rupturable membranes, soluble or erodible coating, capsule-shaped system, and multiparticulate system are primarily involved in the control of release. FPDDS showed excellent lag phase followed by burst release in distal part of small intestine which gives site- and time-specific release of drugs acting as per chronotherapy of the diseases. The current article focuses on the diseases requiring FPDDS, methodologies involved for the existing systems, recent update.

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Polymers are complex carbohydrates having good mechanical properties for application as fiber, films, adhesives, rheology modifiers, hydrogels, emulsifiers, and drug delivery agents. Tamarind seed polysaccharide (TSP) is a glucosaminoglycan derivative extracted from the kernel of seeds of Tamarindus indica Linn., Family Leguminosae. A polymer consists of cellulose-type spine that carries xylose and galactoxylose substituents. It can be used as a binder in tablets, as a mucoadhesive for buccal or sublingual delivery of drugs, in gastro-intestinal targeting as a bioadhesive tablet, and for ocular delivery of drugs for achieving zero-order controlled release. They also act as a carrier for delivery of certain drugs. TSP future perspective is wide application as a promising polymer in pharmaceutical industry as a novel carrier of drugs in various bioadhesive and other sustained release formulations.

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Colon-specific drug delivery has gained increased importance for the delivery of drugs for the treatment of local diseases associated with the colon. To deliver the compounds in a non-degraded form to the lower part of the gastrointestinal tract, they must first of all pass through the stomach, the upper part of the intestine and must use the characteristics of the colon to specifically release the drugs in this part of the digestive tract. The use of biodegradable polymers holds great promise to achieve targeted drug release to the colon. The family of natural polymers has great appeal to drug delivery as it comprises polymers with a large number of derivatizable groups, a wide range of molecular weights, varying chemical compositions, low toxicity, and biodegradability yet high stability. Polysaccharidases are bacterial enzymes that are available in sufficient quantity to degrade these natural polysaccharides. This article also discusses few delivery systems designed to target a drug to the colon.

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A nondestructive evaluation of tablets is possible with the application of near-infrared spectroscopy and appropriate statistical techniques. Tablet hardness, disintegration time, dissolution, drug and excipient content, particle size, identification of actives and/or excipients, etc. are possible with the help of near-infrared spectroscopy. The established methods using this technique are rapid and simple. The technique also has found its place in quality assurance and quality control of tablets. It has been suggested as a useful method for the real time in-process testing and is a valuable process analytical technology tool.

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Since the Nobel prize-winning discovery of RNA interference (RNAi) in 1998, considerable money has been invested in the investigation of therapeutic potential of RNA interference (RNAi) and its application in human diseases. Encouraging results of ongoing clinical trials for the treatment of age-related macular degeneration and respiratory syncytial virus have further propelled the investment, research, and hope for a promising outcome. Due to the astonishing efforts in this field, more than 13 siRNA-based formulations are now being evaluated in clinical trials, more than 80 patents have been granted, and more than 500 patent applications have been published in 2009 in the United States alone. Despite this brisk growth, the application of RNAi therapeutics requires the development of safe, effective, and clinically suitable delivery carriers. This review highlights the evolution of siRNA technology, need of siRNA in therapeutics with specific focus on delivery challenges and clinical status, and an overview of its patent thrust.

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Controlled drug through diffusion and activation-based drug delivery devices have become commercially feasible due to converging technologies and regulatory accommodation. Combination products constructed using implantable technology offer revolutionary opportunities to address unmet medical needs related to dosing. These products have the potential to completely con trol drug release, meeting requirements for on-demand pulsatile or adjustable continuous administration for extended periods. Implantable technologies, materials science, data management, and biological science have significantly developed in recent years, providing a multidisciplinary foundation for developing integrated therapeutic systems. If small-scale biosensor and drug reservoir units are combined and implanted, a wireless integrated system can regulate drug release, receive sensor feedback, and transmit updates. The tools such as microfabrication technology, information science, and systems biology are being combined to design increasingly sophisticated drug delivery systems that promise to significantly improve medical care.

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Self-emulsifying drug delivery systems (SEDDSs) have gained exposure for their ability to increase solubility and bioavailability of poorly soluble drugs. SEDDSs are mixtures of oils, surfactants, and cosurfactants, which are emulsified in aqueous media under conditions of gentle stirring and digestive motility that are encountered in the gastrointestinal (GI) tract. We found that SEDDSs could efficiently improve oral absorption of the sparingly soluble drugs by rapid self-emulsification and, subsequently, dispersion in the absorption sites. SEDDSs possess unparalleled potential in improving oral bioavailability of poorly water soluble drugs. Following their oral administration, these systems rapidly disperse in GI fluids, yielding micro-or nanoemulsions containing the solubilized drug. Owing to its miniscule globule size, the micro/nanoemulsifed drug can easily be absorbed through lymphatic pathways, bypassing the hepatic first-pass effect.

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Particle size enlargement is the process of transforming fine particles into larger particles by the introduction of external forces, and is a value-added step in many processes involving powdered materials. There are many different reasons to enlarge particle size, including increased flowability and improved product shape and appearance. With the multitude of options available to achieve enlarged particle product, it can be difficult to narrow down the best method for the desired application. The main factor in selecting the right kind of method is to specify the type of end product required. In the pharmaceutical industry in particular, uniform flow of solid mixtures is one of the most important considerations in solid dosage manufacture. The particle size distribution, shape, hardness, and moisture content of the powder particles govern its flow and compactibility property. This article outlines making of enlarged particles and understanding their behavior.

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Ascorbic acid (vitamin C) and its derivatives are known to perform various important physiological and metabolic functions in humans. In addition to dietary supplements, a number of topical formulations containing ascorbic acid and derivatives are now available that induce collagen synthesis, strengthening of skin tissues, reduction in pigmentation loss, and improved growth and health activities. It has also been used in a variety of cosmetic preparations as an antioxidant, pH adjuster, anti-aging and photoprotecting agent. Ascorbic acid is highly sensitive to air and light; and to achieve its stabilization in cosmetic preparations, it has been suggested to use ascorbic acid in microencapsulation form, in combination with other chemical moieties such as vitamin-E, by the control of pH and electrolyte concentration and use of stabilizing agents like citric, tartaric, or ferulic acids. A large number of cosmetic creams and lotions are available in the market containing the derivatives of ascorbic acid (e.g., sodium ascorbate, ascorbyl palmitate). Although these preparations are chemically stable, they lack the pharmacological activity of ascorbic acid. In the present review, it has been emphasized to consider the importance of various factors involved in the formulation of such preparations to achieve the stabilization of ascorbic acid as such, to maintain its pharmacological activity.

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Breast cancer is the most common cause of cancer-related death among women worldwide, with case fatality rates highest in low-resource countries. Despite significant scientific advances in its management, most of the world faces resource constraints that limit the capacity to improve early detection, diagnosis, and treatment of the disease. There are different types of breast cancer, and different treatments that can work for each. Breast cancer is a highly complex disease with many treatment options including surgery, radiotherapy, hormonal therapy, biological therapy and chemotherapy. Optimizing standard treatment modalities for breast cancer has improved the outlook for women afflicted with it, but the fact that 40% still ultimately die from the disease highlights the need for new therapies. Remarkable advances in molecular immunology and biotechnology have created a unique opportunity for developing active vaccination strategies that engage the patient's own immune system in the fight against breast cancer. This article will review current drugs used in treatment of breast cancer and the novel targets which will be used safe and effective management of breast cancer.

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The purpose of writing this review to compile the current technological development of floating drug delivery system (FDDS), advantages and future potential for oral controlled drug delivery. The review includes various approaches which are currently utilized in the prolongation of the gastric residence time (GRT) and their classification. This review also summarizes various in vitro and in vivo techniques to evaluate the performance and application of these systems.

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Renin-angiotensin-aldosterone systems play a major role in the regulation of human homeostasis mechanism, which are also involved in the development of hypertension and end-organ damage through activation of angiotensin II. Inhibitors of the renin-angiotensin-aldosterone system may reduce the development of end-organ damage to a greater extent than other antihypertensive agents. Aliskiren is the first member of the new class of orally active direct renin inhibitors recently approved by the US Food and Drug Administration for the treatment of hypertension. Aliskiren directly inhibiting the renin and reducing the formation of angiotensin II, which is the most effective mediator involved in the pathogenesis of cardiovascular diseases. The present review mainly focuses on the pharmacodynamics and pharmacokinetics and clinical aspects of aliskiren. In this respect, the review will improve the basic idea to understand the pharmacology of aliskiren, which is useful for the further research in cardiovascular disease.

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Porphyran, sulfated polysaccharide, is derived from the cell wall and intercellular regions of Porphyra and known to be closely related to agarose in its basic structure, whereas it is very different in terms of having L-galactose-6-sulfate. Besides of various physiological effects, it is having wide pharmaceutical applications. Its structure-related gelling and emulsification properties have given birth to a new polymer in polymeric science. Porphyran uses are based on their unique properties to form strong gels after desulfation in an aqueous solution. This gel results from peculiar regular chemical structures, specific ordered molecular conformations, and aggregations. Now a days, new methodologies and instruments have provided a more accurate view of the relationships between the chemical structure and the gelling characteristics of these complex hybrid and heterogeneous polysaccharides. NMR is the single most powerful technique for solving the structures of intact polysaccharides. Developments in the NMR render the determination of structural distribution of this galactan more accessible. Such techniques also yield new information on the aggregate formation of these sulfated polysaccharides. These and other data question the existence of the generally assumed intertwined double helical conformations of these galactans during gel formation. Currently, porphyran availability is not known because of several problems such as its high molecular weight and viscosity that are suppressing its growth in world market. Hence, world market needs development of this novel compound to improve its pharmaceutical applications though this is an area of algal utilization that demands more research.

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While major advancements in the discipline of pharmacovigilance have taken place in the West, not much has been achieved in India. However, with more clinical trials and clinical research activity being conducted in India, there is an immense need to understand and implement pharmacovigilance. Pharmacovigilance is the pharmacological science relating to the detection, assessment, understanding and prevention of adverse effects, particularly long-term and short-term adverse effects of medicines. As a means of pooling existing data on adverse drug reactions (ADRs), the World Health Organization (WHO) Programme for International Drug Monitoring was started in 1968. Currently, 86 countries participate in the programme, which is coordinated by WHO together with its collaborating centre in Uppsala, Sweden. The origin of pharmacovigilance in India goes back to 1986, when a formal ADR monitoring system consisting of 12 regional centers, each covering a population of 50 million, was proposed for India. The National Pharmacovigilance Program established in January 2005, was to be overseen by the National Pharmacovigilance Advisory Committee based in the Central Drugs Standard Control Organization (CDSCO), New Delhi. This article gives a systematic review of the pharmacovigilance in India from its origin to the current scenario and also discusses the various strategies and proposals to build, maintain and implement a robust pharmacovigilance system for India in the coming years.

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