Hydroxypropyl Methylcellulose K100 Research Articles

Optimization of simvastatin transdermal patch for hyperlipidemia treatment in rat model

ObjectiveBiopharmaceutics Classification System says that simvastatin (SMV) is a Class II drug with low bioavailability (5%). This is because it dissolves slowly and is broken down a lot in the first pass. Simvastatin transdermal patches were produced as part of this study's aim to treat hyperlipidemia. The Box–Behnken design (three-factor, three-level) was selected for optimization of patches.MethodologyThe optimization design involved 15 runs with independent factors hydroxypropyl methylcellulose K100, Eudragit L100, and polyethylene glycol 400 percentage, and dependent factors including folding endurance and in-vitro drug release.ResultsThe results showed that the concentration of hydroxypropyl methylcellulose K-100 positively impacted the patch’s folding endurance. The fact that factor C was the only scenario where the p-value was less than 0.05 and the coefficient value was higher in the in vitro drug release model means that it has a greater influence on the release of medicines. The patches were also evaluated for drug content, swelling, moisture uptake, moisture content, etc. The optimized patch shows an in vitro drug release of 55.3% in up to 24 h. In vivo antihyperlipidemic activity was evaluated in albino Wistar rats. In the standard treatment (simvastatin oral) groups, there is a decrease in cholesterol (132.76 ± 0.35) and triglyceride level (139.80 ± 76) whereas in the test formulation group or test group, there is also a decrease in cholesterol (169.65 ± 0.21 mg/dL) and triglyceride level (151.20 ± 31 mg/dL) level.ConclusionBased on in-vitro and in-vivo results it can be concluded that simvastatin patches can be an alternative to traditional therapy.

Formulation and evaluation of theophylline sustained release matrix tablets using synthetic polymers

The aim of present work was to develop theophylline sustained release tablets which could improve patient compliance towards the effective management of asthma The polymers, HPMC (Hydroxy propyl methyl cellulose) K4M, HPMC K100M, Eudragit, Chitosan in blending and granulation stage of processing and evaluate their physico-chemical properties. The precompression limits of the powder blends used for the preparation of sustained-release tablets were in an acceptable range of pharmacopeial specification with excellent flow and good compressibility. Wet granulation method prepared tablets using different grades of polymers HPMC K100, HPMC K4M, Eudragit, Chitosan. The active ingredient, release retardants, diluents, fraction of polymer are mixed to make wet mass for granulation. The in- vitro release was prolonged to 12 hours using HPMC K4M, HPMC K100M, Chitosan, Eudragit. F9 formulation prolonged the theophylline release in 12 hours. The effect of polymer on drug release was studied. Thus, sustained release matrix tablets can promise better patient compliance through reduction in over-all dose and dosage regimen, which can be of excessive support to treat chronic disease.

Formulation, Characterization and Release Behaviour of Metformin Hydrochloride Modified Release Tablet by Using Hydrophilic Polymers

Amongst the many public health problems, the diabetes mellitus is considered as a chronic life-style related disease which is now growing as an epidemic in both developed as well as developing countries. The current study is about formulation of metformin hydrochloride tablet to confirm their sustained release property by using various polymers. The tablets are prepared by granulation techniques using binding solution containing polyvinyl pyrolline K30. The possible interaction between the pure metformin hydrochloride and polymers are identified by Fourier transform-infrared spectroscopy. Tablets were formulated with different polymers like Hydroxy propyl methyl cellulose K100 and sodium carboxymethyl cellulose. Matrix prepared with high concentration of HPMC K100 polymer retards the drug release up to 6 h at 59 %, but the formulation 2 (F2) showed 72.72% of drug release in 6 h. The release of drug from the F2 formulation was found to be prolonged drug release when compared to other formulations. Hence our study conclude that the HPMC K100 polymer containing formulation showed good sustained release property owing to the high gel strength and well high viscosity nature of the polymer.

Exploration of in vitro drug release testing methods for saquinavir microenvironmental pH modifying buccal films

Buccal films containing a pH modifying excipient may be able to increase bioavailability of drugs with pH-dependent solubility such as saquinavir. Access to suitable in vitro drug release testing methods may facilitate buccal formulation development. This study aimed to explore two release testing methods for characterising buccal films and to elucidate the relationship between microenvironmental pH (pHM, i.e. the pH around the swelling films) and saquinavir release. The Franz diffusion cell method was applicable to investigate the effect of hydroxypropyl methylcellulose (HPMC) grade on saquinavir release. Films containing HPMC K3 LV had a faster saquinavir release than films containing HPMC K100 LV. A UV/Vis imaging method was developed to visualise saquinavir release and pHM changes during the initial dissolution. Within 5 min, the pHM decreased from 6.8 to around 5.4 for HPMC K100 LV-based films containing 11.1 % or 16.6 % (w/w) malic acid. Subsequently, the pHM increased due to increasing concentrations of saquinavir. An increase in malic acid content led to a faster saquinavir release. The combination of methods may be broadly applicable for excipient screening in development of buccal formulations. The imaging approach holds promise for characterizing other pH modifying formulation principles.

Quality by Design-driven investigation of the mechanical properties of mucoadhesive films for needleless anesthetics administration

Objectives: To systematically evaluate the effects of hydroxypropyl methyl cellulose (HPMC) type (E5LV, E15LV, and K100LV); plasticizer type (glycerol and mannitol), plasticizer loading (0.12 and 0.24% w/w); and loading of prilocaine and lidocaine hydrochlorides combined at 1:1 ratio (0 and 47 mg/cm2) in the mechanical properties of buccal films. Methods: A quality by design (QbD) approach based on a full factorial design (3 x 23) and complementarily multivariate statistical tools i.e., principal component analysis (PCA), response surface methodology (RSM), and correlation matrix were used in this pursuit. The thickness, elongation at break, tensile strength, force at break, and Young`s modulus of the anesthetic buccal films obtained by solvent casting were assessed. Results: The QbD, PCA and RSM altogether demonstrated that all studied formulation variables, mainly the drug loading, affect the mechanical properties of the films at different significance levels. The multivariate analysis yielded the modelling of elongation at break, tensile strength, and force at break, which significantly correlated with each other. The drugs exerted a synergic plasticizing effect on the films, and the use of HPMC K100 LV (with greater hydroxypropyl substitution degree and viscosity) and mannitol favored their elasticity and resistance. Furthermore, the majority of the films fulfilled the requirements for buccal administration due to their softness and mechanical resistance. Conclusion: Mannitol is suitable plasticizer for manufacturing HPMC anesthetic buccal films with improved mechanical properties. These results are a step forward in the rational development of formulations for the replacement of needles in dentistry

Investigation of Polymeric Micellar Nanoparticles of Amlodipine Besylatefor Transdermal Delivery

: Objectives: The objective of this study was to formulate and investigate amlodipine besylate loaded polymeric micelles and their effect on enhancing transdermal permeation of the poorly water-soluble drug via transdermal films. Methods: Pluronic F127 and Pluronic F68 polymers were chosen to prepare micelles in different drug – polymer ratios. Prepared formulations were characterised for surface morphology, micelle size, polydispersity index, zeta potential, loading efficiency, percentage drug weight in micelles and stability. Optimized amlodipine micelle dispersions were incorporated into hydroxypropyl methylcellulose K100 and polyvinyl pyrrolidone K30 transdermal films prepared by the solvent casting method. These films were evaluated for thickness, percentage weight variation, folding endurance, moisture absorbance, percentage drug content, ex vivo permeation and in vivo skin irritation. Results: Selected micelle formulations had the desired vesicle size, homogeneity and stability. Scanning electron microscopy show spherical vesicles. Micelle incorporated transdermal films were smooth, flexible, translucent and mechanically strong. The ex vivo skin permeation studies reveal that the flux of amlodipine besylate from the micelle incorporated transdermal films was significantly higher than that containing the free drug, confirming the drug solubilizing effects of micelles. Reconstitution of micelles from optimized films revealed that the original characteristics of the micelles were intact. Studies in Wistar rats showed that the prepared transdermal films were free of irritation potential when evaluated by the Draize dermal irritation scoring system. Conclusion: Beside their solubilizing effect, Pluronic micelles could be useful as novel drug carriers for enhancing transdermal permeation of Amlodipine besylate and thus its bioavailability.Key words: Hydroxypropyl methylcellulose, Micelle, Nanoparticle, Permeation, Pluronic, Skin irritation.

Development and Characterization of Controlled Release Tablets of Candesartan Cilexetil/ β‑Cyclodextrin Inclusion Complex

Objective: Matrix tablet approach is one of the delivery systems intended for poorly water-soluble drugs, like candesartan cilexetil (CC). CC is a class II drug used for the treatment of hypertension. Methods: Matrix tablets from (F1x to F18z) were prepared in the presence of β‑cyclodextrin. Matrix tablet formulation ensures control release of the drug and higher dissolution by β‑cyclodextrin. Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC) were used to study compatibility. Results: The angle of repose determination showed good flow for most of the formulas, besides having good compressibility. Weight variation test for all formulas showed accepted value. Drug content measurement showed accepted values. Friability and hardness of tablets were within the allowed values. Higher tablet swelling was obtained for the formulas containing hydroxypropyl methylcellulose (HPMC) K100M (F3x and F15z), in which the ratio of the polymer was 1:1 and 1:3, respectively. In vitro release showed that F1x to F13z were studied depends on the type and amount of polymer, i.e., 1:1, 1:2, and 1:3, respectively. F1x release after 8 hours was 95%, which contains 1:1 polymer ratio in comparison to F3x, which showed 85% after 8 hours, which includes 1:3 (drug: HPMC K100). Kinetic studies showed a zero-order model. Conclusion: The use of β‑cyclodextrin modifies the release profile of the drug, and some control the more sustained-release formulas. The lower the time of the release but in a range that a sustained release of the drug was observed in comparison with the formulas prepared without β‑cyclodextrin.

Piperine fast disintegrating tablets comprising sustained-release matrix pellets with enhanced bioavailability: formulation, in vitro and in vivo evaluation

Piperine (Pip) has been widely studied for its multiple activities such as antidepressant, anti-epileptic, and so forth. However, the poor water solubility coupled with low bioavailability may inevitably hinder the application of Pip in the clinical setting. In this study, a formulation strategy was proposed to spontaneously resolve the low bioavailability and dose dividing issue of Pip. The matrix pellets (Pip-SR-pellets) consisting of Pip solid dispersion (Pip-SD) and hydroxypropylmethyl cellulose-K100 were developed to achieve an increased and sustained release profile in vitro. The Pip-SR-pellets were compacted into fast disintegrating tablets (FDTs) with a blend of excipients comprising lactose, MCC, LS-HPC, and CMS-Na. The Pip-SD was characterized by solubility study and XRD. The evaluation of the cross-sectional morphology of the Pip-FDTs via scanning electron microscope proved that Pip-SR-pellets maintained its structural integrity during compression and were uniformly distributed in the Pip-FDTs. The release profile of Pip-SR-pellets was highly consistent with the Pip-FDTs. In vivo pharmacokinetics study demonstrated that the relative bioavailability of Pip-SR-pellets was approximately 2.70-fold higher than that of the pure drug, and 1.62-fold compared with that of Pip-SD. This work therefore showed a potential industrialized method could be applied to formulate poorly water-soluble drug that has dose-dividing requirement.

DEVELOPMENT AND CHARACTERIZATION OF CONTROLLED RELEASE TABLETS OF CANDESARTAN CILEXETIL/Β-CYCLODEXTRIN INCLUSION COMPLEX

Objective: Matrix tablet approach is one of the delivery systems intended for poorly water-soluble drugs like candesartan cilexetil. Candesartan cilexetil is a class II drug used for the treatment of hypertension.
 Methods: Matrix tablets from (F1x to F18z) were prepared in the presence of β-cyclodextrin. Matrix tablet formulation ensures control release of the drug and higher dissolution by β-cyclodextrin. Fourier transform infrared spectroscopy and differential scanning calorimetry were used to study compatibility.
 Results:The angle of repose determination showed good flow for most of the formulas besides having good compressibility. Weight variation test for all formulas showed accepted value. Drug content measurement showed accepted values. Friability and hardness of tablets were within the allowed values. Higher tablet swelling was obtained for the formulas containing hydroxy propyl methyl cellulose (HPMC) K100M (F3x and F15z) in which the ratio of the polymer was (1:1) and (1:3) respectively. In vitro release showed that F1x to F13z were studied depends on the type and amount of polymer i.e. (1:1), (1:2) and (1:3) respectively. F1x release after 8h was 95% which contain (1:1) polymer ratio in compare to F3x, which showed 85% after 8h, Which include 1:3 (drug: HPMC K100). Kinetic studies showed a zero-order model.
 Conclusion: The use of β-cyclodextrin modify the release profile of the drug, and control the sustained release formulas. The lower the time of the release but in a range that a sustained release of the drug was observed in compare with the formulas prepared without β-cyclodextrin.

Lysozyme Mucoadhesive Tablets Obtained by Freeze-Drying

Lysozyme is particularly attractive for the local treatment of oral pathologies related to microbiological infections. However, the requirement of a prolonged release is difficult to achieve because of saliva swallowing and of the protein denaturation which can occur during production and storage of a dosage form. This work demonstrates the feasibility to prepare lysozyme mucoadhesive tablets by freeze-drying. Tablets were prepared by using alginate (ALG) physically “cross-linked” with calcium ion and different grades of hydroxypropyl methylcellulose (HPMC) (i.e., E5, E50, or K100). The tablets were characterized in terms of swelling or erosion behavior, in vitro mucoadhesive properties, lysozyme activity (Micrococcus lysodeikticus), drug release and ability to inactivate Staphylococcus aureus. The formulations prepared with HPMC K100 were discarded because of the fast erosion. All other formulations allowed a sustained release over at least 6 h. Independently of composition, lysozyme activity (78,311 ± 1873 Units/mg) significantly decreased in the case of tablets containing 5% and 10% w/w of protein (55,000 Units/mg and 33,000 Units/mg, respectively). Conversely, no modifications occurred in the case of tablets containing 1% w/w lysozyme. The formulation prepared by ALG/HPMC E5 7/3 ratio was efficacious against S. aureus. After 3 months of storage at 5 ± 3°C, no significant decrease in lysozyme activity was observed.

ONCE DAILY IMMEDIATE-AND EXTENDED-RELEASE BILAYER TABLETS OF ETORICOXIB: A STUDY ON THE RELEASE KINETICS

Objective: In the present work, the main objective was to develop bilayer extended release matrix tablets of etoricoxib by providing a loading dose followed by maintenance dose that expected to improve the therapeutic efficacy of the medication with less toxic effect.
 Methods: Bilayer tablets of etoricoxib was developed successfully with the meticulous proportion of release controlling Hydroxy propyl methyl cellulose K100 (HPMC K100) and lactose. The tablets were prepared by wet granulation technique. Granules for immediate layer and extended layer for different formulations were prepared separately. The formulations were developed and evaluations were performed to examine the parameters that affect the in vitro performance of the tablets. The drug-excipient compatibility was ensured by Fourier transform infrared spectroscopy (FTIR) study.
 Results: The values of physical parameters of all formulations were found within appreciable limit. Formulation containing HPMC K 100 and lactose in the proportion of 2:1 in the extended release layer was able to release 26.22% of drug in 15 min and shown a steady release of drug for an extended period of 12 h. The dissolution data was put in Korsemeyer–Peppas model in order to find out n value, which describes the drug release mechanism. The n-value of different formulations were found to be variable. The Fourier transform infrared spectroscopy (FTIR) study revealed absence of any other new peaks and also no differences in the positions of the absorption bands in the bilayer tablet F8 that indicate the lack of significant interactions between etoricoxib and other excipients.
 Conclusion: It had been concluded that once daily immediate-and extended release bilayer tablet of etoricoxib can be formulated with profound physical characteristics and dissolution properties. This resulted in reducing the daily dose and thus minimise the cardiovascular toxicity of etoricoxib.

Investigation into the Solid-State Properties and Dissolution Profile of Spray-Dried Ternary Amorphous Solid Dispersions: A Rational Step toward the Design and Development of a Multicomponent Amorphous System.

The formulation of oral amorphous solid dispersions (ASD) includes the use of excipients to improve physical stability and enhance bioavailability. Combinations of excipients (polymers and surfactants) are often employed in pharmaceutical products to improve the delivery of poorly water-soluble drugs. However, additive interactions in multicomponent ASD systems have not been extensively studied and may promote crystallization in an unpredictable manner, which in turn may affect the physical stability and dissolution profile of the product. The main aim of this study was to understand the effect of different surfactant and polymer combinations on the solid-state properties and dissolution behavior of ternary spray-dried solid dispersions of dipyridamole and cinnarizine. The surfactants chosen for this study were sodium dodecyl sulfate and poloxamer 188, and the model polymers used were polyvinylpyrrolidone K30 and hydroxypropyl methylcellulose K100. The spray-dried ternary dispersions maintained higher supersaturation compared to either the crystalline drug equilibrium solubility or their respective physical mixtures. However, rapid and variable dissolution behavior was observed for different formulations. The maximum supersaturation level was observed with drug-polymer-polymer ternary dispersions. On the other hand, incorporating the surfactant into binary (drug-polymer) and ternary (drug-polymer-polymer) ASDs adversely affected the physical stability and dissolution by promoting crystallization. On the basis of these observations, a thorough investigation into the impact of combinations of additives on amorphous drug crystallization during dissolution and stability studies is recommended in order to develop optimized formulations of supersaturating dosage forms.

FORMULATION AND CHARACTERIZATION OF SUSTAINED RELEASE COATED MATRIX GRANULES OF METFORMIN HYDROCHLORIDE

Objective: Metformin hydrochloride is a biguanide antihyperglycemic agent which is a generally recommended first-line drug for the treatment of diabetes mellitus (Type II). The purpose of this investigation is to prepare sustained release matrix granules of metformin hydrochloride which are coated to extend the drug release over a longer time period.Methods: Metformin hydrochloride granules were prepared by mixing all the dry powders in a V-cone blender and wetting the powder mix with aqueous solution of hydroxypropyl methyl cellulose K100. The prepared granules (MG1-MG5) were investigated for drug release. The batch of granules which exhibited extended release for up to 4 h was coated in a standard coating pan with blends of Eudragit RS and RL to further enhance release period. These were marked as coated metformin granules (CMG3) and CMG4 which were later filled into empty capsules. The granules were characterized for micromeritic properties, percentage yield, particle size distribution, percentage of drug content, and in vitro release of the drug.Results: All the formulations showed percentage yield in the range of 77.66–82.86% and drug content in the range of 78.23–96.62%. CMG3 showed drug release of 97.02% for 12 h. Fourier-transform infrared spectroscopy and differential scanning calorimetry studies indicated that no possible interaction existed between the drug and the polymers used. Scanning electron microscopy images revealed that the granules were spherical in shape with smooth surface and completely covered with a coating of polymer. Kinetic analysis of drug release confirmed that drug release followed zero-order kinetics where it is independent of the concentration.Conclusion: From the results, it was analyzed that design of coated granules employing the polymers used in the present work can produce a sustained release of the drug over a period of 12 h.

DESIGN AND COMPARATIVE EVALUATION OF CLARITHROMYCIN GASTRIC BIOADHESIVE TABLETS BY EX VIVO AND IN VIVO METHODS

Objective: The present investigation was to formulate controlled release of mucoadhesive clarithromycin tablets using natural polymers.Methods: Tamarind seed polysaccharide obtained from Tamarindus indica and chitosan act as natural polymers. The formulated tablets of the combined form of thrombospondin (TSP) and chitosan were analyzed by in vitro dissolution method. The optimized formulations were selected for ex vivo and in vivo studies and compared with hydroxypropyl methylcellulose K100 polymer by evaluating gastric retention period by X-ray imaging technique, and drug bioavailability by a pharmacokinetic method from blood samples was determined by high-performance liquid chromatography-mass spectrometry method.Results: The gastric mucoadhesive tablets were prepared using chito-TSP polymers. The in vitro drug release showed good release character for 24 h. The ex vivo studies of tablets showed good adhesive property for a long time. The X-ray imaging technique also proved the adhesive character of tablets. From blood serum sample of rabbits, bioavailability of the drug is in according to the controlled release mechanism.Conclusion: The selected formulations were subjected to stability studies. The study concluded that combination of chitosan and TSP is best natural polymer for mucoadhesion by the advantages of controlled release and biodegradation.

FORMULATION AND EVALUATION OF NOVEL CHROMENE DERIVATIVE AS AN ANTI INFLAMMATORY AGENT USED FOR IBD

Objective: To formulate and evaluate an extended-release (ER) tablet of a new molecule, 2-amino-4-(4-bromophenyl)-7-hydroxy-4H-chromene-3- carbonitrile using a combination of two polymers (hydroxypropyl methyl cellulose [HPMC] K100 and HPMC phthalate) which control the rate and degree of the drug release through 12 hrs period and protect the drug release from acidic pH.Methods: Five batches of tablets (4HC1, 4HC2, 4HC3, 4HC4, 4HC5) were produced by direct compression method. Morphological evaluation of the powder blend was carried out by differential scanning calorimetry and Powered X-ray diffractometry. The evaluation studies such as flow properties, hardness, friability, drug content, and release study were conducted according to pharmacopoeial standards.Results: The physicochemical characteristics of all the granules and tablets were generally satisfactory. The drug release followed zero order, Higuchi model kinetics with diffusion and dissolution mediated mechanism. Tablets were evaluated for physicochemical parameters and promising. Stability studies indicated the dosage form is stable for 3 months at accelerated conditions.Conclusion: From the results received from all test, it was concluded that formulation 4HC4 are the most suitable choice for developing 12 hrs ERtablets. This finding reveals that a particular concentration of HPMC K100 was capable of producing ER.Keywords: Chromene derivative, Extended-release, Hydroxypropyl methylcellulose phthalate, Hydroxypropyl methylcellulose K100.

Development and Optimization of Controlled Porosity Osmotic Tablets of Lamotrigine Solid Dispersion.

The purpose of this study was to investigate the application of a controlled porosity osmotic tablet (CPOT) utilizing solid dispersion (SD) of poorly soluble drug. The patents on Cyclobenzaprine HCl (US4968507 A) and Venlafaxine salts (EP 2085078 A1) helped in the selection of drug and polymers. The SDs having different ratio of drug to carrier (PVP K 30) were prepared by kneading method and optimized. Effect of three independent variables, total amount of osmogen (mannitol& potassium chloride), total amount of polymer (polyethylene oxide WSR 301, hydroxy propyl methyl cellulose K100 M) and polymer1: polymer 2 ratio were investigated using Box Behnken design. Core and coated tablets were evaluated for various parameters. In-vitro drug release profiles of CPOT tablets were compared with reference product Diffcore tablet, Lamictal XR (GlaxoSmith Kline Inc., USA). All formulations showed acceptable parameters. Drug release from CPOT was determined as complete, zero order and pH-independent within the physiological pH range of the GI tract. Drug release was directly proportional to initial level of polymers and osmogens. The present results confirmed that prepared LTG SD serves as solubility modulator. Further, CPOT of LTG based on SD proved to be successful in delivering the drug in a controlled manner ensuring the once daily dosing for the treatment of convulsive disorders.

Formulation and Evaluation of Gastro-bilayer Floating Tablets of Simvastatin as Immediate Release Layer and Atenolol as Sustained Release Layer

Combination therapy is highly desired to deliver atenolol and simvastatin for dyslipidemia and hypertension for concomitant drug treatment. On other hand, atenolol has poor absorption in lower gastrointestinal tract, short half-life and simvastatin has poor solubility. Therefore, the present study was to develop gastro-bilayer floating matrix tablet in which simvastatin was incorporated as immediate layer and atenolol as sustained release layer. Gastro-bilayer floating tablets were prepared by direct compression method and optimized using hydroxypropyl methylcellulose K100 (37.5%) as release retardant and sodium bicarbonate as a gasforming agent. The immediate release layer comprised sodium starch glycolate as superdisintegrant. The tablets of optimized formulations floated on the test medium for more than 12 h with 9 min of floating lag time. Atenolol release was sustained for 12 h via diffusion mechanism and more than 96% release of simvastatin within 15 min was achieved. It can be concluded that, the biphasic drug release pattern was successfully achieved through the formulation of gastro-floating bilayer tablets in this study, allowing strengthened combination therapy for hypertension and dyslipidemia.

Formulation and Evaluation of Buccoadhesive Tablets of Losartan Potassium

The present investigation is concerned with formulation and evaluation of buccoadhesive tablets containing antihypertensive drug, Losartan Potassium to avoid the first pass effect and to improve its bioavailability with reduction in dosing frequency and dose related side effects. The tablets were prepared by wet granulation method. Nine formulations were developed with varying concentrations of polymers like hydroxypropylmethyl cellulose K100 and Guar gum. The tablets were tested for hardness, friability, weight variation, content uniformity, surface pH, swelling index, ex vivo mucoadhesive strength, in vitro drug dissolution study and ex-vivo permeation study. FTIR and DSC studies showed no evidence on interactions between drug and excipients. The in vitro release of Losartan Potassium was performed under sink conditions. The mucoadhesive strength of formulation F9 was found to be 0.14307 N. The swelling index of formulation F9 was found to be 87%. The formulation F9, containing 25 mg of losartan potassium exhibited 6 h sustained drug release of 96% with desired therapeutic concentration. The in vitro release kinetics studies revealed that all formulations fits well with zero order kinetics followed by Korsemeyer-Peppas model and the mechanism of drug release is Non-Fickian diffusion. Based on the results of ex vivo mucoadhesive strength and swelling index studies formulation F9 was selected as optimized formulation and subjected for stability study. Short-term stability studies on the promising formulation indicated that there are no significant changes in drug content and in vitro dissolution characteristics.

Obtainment of pellets using the standardized liquid extract of Brosimum gaudichaudii Trécul (Moraceae).

Background:The standardized liquid extract of Brosimum gaudichaudii Trécul is an alternative for the treatment of vitiligo. There is a shortage of solid oral dosage forms developed from standardized extracts of this plant specie.Objective:This study is aimed to obtain pellets with a standardized liquid extract of B. gaudichaudii.Results:The standardized liquid extract of B. gaudichaudii was obtained through maceration and percolation with a 55% ethanol-water solution (v/v). Pellets were obtained through a mixture of extract of 500 g of B. gaudichaudii standardized extract, 500 g of microcrystalline cellulose PH101 and 10 g of hydroxypropyl methylcellulose K100. The pellets obtained presented a homogeneity yield of 92%, aspect ratio of 1.16 ± 0.65, shape fator eR of 0.35 ± 0.09 and Feret diammeter of 0.87 ± 0.27. These pellets were coated with a suspension composed of titanium dioxide, aluminum red lacquer, ethyl cellulose, talc and magnesium stearate. Before the photostability test, the uncoated pellets showed psoralen content equal to 0.13 ± 0.01% and to the 5-MOP was 1.40 ± 0.27%. After exposure to one level (3 J.cm-2) of UVB irradiation the uncoated pellets presented a degradation of 2.16% of psoralen and 8.1% of 5-MOP. After exposure to three levels (10, 20 and 30 J.cm-2) of UVA irradiation the uncoated pellets exhibited photodegradation of 9.78, 17.64, 24.21% of psoralen and 18.95, 23.68, 28.48% for 5-MOP. The coated pellets where unaffected after photostability test.Conclusion:Pellets were obtained with the standardized liquid extract of B. gaudichaudii and coating is a technological alternative to ensure the stability of the formula.

Development and Evaluation of Gastroretentive Atenolol Tablets

The low oral bioavailability of atenolol is primarily because of its poor absorption from the lower gastrointestinal tract. Gastroretentive dosage forms provide an opportunity to deliver the drug with absorption window in the proximal part of the GIT thereby increasing their bioavailability. The objective of this study was to develop a dosage form for atenolol with the objective of increasing the gastric residence and there by its oral bioavailability. Different formulations of floating tablets of atenolol (AT1-AT10) were prepared by varying the composition of hydroxypropyl methyl cellulose (HPMC) K100, lactose and citric acid. The tablets were evaluated for various parameters like friability, weight variation, content variation, floating lag time, total buoyancy and in vitro dissolution. The physicochemical properties of the prepared formulations were found to possess adequate physical integrity. Formulation AT8 showed the lowest floating lag time with 14 h buoyancy. Drug release was found to be dependent on the concentration of HPMC K100 and lactose in the formulation. Further, the increase in amount of citric acid leads to increase in atenolol release rate while reduces the floating time. The findings revealed that the formulation AT8 retarded the atenolol release (~73% in 12 h) and followed zero order kinetics. The in vitro data observed here substantiate the potential of the prepared formulation to provide adequate drug release and buoyancy to improve the bioavailability of atenolol, which necessitate further in vivo studies.