Formulation optimization and analysis of taste-masking effect of licorzine granules based on sensory evaluation and electronic tongue method / 药学学报

Licorzine granules are common preparations for children zinc deficiency. Considering the long course of treatment, the taste of licorzine granules may become a main factor affecting medication adherence. To date there have been no taste evaluation research into licorzine granules yet. In this study, both sensory evaluation and electronic tongue method were utilized to optimize licorzine granules formulations, evaluate the tastes of licorzine, excipients, optimized formulation in vivo and in vitro. As the results show, bitterness and astringency are the main unpleasant tastes generating from licorzine. Xanthan gum is the main taste-masking excipient, lowering down the bitterness and astringency of licorzine by at least one grade. Good correlation exists between the results of sensory evaluation and electronic tongue method, and an integrated combination of the two helps to obtain objective and rational research conclusions. The adult sensory evaluation study was a research-based clinical trial conducted with informed consent from all subjects in accordance with the ethical requirements of Good Clinical Practice.

Optimisation of topical antibacterial preparation from Malaysian kelulut honey by using xanthan gum as polymeric agent

@#The study aims to formulate and optimise topical antibacterial preparation by using Malaysian kelulut honey as the active ingredient and xanthan gum as the polymeric agent. Response surface methodology was used to optimise the preparation. The acidity, honey concentration and xanthan gum concentration were the independent variables. The zone of inhibitions on S. aureus ATCC6538 and E. coli ATCC8739 were the response variables. The optimal preparation was evaluated on its physicochemical properties, viscosity, antibacterial efficacy and stability. The antibacterial efficacy of the optimal preparation was compared to the commercially antibacterial gel (MediHoney™, Comvita). The optimal preparation was formulated at pH of 3.5, honey concentration of 90% (w/v) and xanthan gum concentration of 1.5% (w/v) with the inhibition zones measured on S. aureus ATCC6538 was 16.2 mm and E. coli ATCC8739 was 15.8 mm respectively. The factors of acidity and honey concentration have significantly influenced the inhibition zone on S. aureus ATCC6538 and E. coli ATCC8739. The utilisation of xanthan gum as the polymeric agent was fit for the preparation which showed by adequate physicochemical properties and retained of the antibacterial effects. This was supported by constant viscosity and efficacy of the preparation within the six months of stability study indicating stable and reliable preparation. Xanthan gum is a potential polymeric agent due to its effective use in preparing stable preparation with effective antibacterial properties.

Formulation And Evaluation Of Racecadotril Mucoadhesive Microspheres

Objective: To develop and evaluate the mucoadhesive microsphere using combinations of natural polymers chitosan and xanthan gum for sustained release. Methods: In the present work mucoadhesive microspheres were prepared by using natural polymers like chitosan and xanthan gum by using the emulsion chemical cross-linking method. Chemical cross-linking was done by using glutaraldehyde. The 22 factorial design was employed to show the effect of cross-linking agent and processing factor-like stirring and speed. Prepared microspheres were evaluated for their particle size, surface morphology, drug entrapment efficiency, in vitro drug release, swelling index, and mucoadhesive strength. Results: The size of microspheres of factorial batches were in the range of 26-46 µm. The swelling index was showed in the range of 1.51-1.66 percentage. The equation of multiple regression revealed that there was significant interaction among factors. The glutaraldehyde concentration had a positive effect on % entrapment efficiency, % cumulative drug release and % mucoadhesion. Stirring speed showed a negative impact on % entrapment efficiency, % cumulative drug release and % mucoadhesion. The interactive effect of glutaraldehyde concentration and the stirring speed was found to be positive for % entrapment efficiency and % cumulative drug release. In vitro drug release study of optimized formulation F2 show 96 % of drug release with 6 h indicating sustained release behavior with diffusion mechanism. The SEM image of the optimized batch was spherical with a porous surface. Conclusion: The results obtained in this research work indicated that a promising potential of chitosan and xanthan gum combination for the preparation of the mucoadhesive microsphere of Racecadotril.

Biopolymer Xanthan: A New Adjuvant for DNA Vaccines

Abstract DNA vaccines have been evaluated as an option to prevent several diseases. In this study, the capacity of the xanthan biopolymer to improve the DNA vaccines immune response, administered intramuscularly, was evaluated. The experimental vaccines consisted of genes encoding fragments of the proteins LigA and LigB of Leptospira interrogans serogroup Icterohaemorrhagiae serovar Copenhageni strain Fiocruz L1-130. The humoral immune response was evaluated by indirect ELISA. Cytokine expression levels were determined by RT-qPCR. Compared to the control group, the IgG antibody levels of animals immunized with pTARGET/ligAni and pTARGET/ligBrep plasmids associated with xanthan biopolymer were significantly higher than the control group. Additionally, there was a significant increase in IL-17 expression in animals vaccinated with pTARGET/ligBrep and xanthan.

Application of Films Based on Chitosan and Xanthan Gum in Refrigerated Fish Conservation

Abstract This research aims to determine the efficiency of chitosan and xanthan gum films in conservation of croaker fillets kept in refrigeration for 9 days. Proximal composition, loss of mass, color, pH, TVB-N (Total Volatile Bases) and microbiological profile were assessed. The films were prepared with chitosan and xanthan gum in varying mass proportions 100:0, m:m (C100XG0); 60:40, m:m (C60XG40); 50:50, m:m (C50XG50). They presented the respective values for moisture content, water solubility, thickness and water vapor permeability: 24.59%, 19.50%, 0.086 mm and 11.45gm-1.s-1.Pa-1for C100XG0; 24.58%; 20.27%, 0.091 mm and 10.41 gm-1.s-1.Pa-1for C60XG40; 22.11%, 22.06%, 0.089 mm and 10.68 gm-1.s-1.Pa-1 forC50XG50.The films were made in small bags format capable to hold about 20 g of fish fillets. A control sample was prepared in parallel, using polyethylene bags under the same storage conditions. The results showed that the chitosan films combined with xanthan gum had excellent antimicrobial properties, capable of preserving the quality of chilled fish fillets during the studied period, since it inhibited the growth of Staphylococcus coagulase-positive, Salmonella spp and coliforms at 45 ° C. Mass loss of the croaker fillets was not significantly affected by xanthan gum addition to the films. On the other hand, xanthan gum addition affected pH and color parameters of the corvina fillets. It was also verified that the combination of these two polymers promoted the reduction of N-BVT, being the C50XG50 film that presented the best response.

Hidrocoloides como estabilizantes en bebidas de maíz dulce (Zea mays var. saccharata) y gel de aloe vera ( Aloe barbadensis Miller) / Hydrocolloids as stabilizers in beverages from sweet corn (Zea mays var. Saccharata) and aloe vera gel (Aloe barbadensis Miller)

RESUMEN La sedimentación de partículas es un fenómeno común en dispersiones alimentarias, que está asociado con una calidad deficiente y se puede controlar usando diferentes aditivos, dentro de los cuales, se destacan el uso de hidrocoloides. Se evaluó el efecto de la concentración de goma xantano (0,025-0,075%), carboximetilcelulosa sódica (0,025-0,075%) y gel de aloe vera (0,5-1,5%), en las propiedades fisicoquímicas, sensoriales y estabilidad a la sedimentación, en bebidas elaboradas a partir de maíz dulce. No se observó variación significativa en el contenido de sólidos solubles totales, pH, densidad, acidez titulable, potencial ζ, tamaño de partículas, velocidad de sedimentación y parámetros de color con las concentraciones empleadas de hidrocoloides y de aloe vera. El potencial ζ indicó estabilidad ligera en las bebidas (>-30mV) y la floculación de la emulsión, lo que se evidencia en la distribución del tamaño de partícula (1-600μm). La viscosidad y la estabilidad a la sedimentación aumentaron con concentraciones >0,05% de GX y CMC, reflejándose en una mayor valoración sensorial de la apariencia. El aumento en la concentración de aloe vera no mostró efecto en la estabilidad de las bebidas.

ABSTRACT Particle sedimentation is a common phenomenon in food dispersions, which is associated with poor quality and can be controlled using different additives within which the use of hydrocolloids stands out. The effect of the concentration of xanthan gum (0.025-0.075%), sodium carboxymethylcellulose (0.025-0.075%) and aloe vera gel (0.5-1.5%), on physicochemical, sensory properties and sedimentation in beverages made from sweet corn, were evaluated. No significant variation was observed in the content of total soluble solids, pH, density, titratable acidity, ζ potential, particle size, sedimentation index and color parameters with the concentrations of hydrocolloids and aloe vera. The potential ζ indicated slight stability in beverages (> -30mV) and emulsion flocculation, which is evidenced in the particle size distribution (1-600μm). The viscosity and sedimentation stability increased with concentrations >0.05% of GX and CMC, reflected in a higher sensory assessment of appearance. The increase in aloe vera concentration showed no effect on the stability of the beverages.

Gene expression analysis identifies hypothetical genes that may be critical during the infection process of Xanthomonas citri subsp. citri

Background: Gene expression analysis via microarray is widely used in phytobacteria to validate differential gene expression associated with virulence or to compare biological profiles of wild type and mutant strains. Here, we employed DNA microarrays to study the early stages of the infection process (24, 72 and 120 h post-inoculation) of Xanthomonas citri subsp. citri (Xac) infecting Citrus sinensis to interrogate the expression profiles of hypothetical genes. Results: Under infective conditions, 446 genes were up- and 306 downregulated. Outstanding among genes upregulated during infection were those involved in synthesizing the Type 3 Secretion System and effectors, xanthan gum and quorum-sensing induction, and flagellum synthesis and regulation. Additionally, 161 hypothetical genes were up- and 100 were downregulated, 49 of which are known to have a significant biological role. To understand hypothetical gene co-regulation or -expression, nine expression profiles including 158 genes were identified during the three infection phases. Of these, 47 hypothetical genes were identified as having expression profiles associated with at least one connected to a gene associated with adaptation and virulence. Conclusions: Expression patterns of six differentially expressed genes were validated by quantitative reverse transcription polymerase chain reaction, thus demonstrating the effectiveness of this tool in global gene expression analysis in Xac.

Colon targeted tablets of Albendazole with enhanced solubility by Complexation and Micellar Solubilization

Albendazole (AZ) is a drug used for the treatment of gastrointestinal nematode infections. Phase solubility study was performed to investigate the optimized ratio of AZ: β-cyclodextrin (β-CD) solid dispersion (SD). Increase in the solubility of optimized AZ: β-CD SD was further enhanced by addition sodium lauryl sulfate (SLS) in different ratios was studied. Matrix tablets of the optimized ratio of AZ: β-CD SD with SLS and various proportions (10%, 15%, and 20%) of guar gum (GG). xanthan gum (XG) and pectin (PT) were prepared by non-aqueous wet granulation with PVP K30. Standard calibration curve for AZ was performed in three buffers like 0.1 N HCl, pH 6.8 phosphate buffer solution (PBS) and pH 7.4 PBS and absorbance were measured at 295 nm. Tablets were evaluated for various physical characteristics such as thickness, hardness, and drug content uniformity. The matrix tablets were subjected to in vitro drug release studies in 0.1 N HCl (2 h), pH 6.8 PBS (3 h) and pH 7.4 PBS (19 h) with and without rat caecal content medium. Formulation F9 shows 70.65% and 95.62% of AZ in with and without rat caecal content media respectively is selected as optimized one. Optimized formulation F9 passed the test for stability up to 3 months as per ICH guidelines.

Injectable in situ gel of methotrexate for rheumatoid arthritis: Development, in vitro and in vivo evaluation

The aim of the research study was to formulate a novel, biodegradable, injectable in situ gel system of Methotrexate(MTX) in the management of rheumatoid arthritis (RA). Varying concentration of Pluronic F-127 (20% and 22% w/v)and xanthan gum (0.2%–0.6% w/v) were used in the development of the formulations. In vitro and in vivo studieswere carried out for the prepared MTX in situ gels. The results demonstrated that MTX was uniformly distributed andthe in situ gels were sterile and syringeable. The gels showed thermosensitivity and thermoresponsivity dependenton concentration and composition of co-polymers. The optimized formulation exhibited drug release of 95.29% at132 hours by non-fickian diffusion mechanism. Polymer concentration and composition influenced the release of thedrug from the prepared in situ gels. In vivo studies carried on Freund’s adjuvant-induced monoarthritis in male Wistarrats; results showed a significant reduction in the inflammation at the test site. The gels were biocompatible since noinflammation was observed in the synovial membrane. MTX in situ gels could be proposed as an effective deliverysystem management of RA in near future.

Evaluation of Cissus populnea gum as a directly compressible matrix system for tramadol hydrochloride extended-release tablet

The aim of this study was to evaluate and compare the compactibility, mechanical and release properties of tramadoltablets prepared by direct compression using cissus gum, a naturally occurring plant polymer as directly compressibleexcipient in comparison with xanthan gum. Compactibility was measured by Heckle, mechanical properties by tensilestrength and friability, and release properties by dissolution profile. Student t-test with GraphPad Prism 5 was used toidentify differences between data at p < 0.05. The result showed that the Py of xanthan formulation was significantlylower than cissus formulations (p = 0.03). Onset of plastic deformation was directly dependent on the concentrationof the polymer and the properties of the active ingredient. The presence of the active ingredient retarded the onsetof plastic deformation. There was increase in crushing strength and tensile strength with decrease in friability as theconcentration of the polymer increased in all formulations. The mechanical properties of cissus gum and xanthan gumformulations were not significantly different (p > 0.05). Tramadol dissolution decreased as the concentration of thepolymers increased. Cissus gum has some properties that would make it suitable as direct compressible excipient inmatrix systems for extended-release.

Application of agar thickener in dysphagia after radiotherapy for nasopharyngeal carcinoma / 中华物理医学与康复杂志

Objective To compare a new agar thickener with xanthan gum as a thickener in treating dyspha-gia patients with nasopharyngeal carcinoma after radiotherapy. Methods Twenty nasopharyngeal carcinoma patients with dysphagia after radiotherapy were asked to swallow moderately and extremely thick liquids thickened with the agar and xanthan gum, and their swallowing was recorded with a videofluoroscope. Results The average pharyngeal con-striction ratio when swallowing agar thickener was significantly lower than when swallowing the traditional thickener. The average oral transit time, the initiation of pharyngeal swallowing were both significantly quicker. There was no sig-nificant difference in the average penetration aspiration scale scores between the two thickeners. In the subjective eval-uation, the agar thickener was adjudged smoother and with better residual mouthfeel than the xanthan gum, but the scent of the xanthan gum was preferred. Conclusion The new agar thickener is smooth and not sticky. It produces faster transport with less oropharyngeal residue. It can be widely used among nasopharyngeal carcinoma patients with dysphagia after radiotherapy.

Application of agar thickener in dysphagia after radiotherapy for nasopharyngeal carcinoma / 中华物理医学与康复杂志

Objective@#To compare a new agar thickener with xanthan gum as a thickener in treating dysphagia patients with nasopharyngeal carcinoma after radiotherapy.@*Methods@#Twenty nasopharyngeal carcinoma patients with dysphagia after radiotherapy were asked to swallow moderately and extremely thick liquids thickened with the agar and xanthan gum, and their swallowing was recorded with a videofluoroscope.@*Results@#The average pharyngeal constriction ratio when swallowing agar thickener was significantly lower than when swallowing the traditional thickener. The average oral transit time, the initiation of pharyngeal swallowing were both significantly quicker. There was no significant difference in the average penetration aspiration scale scores between the two thickeners. In the subjective evaluation, the agar thickener was adjudged smoother and with better residual mouthfeel than the xanthan gum, but the scent of the xanthan gum was preferred.@*Conclusion@#The new agar thickener is smooth and not sticky. It produces faster transport with less oropharyngeal residue. It can be widely used among nasopharyngeal carcinoma patients with dysphagia after radiotherapy.

Effect of ph on the stability of red beet extract (Beta vulgaris l.) microcapsules produced by spray drying or freeze drying

Abstract Red beets is rich in phenolic acids and has high antioxidant capacity, and can be used to produce a natural dye. This study evaluated the effect of pH (3 to 6) on the stability of red beet extract microcapsules, dried by freeze drying and spray drying and stored at room temperature. The microcapsules were produced using a combination of maltodextrin and xanthan gum as encapsulating agents and stored for 7 days. For all evaluated microcapsules, a degradation of betanin was observed, however, that degradation was independent of pH, with the exception of the sample with maltodextrin and dried by spray drying. The freeze dried products showed lower degradation constants and higher half-life (t1/2) when comparing with the spray dried samples. The microcapsules containing maltodextrin and xanthan gum, dried by spray drying, showed the highest change in the content of phenolic compounds after storage for 7 days. The color parameters showed a reduction for a*, and increase in b* and L*, for all samples during the storage time. In general, the microcapsules produced using maltodextrin and xanthan gum, and dried by freeze dryer, showed higher stability in terms of betanin content, phenolic compounds and color parameters during storage at different pHs.

Effect and mechanism of xanthan gum on osteoarthritis caused by anterior cruciate ligament transection / 药学学报

The study is designed to evaluate the protective effect of xanthan gum (XG) injection on cartilage injury in the rabbit osteoarthritis (OA) model induced by anterior cruciate ligament transection (ACLT), and to explore the effect of XG on the expression of caspase-3 and Bax protein in OA cartilage. Sixty male New Zealand white rabbits were randomly divided into 6 groups (n=10) according to random number table method, and one group was selected randomly as the normal control group (control) while the other 5 groups of right knee were used to establish the OA model with ACLT, which were then divided into model group (model), XG-0.6 mg·kg-1, XG-1.2 mg·kg-1, XG-2.4 mg·kg-1 treatment group and sodium hyaluronate (SH-1.2 mg·kg-1) treatment group according to drug intervention. The knee joint temperature and knee joint width of each group were measured in the course of treatment. After treatment, the macroscopic morphology of rabbit joints in each group was observed. The pathological morphology of articular cartilage of rabbits in each group was observed using HE staining. The expression of Bax and cleaved caspase-3 in the cartilage of rabbits were detected by Western blot. The result shows that XG inhibited the increase in knee joint temperature and knee width caused by OA in a dose-dependent manner. XG improved the morphological abnormalities and tissue injuries of the femoral condyle and tibial plateau caused by OA. Western blot result shows that, compared with the control group, the levels of Bax and cleaved caspase-3 in knee cartilage cells of model group and XG-0.6 mg·kg-1 group were significantly increased (P-1 group (P>0.05). These two groups are significantly higher than those of XG-1.2 mg·kg-1 and XG-2.4 mg·kg-1 (P-1 and XG-1.2 mg·kg-1 group (P>0.05). The level of Bax in knee cartilage in XG-2.4 mg·kg-1 group was lower than that of XG-1.2 mg·kg-1 group (P<0.05). In conclusion, XG effectively protected cartilage damage in OA, and inhibited the expression of Bax and caspase-3 protein in OA cartilage.

Preparation of Triamcinolone Acetonide Acetate Thermosensitive Hydrogel and Its In Vitro Release / 医药导报

Objective To prepare triamcinolone acetonide acetate(TAA)thermosensitive hydrogel for intra-articular injection,and to investigate its release in vitro. Methods TAA suspending thermosensitive hydrogel was prepared by using poly lactic-co-glycolic acid(PLGA)-polyethylene glycol(PEG)-PLGA as gel matrices,xanthan gum as suspending agent and NaCl as flocculant. It was evaluated preliminarily by determining its contents and its in vitro release. Results The best compositions for preparation of TAA suspending thermosensitive hydrogel were 25% PLGA-PEG-PLGA,0.05% xanthan gum, 0.9% NaCl and 4 mg·mL-1 TAA.The gelation temperature was 35.3 ℃ .The average recovery was(98.98±0.31)%. By the method of membraneless dissolution,the accumulative drug release was up to 83. 31% at 16 days. The drug release followed Ritger-Peppas methematical model. Conclusion The TAA thermosensitive hydrogel with obviously sustained release is expected to become a new drug delivery system for intra-articular injection.

Design and optimization of novel in situ gel of mercaptopurine for sustained drug delivery

Mercaptopurine is a purine antagonist, belonging to the class of antimetabolites. Its oral absorption is erratic and variable throughout GIT, with bioavailability of 5-37% and belongs to Biopharmaceutical Classification System (BCS) class IV. The focus of the present study was to improve solubility of mercaptopurine and to release the drug uniformly throughout the GIT by formulating into a novel in situ gel tablet. By in vitro swelling studies, xanthan gum was selected as the best gelling polymer and the tablets were prepared by direct compression. Sodium chloride was used as a release modifier to improve the release of drug from the tablet. A 32 full factorial design was applied to optimize the percentage of xanthan gum and sodium chloride to get desired swelling index and release profile. Tablets were evaluated for weight variation, hardness, friability, disintegration time, drug content, in vitro swelling studies and in vitro dissolution studies. The best optimized formulation showed good swelling index and extended the release up to 12 h, where as conventional tablet released the drug within 45 min. The results indicate that mercaptopurine loaded in situ gel tablet could be effective in sustaining drug release for a prolonged period of time throughout the GIT, which can possibly improve the oral bioavailability.

Mercaptopurine é um antagonista da purina, pertencente à a classe dos antimetabólitos. A sua absorção oral é errática e variável através do TGI, com biodisponibilidade de 5-37 % e pertence à classe IV, de acordo com o Sistema de Classificação Biofarmacêutica. O foco do presente estudo foi melhorar a solubilidade da mercaptopurina e liberar o fármaco uniformemente através do TGI, por meio da nova formulação de comprimidos que se tornam gel in situ. Por meio de estudos de inchamento, a goma xantana foi selecionada como o o melhor polímero gelificante e os comprimidos foram preparados por compressão direta. O cloreto de sódio também foi usado como agente modificador de liberação para aprimorar a liberação do fármaco do comprimido. Aplicou-se planejamento fatorial 32 para otimizar a porcentagem de goma xantana e de cloreto de sódio para se alcançar o índice de inchamento e o perfil de liberação desejáveis. Os comprimidos foram avaliados quanto à variação de peso, dureza, friabilidade, tempo de desintegração, conteúdo de fármaco, estudos in vitro de inchamento e de dissolução. A formulação mais bem otimizada mostrou bom índice de inchamento e liberação prolongada acima de 12 h, em comparação com um comprimido convencional, que libera o fármaco em 45 minutos. Os resultados indicam que a 6-mercaptopurina carregada no comprimido de gelificação in situ poderia ser eficaz para a liberação controlada por período de tempo prolongado através do TGI, o que pode, possivelmente, aprimorar a biodisponibilidade oral.

Development of natural gum based glipizide mucoadhesive microsphere.

The objective of this study was to develop glipizide microsphere with natural gums. Guar gum and xanthan gum were used separately in different ratios as natural polymers. The microspheres were prepared by orifice ionic gelation method and they were characterized by scanning electron microscopy and particle size analysis. Among six formulations, microspheres of four formulations (F1-F4) were discrete, sphrerical and free flowing. There was an inverse relationship found between the amount of gum and surface smoothness in case of guar gum-containing microspheres while a forward relationship was found between amount of gum and surface smoothness in case of the microspheres containing xanthan gum. The size of the particles increased with increasing amounts of gum. It can be concluded that guar gum and natural gum at a ratio of 1:0.25 and 1:0.5 can be ideal for formulating natural gum based glipizide mucoadhesive microsphere.

Screening of mucoadhesive vaginal gel formulations

Rational design of vaginal drug delivery formulations requires special attention to vehicle properties that optimize vaginal coating and retention. The aim of the present work was to perform a screening of mucoadhesive vaginal gels formulated with carbomer or carrageenan in binary combination with a second polymer (carbomer, guar or xanthan gum). The gels were characterised using in vitro adhesion, spreadability and leakage potential studies, as well as rheological measurements (stress and frequency sweep tests) and the effect of dilution with simulated vaginal fluid (SVF) on spreadability. Results were analysed using analysis of variance and multiple factor analysis. The combination of polymers enhanced adhesion of both primary gelling agents, carbomer and carrageenan. From the rheological point of view all formulations presented a similar behaviour, prevalently elastic and characterised by loss tangent values well below 1. No correlation between rheological and adhesion behaviour was found. Carbomer and carrageenan gels containing the highest percentage of xanthan gum displayed good in vitro mucoadhesion and spreadability, minimal leakage potential and high resistance to dilution. The positive results obtained with carrageenan-xanthan gum-based gels can encourage the use of natural biocompatible adjuvants in the composition of vaginal products, a formulation field that is currently under the synthetic domain.

O planejamento racional de formulações para a liberação vaginal de fármacos requer atenção especial às propriedades do veículo, que otimizem o revestimento e a retenção vaginal. O objetivo do presente trabalho foi realizar uma triagem de géis vaginais mucoadesivos formulados com carbomero ou carragenina em combinação binária com um segundo polímero (carbomero, goma guár ou xantana). Os géis foram caracterizados usando estudos in vitro de aderência, espalhabilidade e potencial de vazamento, bem como medições reológicas (testes de varredura de tensão e frequência) e o efeito de diluição com fluido vaginal simulado (SVF) na espalhabilidade. Os resultados foram analisados utilizando a análise de variância e de fator múltiplo. A combinação de polímeros reforçou a adesão de ambos os agentes gelificantes primários, carbomero e carragenina. Do ponto de vista reológico todas as formulações apresentaram comportamento semelhante, predominantemente elástico e caracterizado por valores de tangente de perda bem abaixo de 1. Não se encontrou correlação entre as medições reológicas e o comportamento de adesão. Os géis de carbomero e carragenina contendo o maior porcentual de goma xantana apresentaram melhor mucoadesão e espalhabilidade, menor potencial de vazamento e maior resistência à diluição in vitro. Os resultados positivos obtidos com géis de carragenina-goma xantana podem incentivar o uso de adjuvantes biocompatíveis naturais na composição dos produtos vaginais, um campo de formulação atualmente sob o domínio de produtos sintéticos.

Formulation development and evaluation of voriconazole sustained release tablets.

The present study involves in the formulation and evaluation of sustained release tablets of Voriconazole (250mg). The objective of the present study was to formulate Voriconazole sustained release tablets by wet granulation method by using natural (Xanthan gum, Karaya gum) and semi synthetic polymers (HPMC K100M). Lactose was used as diluting agent, Magnesium stearate was used as a lubricant and Talc was used as a glident. These sustained release tablets can release the drug up to 12 hours in predetermined rate. The formulated powder blend was evaluated for bulk density, tapped density, compressibility index and angle of repose. The formulated tablets were evaluated for physical characteristics of sustained release tablets such as thickness, hardness, friability, weight variation and drug content. The results of the formulations found to be within the limits specified in official books. The tablets were evaluated for In-vitro drug release studies by using USP type I dissolution test apparatus. The dissolution test was performed in 0.1 N HCL for 2 hr and phosphate buffer pH 6.8 for 10hrs. The in-vitro cumulative drug release profile of all formula-tions F1-F10 at 12 hours showed 84.25% to 99.82% drug release, respectively. From the data it was clear that by increasing the amount of polymer in the formulation the amount of drug release was decreased. Hence, Formulation F9 was the most promising formulation as it gives satisfactory release (99.82%) for 12 hours and F9 found to be the best formulation.

Design and Development of Atenolol Matrix Tablet Employing Natural and Synthetic Polymers.

The main objective of the present work was to develop sustained release matrix tablets of Atenolol. To reduce the frequency of administration and to improve the patient compliance, a once daily sustained release formulation of Atenolol is desirable. So sustained release Matrix Tablet of Atenolol was designed by using different polymers viz.Starch, Xanthan Gum, Vee Gum , Guar Gum, Gum Accacia, Tragacanth, Hupu Gum were used as natural polymers and Eudragit-L100, Ethyl Cellulose, Sodium Carboxy Methyl Cellulose (Na-CMC) ,Hydroxy Propyl Methyl Cellulose (HPMC) (5&15cps), Methyl Cellulose, Kollidon were used as synthetic polymers. After fixing the ratio of drug and polymer for control the release of drug up to desired time, the release rates were modulated by Single polymer, combination of two different rates controlling material. The FT-IR study revealed that there was no chemical interaction between drug and excipients. The granules were prepared by dry granulation method. Precompressional parameters i.e. angle of repose, percent compressibility, and Hausner’s ratios were studied. These results indicate that granules are good flowing characteristics. After evaluation of physical properties like Weight variation, Hardness, Thickness, Friability of tablet, the different formulations checked for the Percentage Drug content which having good uniformity. The results of drug dissolution studies showed improved drug release, retardation effects of the polymers and could achieve better performance. After eight hours dissolution test, dissolution profiles showed that better sustained release was observed from starch and veegum containing formulation and eudragit and ethyl cellulose containing formulation of atenolol matrix tablet. It was also observed that the presence of starch caused an increase in the release rate of atenolol matrix tablet. The present study shows a relatively simple method to design and develop Atenolol matrix tablet.