Formulation of gastroretentive floating drug delivery system using hydrophilic polymers and its in vitro characterization

O objetivo da presente pesquisa é o de formular e avaliar o sistema de liberação de fármaco gastrorretentivo flutuante, contendo o anti-hipertensivo, cloridrato de propranolol. Comprimidos gastrorretentivo flutuantes (GRFT) foram preparados utilizando um polímero hidrofílico sintético, o óxido de polietileno, de diferentes graus, tais como GE WSR N-12 K e GE 18 NF, como polímeros de retardamento de liberação, e carbonato de cálcio, como agente gerador de gases. Os GRFT foram comprimidos por compressão direta e avaliados para determinação das propriedades físico-químicas, flutuabilidade in vitro, estudos de inchamento, de dissolução in vitro e de mecanismo de liberação. Dos testes de dissolução e de flutuabilidade, selecionou-se F 9 como formulação otimizada. A formulação otimizada seguiu cinética de ordem zero, com mecanismo de difusão não-Fickiano. Essa formulação foi caracterizada por estudos de FTIR, não se observando interação entre o fármaco e os polímeros.The aim of the present research is to formulate and evaluate the gastroretentive floating drug delivery system of antihypertensive drug, propranolol HCl. Gastroretentive floating tablets (GRFT) were prepared by using a synthetic hydrophilic polymer polyethylene oxide of different grades such as PEO WSR N-12 K and PEO 18 NF as release retarding polymers and calcium carbonate as gas generating agent. The GRFT were compressed by direct compression strategy and the tablets were evaluated for physico-chemical properties, in vitro buoyancy, swelling studies, in vitro dissolution studies and release mechanism studies. From the dissolution and buoyancy studies, F 9 was selected as an optimized formulation. The optimized formulation followed zero order rate kinetics with non-Fickian diffusion mechanism. The optimized formulation was characterised with FTIR studies and observed no interaction between the drug and the polymers

Photodynamic Therapy – A Non-invasive Treatment Modality for Precancerous Lesions

Introduction: Oral premalignant lesions are conditions having high potential tendency for transformation into malignancy. The use of a conservative and effective treatment modality is one of the best strategies for cancer prevention. Photodynamic therapy (PDT) is a non-invasive method for topical and selective treatment of oral precancerous lesions. The present study was taken up to determine the efficacy of PDT in oral precancerous lesions.Methods: The study consisted 13 patients with 24 oral leukoplakia (OL) lesions and 8 with 20 oral lichen planus (OLP) lesions, divided into control and study groups. These lesions were affecting various intraoral sites, the buccal mucosa being the most common site followed by tongue and gingiva. The treatment regimen of PDT included 98% 5–aminolevulinic acid (5-ALA) which is topical applied and irradiated with light emitting diode (LED) of 420 nm wavelengths at several sessions.Results: In OL 16.6% of cases showed complete response, 66.6% partial response and 16.6% no response of the lesions to the treatment. In OLP 80% and 20% of the lesions showed partial and no response respectively. The differences with control groups for OL + OLP were found to be significant (P < 0.001).Conclusion: Based on the results of the present study, we can conclude that PDT appears to be a feasible alternative to conventional therapy for oral premalignant lesions

Preparation and in vitro characterization of non-effervescent floating drug delivery system of poorly soluble drug, carvedilol phosphate

The objective of the study was to enhance the solubility of carvedilol phosphate and to formulate it into non-effervescent floating tablets using swellable polymers. Solid dispersions (SD)of carvedilol were prepared with hydrophilic carriers such as polyvinylpyrrolidone and poloxamer to enhance solubility. Non-effervescent floating tablets were prepared with a combination of optimized solid dispersions and release retarding polymers/swellable polymers such as xanthan gum and polyethylene oxide. Tablets were evaluated for physicochemical properties such as hardness, thickness and buoyancy. SD prepared with the drug to poloxamer ratio of 1:4 by melt granulation showed higher dissolution rate than all other dispersions. Formulations containing 40 mg of polyethylene oxide (C-P40) and 50 mg xanthan gum (C-X50) were found to be best, with the drug retardation up to 12 hours. Optimized formulations were characterized using FTIR and DSC and no drug and excipient interactions were detected

Design and statistical optimization of an effervescent floating drug delivery system of theophylline using response surface methodology

The aim of this research was to formulate effervescent floating drug delivery systems of theophylline, using different release retarding polymers such as ethyl cellulose, Eudragit® L100, xanthan gum and polyethylene oxide (PEO) N12K. Sodium bicarbonate was used as a gas generating agent. Direct compression was used to formulate floating tablets and the tablets were evaluated for their physicochemical and dissolution characteristics. PEO based formulations produced better drug release properties than other formulations. Hence, it was further optimized by central composite design. Further subjects of research were the effect of formulation variables on floating lag time and the percentage of drug released at the seventh hour (D7h). The optimum quantities of PEO and sodium bicarbonate, which had the highest desirability close to 1.0, were chosen as the statistically optimized formulation. No interaction was found between theophylline and PEO by Fourier Transformation Infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) studies

Design and statistical optimization of an effervescent floating drug delivery system of theophylline using response surface methodology

The aim of this research was to formulate effervescent floating drug delivery systems of theophylline using different release retarding polymers such as ethyl cellulose, Eudragit® L100, xanthan gum and polyethylene oxide (PEO) N12K. Sodium bicarbonate was used as a gas generating agent. Direct compression was used to formulate floating tablets and the tablets were evaluated for their physicochemical and dissolution characteristics. PEO based formulations produced better drug release properties than other formulations. Hence, it was further optimized by central composite design. Further subjects of research were the effect of formulation variables on floating lag time and the percentage of drug released at the seventh hour (D7h). The optimum quantities of PEO and sodium bicarbonate, which had the highest desirability close to 1.0, were chosen as the statistically optimized formulation. No interaction was found between theophylline and PEO by Fourier Transformation Infrared spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) studies

Primary de novo intraosseous carcinoma of the mandible: A rare case report

Primary intraosseous carcinoma (PIOC) is a very rare, but well-recognized entity, which is locally aggressive with quite poor prognosis. It may arise within the jaws either from a previous odontogenic cyst or de novo, rather than from a pre-existing epithelial lesion. A case of PIOC arising in the mandible of a 63-year-old male patient is reported in this article, with the clinical, radiological, and histological features described. This rare lesion must be considered in any differential diagnosis of jaw radiolucency

Investigation on <it>in vitro</it> dissolution rate enhancement of indomethacin by using a novel carrier sucrose fatty acid ester

<p>Abstract</p> <p>Background and the purpose of the study</p> <p>The purpose of the present investigation was to characterize and evaluate solid dispersions (SD) of indomethacin by using a novel carrier sucrose fatty acid ester (SFE 1815) to increase its in vitro drug release and further formulating as a tablet.</p> <p>Methods</p> <p>Indomethacin loaded SD were prepared by solvent evaporation and melt granulation technique using SFE 1815 as carrier in 1:0.25, 1:0.5 1:0.75 and 1:1 ratios of drug and carrier. Prepared SD and tablets were subjected to in vitro dissolution studies in 900 mL of pH 7.2 phosphate buffer using apparatus I at 100 rpm. The promising SD were further formulated as tablets using suitable diluent (DCL 21, Avicel PH 102 and pregelatinised starch) to attain the drug release similar to that of SD.. The obtained dissolution data was subjected to kinetic study by fitting the data into various model independent models like zero order, first order, Higuchi, Hixon-Crowell and Peppas equations. Drug and excipient compatibility studies were confirmed by fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry and scanning electron microscopy.</p> <p>Results</p> <p>The in vitro dissolution data exhibited superior release from formulation S₆ with 1:0.5 drug and carrier ratio using solvent evaporation technique than other SDs prepared at different ratio using solvent evaporation and melt granulation technique. The in vitro drug release was also superior to that of the physical mixtures prepared at same ratio and also superior to SD prepared using common carriers like polyvinyl pyrollidone and PEG 4000 by solvent evaporation technique. Tablets (T₈) prepared with DCL21 as diluent exhibited superior release than the other tablets. The tablet formulation (T₈) followed first order release with Non-Fickian release.</p> <p>Conclusion</p> <p>SFE 1815 a novel third generation carrier can be used for the preparation of SD for the enhancement of <it>in vitro</it> drug release of indomethacin an insoluble drug belonging to BCS class II.</p

FORMULATION OPTIMIZATION, SCALE UP TECHNIQUE AND STABILITY ANALYSIS OF NAPROXEN LOADED LIPOSPHERES

The objective of this research was to formulate the anti-inflammatory drug (naproxen) to provide controlled release and minimizing local side effect by avoiding the drug release in the stomach region. Naproxen was entrapped with lipid-like cetyl alcohol, glyceryl mono stearate and stearic acid using melt dispersion technique. Effect of various formulation and process variables such as concentration of surfactant, concentration of co-surfactant, on formulation parameters such as morphology, entrapment efficiency, and in vitro release of naproxen were studied. The lipospheres were characterized for particle size, photo microscopy, scanning electron microscopy, FT-IR spectroscopy, drug entrapment efficiency, in vitro release studies, and in vitro release kinetics. The shape of microspheres was found to be spherical, drug entrapment efficiency of various batches of microspheres was found to be ranging from 80 to 90 %. The in vitro drug release studies of optimized batches were carried out for up to 24 h using phosphate buffer pH 7.4 showed 80-85% drug release. The optimized formulation batch was considered for scale up process. The lipospheres obtained from the scale up were then characterized for particle size, drug loading and morphology and compared with non-scaled up optimized batch, thereby establishing successful process scale-up. Key words: naproxen, liposphere, scale up technique, optimization, encapsulation efficienc

Herpes zoster infection: Report of a treated case

Herpes zoster (HZ) is an acute infectious viral disease result from reactivation of the DNA varicella-zoster virus, which occurs more frequently among older adults and immunocompromised persons. The most common complication of HZ is postherpetic neuralgia, a chronic often debilitating pain condition that can last months or even years. Deaths attributable to zoster are common among immunocompromised persons. Prompt treatment with the antiviral drugs, corticosteroids and analgesics decrease the severity and duration of acute pain from HZ. Here, we report a treated case of HZ in 35-year-old male involving all three branches of the trigeminal nerve without any complication