ABSTRACT

The objective of the present research work was to develop floating microcarries of Stavudine, to prolong the gastric residence time, bioavailability, to minimize the dose depend side effects and improves patient compliance. Emulsion gelation technique was used to prepare the floating microcarriers using sodium alginate as the polymer. Microcarriers containing oil was prepared by gently mixing and homogenizing oil and water phase containing sodium alginate which was then extruded into calcium chloride solution. The prepared microcarriers were evaluated for drug entrapment efficiency, particle size and shape, micrometric properties, buoyancy and invitro drug release studies. The results of FTIR spectroscopy showed stable character of Stavudine. The mean particle size of microcarriers was in the range of 0.59-1.25mm. Microcarriers were spherical and free flowing. The drug entrapment efficiency was found to be 44.6-69.1%. The microcarriers remained buoyant for more than about 12h. The drug release study showed that Stavudine from the microcarriers was prolonged more than 10hrs. The results demonstrate that the amount of the oil entrapped in each microcarrier is play role in particle size entrapment efficiency and in vitro drug release.

Key words: Microcarriers, Emulsion gelation, Sodium alginate, Stavudine.

ABSTRACT

A validated derivatization spectrofluorometric method was developed for the determination of artesunate and artemether in tablet dosage form. Artesunate and artemether are semi synthetic drugs obtained as a derivative of artemisinin. Both of the drugs did not have native fluorescence with a fused sesquiterpene lactone ring system varying in the substitution at C10.The drug artemether was treated with acetic anhydride and sulphuric acid and artesunate was treated with acetic acid and sulphuric acid in fixed ratio and heated to convert the compounds into a fluorescent moiety. The peroxide linkage present in the fused lactone ring system is converted into a unsaturated group for artemether and artesunate. The excitation wavelength was found to be at 438 nm and 303 nm whereas the emission wavelength was found at 508 nm and 609 nm for artesunate and artemether respectively. The method was validated according to the ICH guidelines for validation of analytical procedures. The linearity was found in the concentration range of 100 to 500 ng/ml for artesunate and between 100 to 800 ng/ml for artemether. The assay values were found between 98.2 to 100.67 % for both the compounds with a %RSD of 0.022842 and 0.4740 respectively. The % RSD of intraday and interday assay was found to be less than 1. Hence the reported method was found to be precise and accurate for the quantitative determination of artesunate and artemether in tablet dosage form. The interference studies was done with the excipients present in the formulations and found to have no interferences. The solution of artesunate was found to be stable for 2 hours and for artemether was found to be stable for 1 hour.

Key words: Spectrofluorimetry, Artemether, Artesunate, Derivatization, Validation.

ABSTRACT

Delivering the drug accurately and safely to its target site at the precise time period to have a controlled release and attain the maximum therapeutic effect remains a benchmark in the design and development of newer drug delivery systems. In this review, the latest research developments of the Solid lipid nanoparticles (SLNs) according to the recent relevant literatures were focused. This paper highlights various production techniques for SLNs as well as their advantages and disadvantages. Analytical techniques for characterization of SLNs like electron microscopy, dynamic light scattering, atomic force microscopy, differential scanning calorimetry, X-ray diffraction, nuclear magnetic resonance and electron spin resonance were discussed. Aspects of principles of drug release and different administration routes of SLNs were described. These SLNs have been claimed to overcome the shortcomings of other colloidal drug delivery systems.

Key words: Solid lipid nanoparticles, Colloidal carriers, Production techniques, Advantages, Disadvantages, Administration routes.

ABSTRACT

Considerable attention has been focused in recent years on the delivery of drugs through the oral mucosa which have a high first pass metabolism or degrade in the gastrointestinal tract. Buccal delivery involves the administration of the desired drug through the buccal mucosal membrane lining of the oral cavity. Unlike oral drug delivery, which presents a hostile environment for drugs, especially proteins and polypeptides, due to acid hydrolysis and the hepatic first-pass effect, the mucosal lining of buccal tissues provides a much milder environment for drug absorption. The effective physiological removal mechanisms of the oral cavity that take the formulation away from the absorption site are the other obstacles that have to be considered. The strategies studied to overcome such obstacles include the employment of new materials that, possibly, combine mucoadhesive, enzyme inhibitory and penetration enhancer properties and the design of innovative drug delivery systems which, besides improving patient compliance, favor a more intimate contact of the drug with the absorption mucosa. This presents a brief description of advantages and limitations of buccal drug delivery and the anatomical structure of oral mucosa, mechanisms of drug permeation followed by current formulation design in line with developments in buccal delivery systems and methodology in evaluating buccal formulations.

Key words: Mucoadhesive Drug Delivery System, Suitable delivery devices, Permeation enhancers, Saliva.

ABSTRACT

As drug delivery systems Nanoparticulate widely investigated because of many advantages such as smaller size, controlled drug release potential, targeting ability, enhancement of therapeutic efficacy and reduction of toxicity. So, Solid Lipid Nanoparticles(SLNs) have recently received considerable attention as alternative drug delivery carrier. The aim of present work was to formulate Moxifloxacin loaded solid lipid nanoparticles (SLNS) using palmitic acid as a lipophilic material, Tween 80 and poloxamer as surfactants and methanol, butanol as cosolvents. The SLNs were prepared by o/w microemulsion technique which involves high speed homogenization. Moxifloxacin loaded SLNs seem to have dimensional properties useful for topical administration. The SLNs were characterized for particle size analysis, zeta potential, drug content, entrapment efficiency, Scanning Electron Microscopy (SEM) photographs, Differential scanning calorimetry (DSC) and IR studies. Results indicated mixed lipid-matrix produced nanosuspensions with low-crystallinity, smaller particle sizes, no drug-excipient incompatibility and higher drug entrapment. The optimized formulation was incorporated into various gels like carbopol and xanthan gum gel. Preliminary physical parameters of gels like viscosity, gel strength were evaluated. In vitro drug release studies were carried out for moxifloxacin SLN loaded gel preparations and % drug loading capacity was calculated. Ex vivo penetration studies were conducted for 12 hrs using Keshary Chien diffusion cell. The studies revealed a stable formulation without precipitation of drug and a sustained drug release from the gel matrix. SLN composed of moxifloxacin would prove to be a good topical drug delivery in treating bacterial infections.

Key words: Moxifloxacin, poloxamer, carbopol, xanthan gum, nanosuspensions, zeta potential.

ABSTRACT

Direct compression of powders is simplest and easiest way of making tablets. Good flowability and compressibility plays a major role for direct compression of drugs. There are several techniques available to impart desired compressibility to drugs. Spherical crystallization techniques are reliable techniques in which the drug crystals are modified using different solvents to directly compressible spherical agglomerates, which less economical and time saving. The use of spherical crystallization as a technique appears to be efficient alternative for obtaining suitable particles for direct compression. Spherical crystallization is a particle design technique, by which crystallization, agglomeration and spheronization can be carried out simultaneously in one step.

Key words: Direct compression, Spherical crystallization, Spherical agglomerates crystallization, Agglomeration, Spheronization.