Glucosamine HCl-based solid dispersions to enhance the biopharmaceutical properties of acyclovir

The objective of the work presented here was to assess the feasibility of using glucosamine HCl as a solid-dispersion (SD) carrier to enhance the biopharmaceutical properties of a BCS class III/IV drug, acyclovir (ACV). The solid-dispersions of acyclovir and glucosamine HCl were prepared by an ethanol-based solvent evaporation method. The prepared formulations characterized by photomicroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transforms infrared spectrophotometry (FTIR), powder x-ray diffractometry (PXRD) and drug content analysis. The functional characterization of ACV-SD was performed by aqueous solubility evaluation, dissolution studies, fasted versus fed state dissolution comparison, ex vivo permeability, and stability studies. Photomicroscopy and SEM analysis showed different surface morphologies for pure ACV, glucosamine HCl and ACV-SD. The physical-chemical characterization studies supported the formation of ACV-SD. A 12-fold enhancement in the aqueous solubility of ACV was observed in the prepared solid dispersions, compared to pure ACV. Results from in vitro dissolution demonstrated a significant increase in the rate and extent of ACV dissolution from the prepared ACV-SD formulations, compared to pure ACV. The rate and extent of ACV permeability across everted rat intestinal membrane were also found to be significantly increased in the ACV-SD formulations. Under fed conditions, the rate and extent of the in vitro dissolution of ACV from the formulation was appreciably greater compared to fasted conditions. Overall, the results from the study suggest the feasibility of utilizing glucosamine HCl as a solid dispersion carrier/excipient for enhancement of biopharmaceutical properties of acyclovir, and similar drugs with low solubility/permeability characteristics

Formulation and characterization of organic- inorganic hybrid film for transdermal drug delivery

A novel organic–inorganic hybrid film-forming gel for transdermal application was developed by poly vinyl alcohol using Di methyl polysiloxane as an inorganic-modifying agent, poly N-vinyl pyrrolidone as a tackifier and PEG 200 as a plasticizer. The hybrid film-forming gel can be directly applied on the skin forms a thin bioadhesive film with transparent and non- greasy feeling. The mechanical and bioadhesive properties of films produced from the hybrid gels were investigated and the results showed that the incorporation of appropriate Di methyl polysiloxane into the PVA matrix significantly improves the mechanical strength and skin adhesion properties of the resulting film.  In conclusion, the bioadhesive films formed from organic–inorganic hybrid gel holds excellent qualities for application on the skin and may provide a promising formulation for transdermal delivery of drugs, especially when the patient acceptability from an aesthetic perspective of the dosage form is a main consideration.&nbsp

Formulation and Physical Characterization of Bio-Degradable Chitosan-Poloxamer Gel Base for Local Drug Delivery

Objective: Thermo-modulated in-situ hydrogel (TSHG) are formulated routinely utilizing poloxamer for extended drug release. However physical properties of such formulations may have some flaws, which can be rectified using a combination of polymers with better physical properties such as chitosan. The purpose of the present study was to fabricate biodegradable chitosan-poloxamer-based in-situ drug delivery systems and assessment of their physical properties. Methods: The present chitosan-poloxamer gel base was formulated using a two-stage method. Initially, chitosan gel was prepared by dissolving 1% w/w chitosan in glacial acetic acid. The poloxamer gel was prepared using “cold method”. The final chitosan-poloxamer gel base was prepared by mixing equal amounts of both solutions and evaluated for physical and mechanical properties. Result and Discussion: The DSC thermogram demonstrated no obvious interactions among ingredients or micellization temperature. The gelation temperature of the gel was between 27 and 330C. The pH was 7 with slight clarity. The viscosity of the gel ranged from 15.14 to 41.19 pa.s. The gel was syringable between 4-300C and biodegradable under physiological conditions. The mean particle size of the gel under SEM was found in the range of 300-554 nm. Conclusion: After the evaluation of the formulation, it can be concluded that all the ingredients in the gel showed good compatibility with each other, which could form a stable and homogeneous gel with favorable mechanical and physical properties. Keywords: chitosan, drug delivery system, hydrogels, poloxame

STUDIES ON BIOAVAILABILITY ENHANCEMENT OF CURCUMIN

Objective: The objective of the present work was to improve aqueous solubility and in vivo bioavailability of curcumin and structural analogues of curcumin such as potassium, calcium, magnesium salts and nitro derivative. Methods: Structural analogues of curcumin were prepared by reaction of curcumin with potassium chloride, magnesium chloride hexahydrate and calcium chloride dihydrate in a suitable solvent. The nitro derivative synthesized by treating curcumin with sulphuric acid and nitric acid. The prepared analogues were evaluated for melting behavior, solubility, UV spectrophotometry, partition coefficient, moisture content, cellular uptake, FTIR analysis, antimicrobial activity and in vivo bioavailability in the rat. Results: Chemical modification of curcumin increased the saturation solubility to 11.6, 16.5, 21.5, 28.0 µg/ml in calcium salt, magnesium salt, potassium salt and nitro derivative respectively, against 8.6 µg/ml of curcumin. The analogues were chemically stable as curcumin analyzed by FTIR spectrophotometry. Increased cellular uptake, as well as enhanced antimicrobial activity, was demonstrated by modified curcumin analogues. Moreover, significant improvement in plasma levels was estimated with nitro derivative. Conclusion: The present work recommends that nitration of curcumin improves aqueous solubility which may improve absorption and in vivo bioavailability

DESIGN, FORMULATION AND EVALUATION OF TRANSDERMAL DRUG DELIVERY SYSTEM OF BUDESONIDE

Budesonide is a highly potent synthetic, nonhalogenated corticosteroid. The mechanism of action of corticosteroids in allergic rhinitis remains unknown, but may involve reductions in number of various mediator cells such as basophils, eosinophils, T-helper cells, mast cells, and neutrophils. In the nasal mucosa, nasal reactivity to allergens, and release of inflammatory mediators and proteolytic enzymes. Budesonide is very effective and quikly acting as it is rapidly and almost completely absorbed after oral administration, but has poor systemic availability (about 10%) due to extensive first-pass metabolism in the liver, mainly by the cytochrome P450 isoenzyme CYP3A4.. The major metabolites, 6-β-hydroxybudesonide and 16-α-hydroxyprednisolone have less than 1% of the glucocorticoid activity of unchanged drug with a terminal half-life of about 2-4 hours. Polymeric films containing Eudragit RL 100: Eudragit RS: drug (7:3:1, 7:2:1) and Ethyl cellulose: PVP: drug (7:3:1, 7:2:1) were selected for transdermal administration based on evaluation studies. These polymeric films were prepared by mercury substrate method employing PEG-400 as plasticizer. Two different penetration enhancers Urea and Dimethyl sulphoxide (DMSO) were employed in the study. The patches in each group were uniform in drug content, thickness. In Vitro drug permeation, moisture absorption and WVTR studies were carried out on these test patches. It was found that at all humidity condition the absorption increases which were linear to the moisture absorbed. In PVA and EUDRAGIT RL 100 patches the water vapor transmission rate was found to be higher at 75% RH, RT conditions. Therefore at both % RH, RT condition the PVA and EUDRAGIT RL 100 patches provides the best resistance to water vapor. Therefore, when applied to animals (in further studies) these patches may provide more occlusion to water vapor loss from skin thus making atmosphere beneath the skin more humid that aid in drug permeation

Development And Validation Of First Order Derivative Spectrophotometric Method For Estimation Of Moxonidine In Bulk Drug And Pharmaceutical Dosage Form

A rapid, precise, accurate and specific first-order derivative spectrophotometric method was developed for thedetermination of moxonidine in pharmaceutical formulation. The technique was applied using 0.1M HCl as diluent. Thefirst-order derivative spectra were obtained and determination was made at 232 nm. The method showed good linearity inthe concentration range of 10-50 ?g/ml with correlation coefficient 0.999. The recovery ranged between 99.50 and 100.50%. The proposed method will be suitable for the analysis of moxonidine in bulk and in marketed preparations. The results ofanalysis have been validated statistically and by recovery studies

Evaluation of release retarding property of gum damar and gum copal in combination with hydroxypropyl methylcellulose

The formulations consisting of a hydrophilic and hydrophobic material were investigated for effect on drug-release pattern from the matrices. Gum damar and gum copal being water-insoluble were used to study the efficiency of combined matrices to sustain the release of drug. Hydroxypropyl methylcellulose K100M and diclofenac sodium were used as the hydrophilic material and model drug, respectively. The influence of concentration of hydroxypropyl methylcellulose on drug release pattern of hydrophobic material was determined. The optimum ratio of drug: polymer was found to be 1:1. The hydrophobic:hydrophilic polymer ratio of 75:25 was found to have a similar release pattern as that of marketed formulation. At this ratio, the initial burst-release that occurred in individual hydrophobic matrices was lowered to a great extent. The release of drug was found to follow Higuchi′s equation as the concentration of hydrophobic material was increased. The formulations were compared with marketed formulation Voveran SR, and a correlation was drawn accordingly

Application of Natural Dyes Extracted From Latex Con-taining Plants on Silk Fabric

Colour is one of the most significant factors in the appeal and marketability of textiles products. Identified medicinal value for many of the natural dyes further enhances its popularity and acceptance. The objectives of this study are to study applications of dyes extracted from latex containing plants on silk fabric. Considering the importance and objectives the experimental procedure was designed. The experimental procedure was divided into three phases likely Phase I – Pilot work of the study, exploration of colors, Phase II – Experiment for dye application to develop a colour palate and Test for assessment of Fastness properties and Phase III – Product design and development and its visual assessment for overall impact. From the experiment work and their results we came to the conclusion that the objectives which were framed for the study, get fulfilled satisfactorily