Kumar Bishwajit Sutradhar

Increasing Possibilities of Nanosuspension

Nowadays, a very large proportion of new drug candidates emerging from drug discovery programmes are water insoluble and thus poorly bioavailable. To avoid this problem, nanotechnology for drug delivery has gained much interest as a way to improve the solubility problems. Nano refers to particles size range of 1–1000 nm. The reduction of drug particles into the submicron range leads to a significant increase in the dissolution rate and therefore enhances bioavailability. Nanosuspensions are part of nanotechnology. This interacts with the body at subcellular (i.e., molecular) scales with a high degree of specificity and can be potentially translated into targeted cellular and tissue-specific clinical applications designed to achieve maximal therapeutic efficacy with minimal side effects. Production of drugs as nanosuspensions can be developed for drug delivery systems as an oral formulation and nonoral administration. Here, this review describes the methods of pharmaceutical nanosuspension production including advantages and disadvantages, potential benefits, characterization tests, and pharmaceutical applications in drug delivery.

Implantable microchip: the futuristic controlled drug delivery system

Abstract There is no doubt that controlled and pulsatile drug delivery system is an important challenge in medicine over the conventional drug delivery system in case of therapeutic efficacy. However, the conventional drug delivery systems often offer a limited by their inability to drug delivery which consists of systemic toxicity, narrow therapeutic window, complex dosing schedule for long term treatment etc. Therefore, there has been a search for the drug delivery system that exhibit broad enhancing activity for more drugs with less complication. More recently, some elegant study has noted that, a new type of micro-electrochemical system or MEMS-based drug delivery systems called microchip has been improved to overcome the problems related to conventional drug delivery. Moreover, micro-fabrication technology has enabled to develop the implantable controlled released microchip devices with improved drug administration and patient compliance. In this article, we have presented an overview of the investigations on the feasibility and application of microchip as an advanced drug delivery system. Commercial manufacturing materials and methods, related other research works and current advancement of the microchips for controlled drug delivery have also been summarized.

Irrational U se of Antibiotics and Antibiotic Resistance in Southern Rural Bangladesh: Perspectives from Both thePhysicians and Patients

Aims: Antibiotic resistance is one of the widely recognized public health challenges in Bangladesh. The present study was aimed to analyze the current status of irrational use of antibiotics in rural Bangladesh and to explore the views from both physicians’ and patients’ perspective. Study Design: Population based survey. Place and Duration of Study: The survey was conducted among 6,000 patients and 580 physicians in the rural areas of Dhaka and Rajshahi divisions of Bangladesh from July 2012 to December 2012. Methodology: The survey followed a face-to-face interview protocol. 24 Upazila Health Complexes and 112 Union Health Centers of Dhaka and Rajshahi divisions were conveniently surveyed by trained volunteer interviewers. Two separate survey questionnaires were developed for physician and patient survey. Results: From the physician survey it was found that significantly more doctors prescribe antibiotics in suspected infections (P<.0001). Around forty-four (44.1) percent doctors prescribe antibiotics in cold and fever before diagnosis. A significant proportion of physicians never receive any feedback about the antibiotic they prescribe (31.9%, P<.0001) and more than 50% doctors claimed that they receive feedback occasionally, not always (P<.0001). According to the physician’s patient non-compliance is the main cause of antibiotic resistance in the country (68.8%). Though 48.6% patients think that it is important to strictly follow the doctor’s prescription, a significant percentage believe that it is not always necessary (26.7%, P<.0001) and more than 50% patient stop taking the antibiotic as soon as the symptoms disappear, while only 25.2% patient complete their full course. Only 6.3% patients consult their doctor if they miss the dose of an antibiotic and more than 50% take the next dose on time (P<.0001). When a drug does not work the patient usually consider the doctor is incompetent (25.6%) and many (24.5%) believe that the quality of the drug is not up to the mark. Conclusion: The result of this survey indicates that the antibiotics are used among the rural people in irrational way. To overcome this situation close supervision of the relevant authority is required in order to minimize the growing antibiotic resistance in Bangladesh.

Water hyacinth: a possible alternative rate retarding natural polymer used in sustained release tablet design

In recent years natural polymers have been widely used because of their effectiveness and availability over synthetic polymers. In this present investigation matrix tablets of Metformin hydrochloride were formulated using Water hyacinth powder and its rate retardant activity was studied. Tablets were prepared using wet granulation method with 8% starch as granulating agent and 5, 10, 15, 20, 25 and 30% of Water hyacinth powder to the drug. In preformulation study, angle of repose, Carrs Index and Hausner ratio were calculated. Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM) studies were performed and no interactions were found between drug and excipients. Weight variation, friability, hardness, thickness, diameter, and in vitro release study were performed with the prepared matrix tablets. Dissolution studies were conducted using USP type II apparatus at a speed of 100 rpm at 37°C ± 0.5 temperature for 8 h. Though all the formulations comply with both BP and USP requirements, formulation F-1 (5% of Water hyacinth) was the best fitted formula. The drug release patterns were explained in different kinetic models such as Zero order, First order, Higuchi, Hixson Crowell, and Korsmeyer-Peppas equations. The current investigation implies that Water hyacinth has the potential to be used as a rate-retarding agent in sustained release drug formulations.