Hamid A Merchant

Learn More
Laboratory animals are often used in drug delivery and research. However, basic information about their gastrointestinal pH, fluid volume, and lymphoid tissue is not completely known. We have investigated these post-mortem in healthy guinea pigs, rabbits and pigs, to assess their suitability for pre-clinical studies by comparing the results with reported(More)
The aim of this study is to develop a once-daily sustained release matrix tablet of ibuprofen using hydroxypropyl methylcellulose (HPMC) as release controlling factor and to evaluate drug release parameters as per various release kinetic models. In order to achieve required sustained release profile tablets were directly compressed using Avicel pH 101 and(More)
The use of compendial pH 6.8 phosphate buffer to assess dissolution of enteric coated products gives rise to poor in vitro-in vivo correlations because of the inadequacy of the buffer to resemble small intestinal fluids. A more representative and physiological medium, pH 6.8 bicarbonate buffer, was developed to evaluate the dissolution behaviour of enteric(More)
Oral modified-release dosage forms can be designed with the aim of achieving specific pharmacokinetic profiles, delivering to specific gut localities or reducing the number of drug administrations. Multiple-unit systems, such as pellets, beads or granules, often claim superiority to single-unit modified-release formulations in terms of predictability and(More)
Bicarbonate media are reflective of the ionic composition and buffer capacity of small intestinal luminal fluids. Here we investigate methods to stabilise bicarbonate buffers which can be readily applied to USP-II dissolution apparatus. The in vitro drug release behaviour of three enteric coated mesalazine (mesalamine) products is investigated. Asacol 400(More)
Despite rapid dissolution in compendial phosphate buffers, gastro resistant (enteric coated) products can take up to 2 h to disintegrate in the human small intestine, which clearly highlights the inadequacy of the in vitro test method to predict in vivo behaviour of these formulations. The aim of this study was to establish the utility of a novel pH 5.6(More)
Decreasing the dose frequency of cefpodoxime proxetil increases patient compliance; patients prefer to take the drug once daily. It also improves the rate of bacterial killing and hastens the cure from the indications, and therefore increases compliance. The hydrophilic matrix of HPMC controlled the cefpodoxime proxetil release effectively for 24 hours;(More)
We all respond differently to drugs. Personalised medicine aims to improve efficacy and reduce side effects, and efforts are being made to understand the physiological differences that underlie responses to drugs. Genetics, diet and disease state can be key; however, gender also plays an important role in pharmacokinetics, pharmacodynamics and drug(More)
Physiological functions of the two extreme ends of the age spectrum, children (<18 y old) and older adults (aged 65 y and over), differ from healthy young adults. This consequently affects the pharmacokinetic profiles of administered drugs, which, in turn, impacts upon clinical practice and drug therapy. The gastrointestinal milieu acts as a distinct and(More)
The aminosalicylate mesalazine (mesalamine) forms the mainstay of treatment in ulcerative colitis (UC), a disease for which many commercial modified-release products have been developed with the aim of providing targeted gastrointestinal release. The release profiles of five of these commercial formulations were evaluated in bicarbonate buffer using a novel(More)