Concentration Of Ethyl Cellulose Research Articles

TRANSDERMAL DELIVERY OF CALCIUM CHANNEL BLOCKER: DEVELOPMENT AND CHARACTERIZATION

Objective: Felodipine, a BCS class II calcium channel blocker, is used in the management of hypertension and angina pectoris. Due to the poor solubility and low bioavailability of the drug, there is a necessity to design an alternative route to achieve a constant plasma concentration of felodipine for its maximum therapeutic utility and can be achieved by transdermal route.Methods: In this study, matrix type transdermal patches were prepared using different combinations of hydrophilic polymer, namely, polyvinylpyrrolidone (PVP) and hydrophobic polymer, namely, ethyl cellulose (EC) by solvent evaporation technique and were subjected for characterization.Results: The Fourier transform infrared studies confirmed the compatibility between drug and polymers. Hydrophilic nature of the polymers greatly influenced physical characteristics and dissolution rate. Equal percentage of PVP and EC yielded patches with good folding endurance. The concentration of plasticizer present in the patches gave them desired folding endurance, and it increased with the presence of hydrophilic polymer. The formulation with highest PVP concentration, F3, exhibited a maximum drug release of 96.23% for 24 hrs. While the formulation with highest EC concentration, F5, exhibited only 74.45% drug release for 24 hrs.Conclusion: From the data, formulation F2 (PVP/EC, 2:1) can be concluded as best formulation due to its desired physical characteristics, good initial drug release, sustained release behavior, and good in vitro permeation. This formulation can be further studied in a clinical scenario.

Formulation of clarithromycin floating microspheres for eradication of Helicobacter pylori

The aim of this study was to develop floating microspheres for gastroretentive delivery of clarithromycin for eradication of Helicobacter pylori. The microspheres were prepared by solvent evaporation using ethyl cellulose (EC) at different weight ratio with clarithromycin with hydroxypropyl methyl cellulose (HPMC E5) acting as secondary polymer. The emulsifier employed either polyvinylpyrrolidone (PVP) or polyvinyl alcohol (PVA). The microspheres were evaluated for floatation, drug entrapment and release, particle size, shape and surface morphology. The physical form of clarithromycin was monitored using FTIR, DSC and X-ray diffraction. The microspheres were in micron range with particle size reducing when replacing PVP with PVA. Further size reduction was recorded in presence of HPMC. The entrapment efficiency increased at high EC concentration especially in presence of HPMC. Immediate floatation was seen with at least 56% of the particles remaining on the surface after 8 h. Physical characterization reflected amorphousization or solubilization of clarithromycin after entrapment in the microspheres. The release pattern followed Higuchi matrix kinetic model in most formulations except those containing low concentration of EC or those containing high HPMC content with HPMC increasing the rate of drug release. The study presented floating microspheres with different release pattern depending on the composition.

DEVELOPMENT AND CHARACTERIZATION OF CONTROLLED RELEASE FAMOTIDINE MATRIX TABLETS CONTAINING COMPLEXES

Objective: The aim of the present study was to formulate the controlled release (CR) tablets of famotidine-cyclodextrin complexes to make the feasibility of complex in CR tablets and to access the kinetic of drug release mechanismMethods: In this work the solubility study of famotidine was performed in various solvents like 0.1 N HCl, phosphate buffer pH 7.4 and distilled water. Enhancement of the solubility and dissolution rate of famotidine was done by complexation with cyclodextrin before formulation into controlled release tablets. Tablets were prepared in different batches by using different concentration of HPMC K15M (hydroxy propyl methyl cellulose) and EC (ethyl cellulose) polymers and polymer blend. All batches were evaluated for pre-compression and post-compression parameters. Release kinetics was analyzed using zero order, first order, higuchi, peppas and hixon-crowell model.Results: All the formulation showed compliance with Pharmacopoeial standards. Release studies indicated that polymer blend (62%HPMCK15M and 38%EC) based matrix tablets with complexed drug was able to control the release of famotidine up to 12 h. Optimized formulation F13 containing complexed drug with same polymer blend showed zero order release and the release mechanism was predominant matrix swelling with erosion.Conclusion: Results of the present study demonstrated that the drug: β-cyclodextrin complex would be a suitable candidate for preparing controlled release tablets of famotidine to improve drug solubility, flow properties and compressibility. Thus the complex used in matrix tablet is a promising approach to achieve appropriate controlled release dosage.

Effects of Organogel Hardness and Formulation on Acceptance of Frankfurters.

Different organogel formulations used as beef fat (BF) replacement (0%, 20%, 40%, 60%, and 80%) were utilized to optimize the mechanical properties of frankfurters. Organogels, made of canola oil (CO), included different concentrations of ethyl cellulose (EC) and sorbitan monostearate (SMS). They consisted of: 8% EC + 1.5% SMS referred to as organogel-I (OG-I), 8% EC + 3.0% SMS (OG-II), and 10% EC + 1.5% SMS (OG-III), which were found promising in a previous study when used at 100% replacement. Replacement of BF with organogels at all levels could bring down the very high hardness values (texture profile analysis and sensory) of frankfurters prepared using CO by itself, relative to the BF control. OG-I and OG-II quantity had no significant effect on hardness and springiness, being similar in many cases to the BF and lower than the CO control. Shear force values of all organogel treatments were not significantly different from one another, and were between the BF and CO controls. Smokehouse yield showed a pattern of decreasing losses with increasing organogel replacement level. Sensory analysis revealed that using CO by itself significantly increased hardness, but structuring the oil (via organogelation), brought it down to the BF control value in all OG-I and OG-II formulations. Juiciness was significantly reduced by using liquid oil but increased with raising the amount of organogels. Oiliness sensation increased with higher organogel substitution and was actually higher than the beef control. The study demonstrates the potential use of vegetable oil structuring in replacing the more saturated BF in emulsion-type meat products.

Potential use of organogels to replace animal fat in comminuted meat products

The replacement of beef fat (BF) with regular or structured canola oil [organogel produced with ethylcellulose (EC) 0.0%, 1.5% or 3.0% sorbitan monostearate (SMS)] was conducted in frankfurters. Substitution with regular oil doubled the hardness of the frankfurters relative to BF. Using an organogel prepared with 8% EC and 1.5 or 3.0% SMS resulted in a hardness value similar to that of BF, by both sensory and texture profile analysis. Without SMS addition, sensory results showed (P<0.05) lower hardness values than regular oil but still higher than BF. Gels prepared using higher EC concentrations (12 and 14%) yielded meat products with a higher sensory hardness than BF (P<0.05). Liquid oil based frankfurters had very small fat globules compared to BF, but structuring the oil yielded larger fat globules. Color measurements indicated that oil-containing frankfurters were lighter than the ones with BF. Smokehouse yields were generally higher for canola oil and organogel containing treatments compared to the beef fat treatment. When SMS was included, fat losses increased over the canola oil treatment. The results demonstrate the possibility to use organogels to replace beef fat and depending on the formulation to manipulate textural properties to resemble traditional products but with lower saturated fat content.

Optimization of fluid characteristics of 2D materials for inkjet printing

ABSTRACT2D materials have shown to be the next step in semiconductor use and device manufacturing that can allow us to reduce the size of most electronics. One of the novel ways to obtain 2D materials is through liquid exfoliation, in which these materials can be obtained by dispersing the smallest possible particles in different solvents. Once obtained, the solutions can be used to manufacture devices via different processes, one of which is inkjet printing. This process relies in selecting “jettable” fluids, which need to have the necessary combination of viscosity and surface energy or “wettability”. In this work we have modified the viscosities and surface energies of five solvents: IPA (Isopropanol), NMP (N-methyl – 2 pyrrolidone), DMA (Dimethylacetamide), DMF (Dimethylformamide) and a mixture of Cyclohexanone / Terpineol 7:3. We have found an avenue to tailor the viscosity of these solvents though the addition of Ethyl Cellulose (EC), where the viscosity has been increased by up to 15 times at an EC concentration of 6%. For inkjet printing, ideally a viscosity of 4 – 10 cP is recommended, which we have been able to achieve with all of the solvents studied. It has been found that the different solvents present different susceptibilities to the EC addition, with DMA and DMF being the least sensitive to the EC addition. We have also studied the change in the drop dynamics and interactions of the 2D solutions with the substrate. Through this analysis we have found solvents that appear to be attractive for inkjet printing of MoS2 and graphite.

Formulation Development of Floating Microspheres of Cefditoren Pivoxel by 32 Factorial Design and in Vitro Characterization

Aim: The main objective of the present research work was to develop floating microspheres of cefditoren pivoxel (CP) to provide the delivery of the drug at a sustained rate. Materials and Methods: Floating microspheres of CP were prepared by solvent evaporation technique using hydroxypropyl methylcellulose (HPMC) K4M and ethyl cellulose as the rate controlling polymers. The optimization of formulation was carried out by 32 factorial design using two factors; a total amount of polymer (X1) and concentration of ethyl cellulose (X2) as independent variables. The formulated floating microspheres were characterized by evaluating its yield, particle size, encapsulation efficiency, in vitro drug release, buoyancy, surface morphology (scanning electron microscopy analysis). Results and Discussion: The optimized formulation (F6) showed 91.5 ± 1.35% of drug release after 12 h and 75 ± 0.92% of entrapment efficiency. All the formulations have good buoyancy which was floated over 12 h in the dissolution medium. Conclusion: It can be concluded from the study that floating microspheres of CP can be prepared successfully using HPMC K4M and ethyl cellulose as the rate controlling polymers.

Formulation and Development of Ethyl cellulose coated Pectin based Capecitabine Loaded Microspheres for Colorectal Cancer

The main objective of present investigation was to design the colorectal microspheres of Capecitabine by using inexpensive natural polysaccharide based polymers. The pectin microspheres were prepared by single emulsification technique using calcium chloride as crosslinking agent. Pectin loaded microspheres were coated with ethyl cellulose by solvent evaporation method. The prepared microspheres were characterized by entrapment efficiency, particle size, in-vitro drug release, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and Differential scanning calorimetry (DSC). The in-vitro drug release behaviour of ethyl cellulose coated pectin microspheres done in varying pH conditions up to 12 hr. Optimized uncoated batch of pectin based capecitabine microspheres showed optimum particle size with good drug encapsulation efficiency and spherical in nature. All the formulations showed less than 20 % drug release in acidic environment. Ethyl cellulose coated microspheres mininised initial burst effect and showed drug release in the range of 85.33 to 95.55% at the end of 12h. As concentration of ethyl cellulose was increased drug release was found to be retarded well. From above results it can be concluded that capecitabine loaded ethyl cellulose coated pectin based microspheres may be the best alternative to conventional tablets to treat the colon cancer.

Facile, Nonhydrothermal, Mass-Producible Synthesis of Mesoporous TiO2 Spheres for Dye-Sensitized Solar Cells

We report a facile, non-hydrothermal (or non-solvothermal) and mass-producible synthesis of mesoporous TiO2 spheres (MTSs) suitable for use in dye-sensitized solar cells (DSSCs). The synthesis is a facile bulk calcination in which the inexpensive polymer ethyl cellulose (EC) is used as a structure-directing agent; the EC concentration is controlled to induce spherical morphology. The size of MTSs can be adjusted by tuning the solute–solvent interactions; for example, the addition of the poor solvent toluene to the solute resulted in the formation of smaller MTSs. A DSSC fabricated using a polymer electrolyte containing ionic liquid and iodine (I2) and using a layer of MTSs on a nanocrystalline (NC) TiO2 layer exhibited an efficiency of up to 6.3%, which is much higher than those of DSSCs with an NC layer only (5.0%) or with a commercial scattering layer (CSL) on an NC layer (5.7%). A solid-state DSSC (ssDSSC) using a single component solid polymer, namely poly((1-(4-ethenylphenyl) methyl)-3-butyl-imidazolium iodide) (PEBII), also exhibited an excellent efficiency of up to 6.4%. The improved efficiency was due to the role of the MTSs in improving surface area and light harvesting properties, as demonstrated by N2 adsorption/desorption isotherm, UV-visible light absorption, reflectance spectroscopy, incident photon-to-current efficiency (IPCE), and electrochemical impedance spectroscopy (EIS) analyses.

Monoglyceride organogels developed in vegetable oil with and without ethylcellulose

We used two commercial monoglycerides (MGs) with different composition (SKB, ≈79% glycerol monostearate and ≈12% glycerol monopalmitate; PKB, ≈47% glycerol monostearate and 47% glycerol monopalmitate) to develop organogels [2% and 8% (wt/wt) MG content]. The objective was to investigate the effect of shearing (SH) and the presence of 6% ethylcellulose (EC) as factors to limit the sub-α to β polymorphic transition of MG, and the subsequent crystals agglomeration that results in deleterious effect on the organogel's mechanical and oil-binding properties. The results showed that under static conditions (ST) both type of MG developed organogels (OG), but their structure, measured as the complex modulus (G*), was weak particularly in the organogels formulated with PKB at 2%. Nevertheless, the OG-ST had higher strength and lower oil loss than the OG-SH. The X-ray analysis showed that the use of shear during organogelation reduced the time at which the sub-α to β polymorphic transition occurred in both the SKB and the PKB oleogels. Additionally, shearing seemed to hinder the formation of well-organized microplatelet structure, and from there the lack of gelation in the 2% OG-SH and the higher oil loss of the 8% OG-SH compared with their static counterparts. Independent of the concentration of SKB and PKB, the presence of EC resulted in organogels with higher G* than that for OG-ST without EC. This, in spite the EC concentration used was below the critical concentration for vegetable oil gelation. The results showed that EC slowed the rate for the sub-α to β polymorphic transition in the MG organogels. Thus, irrespective of the type of MG and the concentration used, during 14days of storage at 15°C the OG-EC systems showed a lower oil loss as a function of time than the corresponding organogels developed without EC. This was particularly evident in the organogels formulated with SKB and those formulated with 8% of MG. We suggest that EC limits the molecular mobility in the MG organogels, and therefore, slows the sub-α to β polymorphic transition and the subsequent β crystals' agglomeration. The results showed that there is a synergistic interaction between MG and EC that result in organogels with higher viscoelastic properties and lower oil loss than those observed in MG-organogels without EC.

The relation between TiO2 nano-pastes rheology and dye sensitized solar cell photoanode efficiency

TiO2 nanoparticle pastes for screen printed semiconductive photoanodes of dye sensitized solar cells were prepared with different content (from 0 to 9wt%) of ethyl cellulose and evaluated by rheology measurements. The effect of ethyl cellulose content in the paste is crucial for printed and sintered TiO2 photoanode properties as thickness, roughness and amount of adsorbed dye, measured by profilometry, atomic force microscopy, IR and UV‐Vis spectroscopy. Moreover, the expressive correlation among paste rheology, layer properties and the final dye sensitized solar cell efficiency depending on the initial ethyl cellulose content was found, including correlations of the properties local maxima positions. The highest efficiency was achieved for the TiO2 paste with 6.5wt% of ethyl cellulose, where initial paste viscosity and thixotropy, printed layer thickness, roughness and amount of adsorbed dye achieved the local maxima (~40Pa.s,4.5µm, 24nm, 1.92×10−8mol/cm2, respectively) that indicates the optimal structure of the oxide photoanode layer. The results confirm the importance of controlled ethyl cellulose concentration and rheological properties of applied pastes for higher DSSC efficiency achievement.

Optimization of diltiazem hydrochloride loaded mucoadhesive floating microspheres using calcium carbonate as gas generating agent as floatation aid

Abstract: Considering the advantages offered by oral prolonged release multiparticulate gastroretentive dosage forms for drugs with narrow absorption window, the objective of this study was to develop mucoadhesive floating microspheres of diltiazem hydrochloride that is anticipated to overcome poor oral drug bioavailability. A 32 full factorial design was employed for optimization wherein concentration of ethyl cellulose and carbopol 934P were chosen as independent variables. Calcium carbonate used as gas generating agent to aid floatation. Percentage buoyancy, mucoadhesion and percentage cumulative drug release for 8 h were taken as dependent variables. A total of nine formulations (F1-F9) were developed by emulsion-solvent evaporation method and evaluated. The particle size, percentage entrapment efficiency, percentage buoyancy, percentage mucoadhesion and percentage cumulative drug release of the optimized formulation (F7) was found to be 160.2±18.87µm, 55.49±1.44%, 84.83±3.89%, 90.66±3.46% and 90.38±1.34% respectively. The in vitro drug release best fitted Higuchi kinetics and the experimental design was validated by extra design check point. DRS revealed no chemical interaction between the drug and polymer used. The spherical shape of microspheres was defined using SEM. DSC and XRD confirmed molecular dispersion of the drug in the microspheres polymeric matrix. The optimized formulation was found to be stable for a period of 3 months. Key words: Diltiazem hydrochloride, mucoadhesive floating microspheres, optimization, stability.

Ethylcellulose nanoparticles with bimodal size distribution as precursors for the production of very small nanoparticles

A common technique for the preparation of polymeric nanoparticles (NPs) from preformed polymers is the emulsification solvent evaporation (ESE) method. However, the particle size of such carriers can typically not reduced below 100 nm. A bimodal distribution of particle size when applying ESE to the preparation of ethylcellulose (EC) NPs was intended to obtain very small particles in a size range below 50 nm. The proportion and size of the small particle fraction (SPF) depended on the surfactant as well as on the EC type and concentration. The preparation was conducted with different pharmaceutically relevant surfactants (polyoxyethylene (23) lauryl ether, sodium dodecyl sulfate, cetyltrimethylammonium bromide, polyvinyl alcohol and polysorbate 20) and all permitted obtaining very small NPs. After purification from excess surfactant by diafiltration and separation of the SPF by centrifugation, monodispersed particles with mean sizes between 20.6 ± 2.3 nm and 49.7 ± 4.8 nm could be isolated. The entrapment of a lipophilic model drug led to encapsulation rates between 34.0 ± 2.4% and 78.2 ± 12.6%, which were size and surfactant dependent. The preparation of polymeric NPs in a size below 50 nm by a simple centrifugation step holds promise for therapeutic applications where larger particles would be inefficient.

Sustained Release Solid Dispersions of Pentoxyfylline: Formulation and Optimization

Objective: The purpose of the study is to formulate and optimize sustained release solid dispersions of pentoxyfylline using a combination of eudragit polymers and ethyl cellulose. Methods: Solid dispersions were formulated by solvent evaporation method.Preliminary batches were formulated using various drug to polymer ratio; with eudragit S100 and L100 (1:1 to 1:5 ratio), and with ethyl cellulose(1:1 to 1:3 ratio) and evaluated for solubility analysis. Based on results of preliminary batches, Box Behnken design was further applied and three factors (X1- concentration of Eudragit S100, X2- concentration of Eudragit L100, X3- concentration of Ethyl Cellulose) were selected with three levels (+1, 0, -1). Multiple linear regression was applied to generate polynomial equations and statistical evaluation. Prepared solid dispersions were investigated for sustained release properties via in vitro dissolution studies. Fourier transform infrared spectroscopic analysis (FTIR), X-ray diffraction analysis (X-RD), Differential scanning calorimetry (DSC) studies were carried out to evaluate drug polymer interactions. Scanning Electron Microscopy (SEM) analysis of optimized solid dispersion was carried out to evaluate surface morphology of the particles. Results: Batch F5 showed maximum sustained release (65.46% in 24 h) characteristics out of all solid dispersions. DSC studies indicated drug integrity when mixed with the polymeric carriers. FTIR and X-RD studies also ruled out any drug polymer interaction. A change in crystalline habit was observed in solid dispersion particles (F5 batch) as seen in SEM micrographs. Polynomial mathematical model generated using multiple regression analysis was found to be statistically significant (p&lt;0.05). Conclusion: Release retarding effect was found to be dependent on polymer concentration. Therefore, an optimized combination may lead to better sustaining effect.

Effect of polydimethylsiloxane and ethylcellulose on in vitro permeation of centchroman from its transdermal patches

This research aims at the development of controlled release contraceptive transdermal patches of centchroman using ethylcellulose (EC) as film-forming polymer, polydimethylsiloxane (PDMS) as pressure sensitive adhesive with propylene glycol and Di-n-butyl-phthalate for their penetration enhancer and plasticizing properties, respectively. The physicochemical compatibility of the drug and the polymers was performed by differential scanning calorimetry and Fourier transform infrared (FTIR) spectroscopic technique. Effects of EC and PDMS ratios on moisture uptake, moisture content, tensile strength (TS), Young’s modulus, adhesive strength, water vapor transmission rate (WVTR) and in vitro permeation of centchroman through Sprague–Dawley rats abdominal skin using Franz’s diffusion cell were evaluated. A 32 full factorial design was employed to observe the effect of independent variables; concentration of ethyl cellulose and PDMS on drug permeated after 32 h, which was selected as dependent variable. Compatibility studies suggested that there were no significant interaction between the drug and polymers used. It was found that incorporation of only EC resulted in too hard patches and addition of PDMS produced patches with lower TS, increased percentage elongation, WVTR and Young’s modulus. Statistical analyses suggested that independent variables have a significant effect on the dependent variable. All formulation follows zero-order release kinetics with r2 > 0.990. In conclusion, drug in adhesive transdermal patches can be successfully fabricated for non-steroidal contraceptive centchroman to obtain a zero-order release systems.

Effect of ethylcellulose on the structure and stability of non-aqueous oil based propylene glycol emulsions

The hydrophobic polymer ethylcellulose (EC) has been used to structure vegetable oils and as a stabilizer of oil/water (o/w) emulsions, among other non food uses. In this work we show that EC dissolved in medium chain triglycerides (MCT) or soybean oil (SO) is able to stabilize non-aqueous emulsions of propylene glycol (PG) as a dispersed phase. Cream-like emulsions can be obtained at both low and high homogenization speeds which show a very good stability for at least one month without the requirement of co-surfactants. PG-in-oil emulsions at concentrations of EC below 5% (w/w) display pseudoplastic behavior and greater viscosity than the respective solutions of the polymer in MCT or SO. However, at concentrations of EC above 5% (w/w) firm gels are formed in MCT or SO and after the addition of PG, the emulsions formed have lower viscosity than the original solutions of the polymer in MCT or SO. Such effects were independent of the mean molecular weight (MMW) of the EC at high shear stress and inversely proportional at low shear stress. These results indicate that the stabilizing effect of EC in PG-in-oil emulsions might not be caused mainly by an increase in the viscosity of the continuous phase. Comparing all the results obtained, we can infer that EC, despite being insoluble in PG, is promoting interactions which are responsible for the observed effects.These PG-in-oil emulsions have interesting structural and flow properties which make them attractive to be used in food formulations, either as emulsions themselves or as potential vehicles for active ingredients.

Effect of Polyvinyl Pyrrolidone and Ethyl Cellulose Concentration on Release Profile and Kinetics of Glibenclamide Extended Release Dosage Form System

Effect of Polyvinyl Pyrrolidone and Ethyl Cellulose Concentration on Release Profile and Kinetics of Glibenclamide Extended Release Dosage Form System

Design and In-vitro Evaluation of Ethyl Cellulose Based Floating Microspheres Containing Antidiabetic Drug

The present investigation was concerned with formulation and evaluation of floating microspheres for Nateglinide using Ethyl cellulose as a release retarded material by solvent evaporation technique. seven different batches of microspheres were prepared by varying the concentration of ethyl cellulose from 0.25% to1.75% The microspheres were characterized for drug content, percentage yield, particle size analysis and surface morphology.The results of all the physiochemical tests of all formulations were found to be favourable. In-vitro floatability studies reveled that most of the microspheres (44 to 95.45%) were floatable. The in-vitro % drug release was found to be in range of 89.18 to 9 . %. at the end of 12 hrs. optimized formulation F4 was evaluated for FTIR, XRD and SEM. XRD and FTIR studies showed that the nature of pure drug Nateglinide remains unaffected till the completion of process of microspheres formation. SEM photographs showed that the Floating microspheres were spherical in nature with smooth surface and uniform distribution of the drug within the microsphere.

Floating microspheres of carvedilol as gastro retentive drug delivery system: 32 full factorial design and in vitro evaluation

Context: Designing a sustained release system for Carvedilol to increase its residence time in the stomach.Objective: Preparation of floating microsphere by the emulsion solvent diffusion method, studying the effect of various process parameters and optimize the formulation using full factorial design.Methods: Different microsphere formulations were prepared by varying the ratio ethanol:dichloromethane (1:0 to 1:1.5), ethyl cellulose:hydroxypropyl methyl cellulose and stirring speed (800–1600 rpm). The effect of these variables on particle size, encapsulation parameters, surface topography, in vitro floatability and drug release were evaluated.Results: 32 full factorial design was used for the optimization of the formulation. Drug entrapment efficiency, particle size and in vitro drug release were dependent on concentration of ethyl cellulose and stirring speed. Microspheres remained buoyant for more than 10 h and showed sustained release of the drug.Conclusion: Floating microspheres of Carvedilol with good floating ability and sustained release were developed.

Design and Characterization of Sustained Release Mucoadhesive Microspheres of Tolterodine Tartrate

The work was aim to design and characterize the sustained release mucoadhesive microspheres of Tolterodine tartrate prepared by non-aqueous solvent evaporation technique using ethyl cellulose based selected mucoadhesive polymers. Selected microspheres formulations of were found to be discrete, spherical and free flowing from the preliminary formulations. The microspheres exhibit good mucoadhesive property in in-vitro wash off test and showed high drug entrapment efficiency. Tolterodine tartrate release from these microspheres was slowed, extended and depended on the concentration of ethyl cellulose and type of mucoadhesive polymer used. In vitro drug release studies suggested that formulation F6c showed consistent drug release for up to 24 h time period. Among all the formulations, F6c containing ethyl cellulose with chitosan showed the reproducible results with best mucoadhesive profile and good surface morphology. The correlation value (r(2)) indicated that the drug release followed Higuchi model. Analysis of variance (ANOVA) showed significant difference in the release of drug from all formulations at P < 0.05 level. Accelerated stability study of optimized formulation (F6c) up to 3 month showed there was no change in drug content and release characteristics during storage.