Formulation, Development And In Vitro Evaluation Of Tramadol Extended Release Tablets

Objective: The objective of the present study was to develop “once daily” extended release tablets of tramadol (100 mg) by wet granulation using hydrophilic polymer like hydroxy propyl methyl cellulose K100M,K15M and polyethylene oxide (PEO). Methods: The tramadol matrix tablets were prepared by using different polymers like hydroxy propyl methyl cellulose (HPMC K15M and K100M), polyethylene oxide (PEO) as the nontoxic and easily available suitable matrix system. The extended release tablets of tramadol (400 mg) were prepared wet granulation technique. Different pre compression and post compression were performed. In vitro dissolution tests were performed and percentage drug release was calculated. The fourier-transform infrared spectroscopy (FTIR) studies conducted on pure drug tramadol and the optimize formulation (T6). Different release models like zero order, first order, higuchi and Korsemeyer-Peppas were applied to in vitro drug release data in order to evaluate the drug release mechanisms and kinetics. Results: Pre compression and post compression parameters satisfied with pharmacopeia specifications. The In vitro release studies were performed using USP type II apparatus showed that optimized formulation T6 consisting of polyethylene oxide (PEO) with 25 mg of the polymer was found to extended release of tramadol over a period of 24h. The optimized formulation T6 followed the zero order kinetics as correlation coefficient (r2) values are higher than that of first-order release kinetics. In order to understand the complex mechanism of drug release from the optimized formulation T6 matrix system, the in vitro release rate were fitted to Korsemeyer-Peppas model and the release exponent value (n) obtained was 0.82105 exhibited anomalous (non fickian) diffusion mechanism. Conclusion: The present study shows that polyethylene oxide was found to play a great role in controlling release of tramadol from the matrix system. Accordingly it can be concluded that the formulation is robust in the performance is less likely to be affected by the various factors studied.

Key Formulation Considerations of Push-Pull Osmotic Pump (PPOP) Drug Delivery System / 中国药学杂志

OBJECTIVE: Push-pull osmotic pump (PPOP) is one of conventional osmotic pump systems, which has been widely investigated for formulation development of BCS Ⅱ APIs. However, there is still a lack of experimental data based discussions for some key formulation factors of PPOP. Thus, to investigate some key formulation factors by designed experiments and tried to give some recommendations for those considerations in industrial formulation development. METHODS: Nifedipine was selected as the model drug in this study. The hydration & swell rate and strength of three grades of commercialized high molecular weight polyethylene oxide (PEO) were evaluated via swelling volume change using a home-made apparatus and via compression force using texture analyzer, respectively. The effect of different film coating thickness, proportion of osmotic agent in push layer, and ratios of push layer to pull layer were investigated by drug dissolution using USP apparatus Ⅱ as well. RESULTS: The swelling rate and strength of three grades of high molecular weight PEO (POLYOXTM 301, POLYOXTM Coagulant, and POLYOXTM 303) enhanced along with the molecular weight. The difference of swelling rate is not significant (P>0.05), but that of swelling gel strength is significant (P<0.05). Adding osmotic agent, e.g. NaCl, could significantly improve the swelling rate. Thicker coating membrane retarded drug release and as the coating thickness was higher than 180 μm, it caused incomplete drug release (<90%). When the NaCl proportion in push layer was between 10% and 30 %, there was no significant differences among drug dissolution profiles. However, when the percent of NaCl content in push layer was above 50%, the drug release from PPOP became slower and more incomplete (<90%). CONCLUSION: The ratio of DL/PL has significant impact on drug release. The lower the ratio of DL/PL resulted in faster and more complete drug release. For nifedipine case, the ratio of 2 was recommended.

A Five-Year Stability Study of Controlled-Release Diltiazem Hydrochloride Tablets Based on Poly(Ethylene Oxide).

The aim of this study is to investigative the stability of poly(ethylene oxide) (PEO) matrix tablets containing diltiazem hydrochloride (DTZ) after five-year storage at room temperature. DTZ matrix tablets containing different molecular weights (MW) of PEO and electrolytes (sodium carbonate anhydrous Na2CO3, potassium chloride KCl and pentasodium tripolyphosphate anhydrous PSTPP) were prepared. The fresh and stored tablets were evaluated by DTZ content, in vitro drug release rates and kinetics as well as DSC. All the PEO’s matrix tablets showed no significant changes in release rate, kinetics and drug content. The release rates of DTZ following five-year storage were slightly increased as the MW of PEO increased from 900,000 to 8,000,000. Also, it was clear that the addition of electrolyte drastically slowed the release rates of DTZ from fresh and stored tablets. DSC thermograms and similarity factor (ƒ2) depicted good system stability for all stored tablets. This is the first five-year long-term stability study reported concerning DTZ/PEO matrix tablets with different MW, which proved its stability for several years. This study might throw light on the dramatic difference observed between this study and the reported data of accelerated stability testing under stress conditions found in the literature.

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

The aim of the present research is to formulate and evaluate the gastroretentive floating drug delivery system of antihypertensive drug, propranolol HCl. Gastroretentive floating tablets (GRFT) were prepared by using a synthetic hydrophilic polymer polyethylene oxide of different grades such as PEO WSR N-12 K and PEO 18 NF as release retarding polymers and calcium carbonate as gas generating agent. The GRFT were compressed by direct compression strategy and the tablets were evaluated for physico-chemical properties, in vitro buoyancy, swelling studies, in vitro dissolution studies and release mechanism studies. From the dissolution and buoyancy studies, F 9 was selected as an optimized formulation. The optimized formulation followed zero order rate kinetics with non-Fickian diffusion mechanism. The optimized formulation was characterised with FTIR studies and observed no interaction between the drug and the polymers.

O objetivo da presente pesquisa é o de formular e avaliar o sistema de liberação de fármaco gastrorretentivo flutuante, contendo o anti-hipertensivo, cloridrato de propranolol. Comprimidos gastrorretentivo flutuantes (GRFT) foram preparados utilizando um polímero hidrofílico sintético, o óxido de polietileno, de diferentes graus, tais como GE WSR N-12 K e GE 18 NF, como polímeros de retardamento de liberação, e carbonato de cálcio, como agente gerador de gases. Os GRFT foram comprimidos por compressão direta e avaliados para determinação das propriedades físico-químicas, flutuabilidade in vitro, estudos de inchamento, de dissolução in vitro e de mecanismo de liberação. Dos testes de dissolução e de flutuabilidade, selecionou-se F 9 como formulação otimizada. A formulação otimizada seguiu cinética de ordem zero, com mecanismo de difusão não-Fickiano. Essa formulação foi caracterizada por estudos de FTIR, não se observando interação entre o fármaco e os polímeros.

Design and evaluation of a gastroretentive drug delivery system for metformin HCl using synthetic and semi-synthetic polymers / Diseño y evaluación de un sistema gastro-retentivo de administración de metformina HCl, utilizando polímeros sintéticos y semisintéticos

The aim of the present research was to prepare and evaluate a gastroretentive drug delivery system for metformin HCl, using synthetic and semi-synthetic polymers. The floating approach was applied for preparing gastroretentive tablets (GRT) and these tablets were manufactured by the direct compression method. The drug delivery system comprises of synthetic and semi-synthetic polymers such as polyethylene oxide and Carboxymethyl ethyl cellulose (CMEC) as release-retarding polymers. GRT were evaluated for physico-chemical properties like weight variation, hardness, assay friability, in vitro floating behaviour, swelling studies, in vitro dissolution studies and rate order kinetics. Based upon the drug release and floating properties, two formulations (MP04 & MC03) were selected as optimized formulations. The optimized formulations MP04 and MC03 followed zero order rate kinetics, with non-Fickian diffusion and first order rate kinetics with erosion mechanism, respectively. The optimized formulation was characterised with FTIR studies and it was observed that there was no interaction between the drug and polymers.

El objetivo del presente trabajo consistió en preparar y evaluar un sistema de administración gastro-retentivo de metformina HCl, utilizando polímeros sintéticos y semisintéticos. Se aplicó el método de flotación para la elaboración de los comprimidos de retención gástrica (CRG) y éstos se prepararon mediante el método de compresión directa. El sistema de suministro del fármaco estaba constituido por polímeros sintéticos y semisintéticos, tales como el óxido de polietileno y la carboximetil etil celulosa, como agentes retardadores de la liberación del fármaco. Se evaluaron las propiedades físico-químicas de los CRG, tales como: variación de peso, dureza, friabilidad, comportamiento flotante in vitro, capacidad de inflación, estudios de disolución in vitro y su tasa de orden cinético. Se seleccionaron dos fórmulas (MP04 y MC03), sobre la base de la liberación del fármaco y las propiedades de flotabilidad, como fórmulas óptimas. Estas fórmulas MP04 y MC03 optimizadas siguieron cinéticas de velocidad de orden cero, con difusión no-Fickian y tasa cinética de primer orden con mecanismo de erosión, respectivamente. Las fórmulas óptimas se caracterizaron con estudios FTIR y se observó que no hubo interacción entre el fármaco y los polímeros.

A Novel Directly Compressible Co-Processed Excipient for Sustained Release Formulation.

A novel directly compressible (DC) co-processed excipient with improved functionality and masking the undesirable properties of individual excipients was developed without any chemical modification by using simple laboratory technique. For the development of co-processed excipient, release retarding polymers such as Polyethylene oxide (Polyox® WSR 301) and hydroxyl propyl methyl cellulose (Methocel® K4M) were used. Co-processed excipient was prepared in polymers weight ratio of 1:9 to 9:1 by roller compaction technique. Co-processed excipient prepared from polymers ratio of 7:3 and 8:2 showed good physico-chemical properties. The developed DC grade co-processed excipient was characterized for DSC, FTIR, SEM, XRD which confirms the absence of any chemical changes during co-processing. Highly water soluble Metoprolol succinate and poorly water soluble anhydrous Theophylline was used as model drugs for Invitro release study. Formulations prepared using co-processed excipient showed sustain drug release in which initial burst release was controlled by polyethylene oxide and HPMC controls the extended drug release. Developed formulations were kept for stability study for three month as per ICH guidelines and found to be stable. Study indicates that use co-processed excipient has added advantage over polymer with single property and can be used in sustain release formulation irrespective of drug type.

Development of enteric coated sustained release minitablets containing mesalamine

The aim of this study was to develop and evaluate a multiparticulate modified release system, composed of minitablets with a sustained release matrix system coated with a pH-dependent release polymer, using mesalamine as a model drug. Polyox® WSR 1105 was the polymer used in the matrix system and Eudragit® L30D55 was used as a pH-dependent polymer. The minitablets (with 20%, 30% or 40% Polyox® concentration) were prepared by dry granulation, which led to good quality minitablets. The developed minitablets were coated in a fluidized bed at 8% of the coating level. Dissolution studies were performed in media that simulated the gastrointestinal tract (pH 1.4, 6.0 and 7.2) and showed that formulations with higher Polyox® concentrations were capable of retaining the drug release in pH 1.4. All formulations prolonged the drug release and presented zero-order kinetic behaviour. The Korsmeyer-Peppas model demonstrated that formulations with 20% or 30% of polymer exhibited anomalous transport behaviour, whilst the 40% sample exhibited super case II model transportation. Dissolution efficiency showed that only the formulations containing 20% and 40% polymer could be considered statistically different.

O presente trabalho teve como objetivo desenvolver e avaliar um sistema multiparticulado de liberação modificada, composto por minicomprimidos com sistema matricial de liberação prolongada revestidos com polímero de liberação pH-dependente, utilizando mesalazina como fármaco modelo. Polyox® WSR 1105 foi o polímero utilizado no sistema matricial e Eudragit® L30D55 foi utilizado como polímero pH-dependente. Os minicomprimidos (com 20%, 30% e 40% de concentração de Polyox®) foram preparados por granulação via seca, gerando minicomprimidos de boa qualidade. Os minicomprimidos desenvolvidos foram revestidos em leito fluidizado a 8% de nível de revestimento. Efetuou-se o estudo de dissolução em meios que simulam o trato gastrointestinal (pH 1,4, 6,0 e 7,2) e as formulação contendo maiores concentrações de Polyox® foram capazes de reter a liberação do fármaco em pH 1,4. Todas as três formulações apresentaram liberação prolongada e comportamento cinético de ordem zero. O modelo de liberação de Korsmeyer-Peppas mostrou que as formulações com 20% e 30% de polímero apresentam comportamento de transporte anômalo, enquanto a com 40%, transporte super caso II. A eficiência de dissolução mostrou que somente as formulações com 20% e 40% de concentração do polímero foram consideradas estatisticamente diferentes.

Studies on sustained release solid dispersion of tanshione composition / 中草药

Objective: To prepare the sustained release solid dispersions of tanshinone composition with the intention of improving drug dissolution and controlling drug release. Methods: The glycerin monostearate (GMS) and polyethylene oxide (PEO) were used as composite carriers to prepare tanshinone solid dispersions by solvent melting method and the in vitro dissolution of tanshinone solid dispersions was performed. The structure of solid dispersions was characterized by SEM, DSC, XRD, and FTIR. Results: When the ratio of drug to composite carriers (GMS-PEO 2:1) was 1:8, the solid dispersions had a better sustained release effect, the accumulative drug-release percent in vitro at 12 h was over 90%, and the results from the phase analysis indicated that the tanshinone composition existed in carriers as amorphous state. Conclusion: The in vitro dissolution of tanshinone is greatly improved by the solid dispersions with GMS-PEO as its carriers. And it exhibits excellent release characteristics in vitro with the actual applied value.

Thermal sintering: a novel technique in the design of gastroretentive floating tablets of propranolol HCl and its evaluation / Sinterización térmica: Una técnica novedosa en el diseño de tabletas flotantes gastroretentivas de HCl propanolol y su evaluación

The aim of the present investigation was to formulate thermally sintered floating tablets of propranolol HCl, and to study the effect of sintering conditions on drug release, as well as their in vitro buoyancy properties. A hydrophilic polymer, polyethylene oxide, was selected as a sintered polymer to retard the drug release. The formulations were prepared by a direct compression method and were evaluated by in vitro dissolution studies. The results showed that sintering temperature and time of exposure greatly influenced the buoyancy, as well as the dissolution properties. As the sintering temperature and time of exposure increased, floating lag time was found to be decreased, total floating time was increased and drug release was retarded. An optimized sintered formulation (sintering temperature 50°C and time of exposure 4 h) was selected, based on their drug retarding properties. The optimized formulation was characterized with FTIR and DSC studies and no interaction was found between the drug and the polymer used.

El propósito de la presente investigación fue la elaboración de tabletas flotantes de HCL propanolol térmicamente sinterizadas y estudiar los efectos de las condiciones de sinterización sobre la liberación de la droga, así como sobre sus propiedades de flotabilidad in vitro. Se seleccionó un polímero hidrofílico, el óxido de polietileno, como polímero sinterizado, para retardar la liberación de la droga. Las fórmulas se prepararon mediante un método de compresión directa y se evaluaron mediante estudios de disolución in vitro. Los resultados demostraron que la temperatura de sinterización y el tiempo de exposición tuvieron una gran influencia sobre las propiedades de flotabilidad y de disolución. Se encontró que el intervalo de retardo en la flotación disminuyó, el tiempo total de flotación aumentó y se retardó la liberación de la droga, a medida que aumentaron la temperatura de sinterización y el tiempo de exposición. Se seleccionó una fórmula óptima de sinterización (temperatura de sinterización de 50°C y tiempo de exposición de 4 h), basados en las propiedades retardativas sobre la droga. La fórmula sinterizada se caracterizó mediante estudios FITR y DSC y no se encontró ninguna interacción entre la droga y el polímero utilizado.

Design and in vitro evaluation of effervescent gastric floating drug delivery systems of propanolol HCl / Diseño y evaluación in vitro de sistemas de administración de tabletas flotantes gástricas everfescentes de HCl propanolol

The purpose of this research was to develop and evaluate effervescent gastric floating tablets of propranolol HCl. The oral delivery of antihypertensive propranolol HCl was facilitated by preparing an effervescent floating dosage form which could increase its absorption in the stomach by increasing the drug’s gastric residence time. In the present work, effervescent floating tablets were prepared with a hydrophilic carrier such as polyethylene oxide (PEO WSR N 60K and PEO WSR 303) as a release retarding agent and sodium bicarbonate as a gas generating agent. The prepared tablets were evaluated for all their physicochemical properties, in vitro buoyancy, drug release and rate order kinetics. From the results, P9 was selected as an optimized formulation based on their 12 h drug release, minimal floating lag time and maximum total floating time. The optimized formulation followed first order rate kinetics with erosion mechanism. The optimized formulation was characterized with FTIR studies and no interaction between the drug and the polymers were observed.

El propósito de la presente investigación fue desarrollar y evaluar tabletas flotantes, efervescentes de HCL propranolol. La administración oral del antihipertensivo HCL propranolol se facilitó mediante la preparación de una forma de dosificación flotante y efervescente que permitiría su absorción en el estómago, mediante el aumento del tiempo de residencia gástrico de la droga. En el presente trabajo, las tabletas flotantes efervescentes fueron preparadas con un portador hidrofílico, tal como el óxido de polietileno (PEO WSR N 60K and PEO WSR 303), como agente retardador y bicarbonato de sodio como un agente generador de gas. Se evaluaron todas las propiedades fisicoquímicas de las tabletas preparadas, su flotación in vitro y su tasa de orden cinético. Se seleccionó el P9 a partir de los resultados obtenidos, como una fórmula óptima, basados en la liberación de la droga a las 12 h, tiempo mínimo de retraso para flotación y máximo tiempo total de flotación. La formulación optimizada siguió una tasa cinética de primer orden con mecanismo de erosión. Esta fórmula óptima se caracterizó mediante estudios FITR y no se observó ninguna interacción entre la droga y los polímeros utilizados.

Formulation and characterization of gastroretentive discs containing famotidine

In this work a different type of formulation, as disc, containing a selected mucoadhesive polymer, fillers, and binders were investigated for their potential as a mucoadhesive gastroretentive delivery system to deliver famotidine in the stomach. Various types of hydrophilic diluents were evaluated for their swelling and mucoadhesive property and one (polyvinylpyrrolidone, PVP) was selected to combine with the selected mucoadhesive polymer (polyethylene oxide, PEO). Discs with different ratios of PEO and PVP were prepared and evaluated for swelling, dissolution, and mucoadhesion. The swelling property of the discs increased as the concentration of PEO was increased and also did the mucoadhesion. These discs retained their integrity and adherence onto gastric mucosa for more than 10 h under in-vitro conditions. The PEO, in combination with PVP, yielded a non-disintegrating type mucoadhesive dosage form which was suitable for gastroretentive applications to achieve the desired release profile of the drug.