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Evaluation of coprocessed disintegrants produced from tapioca starch and mannitol in orally disintegrating paracetamol tablet.  


The study evaluated two novel coprocessed excipients (with two methods) as disintegrants in an orally disintegrating paracetamol tablet formulation. The tablets produced were assessed for mechanical properties with the use of friability and tensile strength while the release properties were assessed with wetting time, water absorption ratio, disintegration time and dissolution profile. The results obtained showed that the methods of coprocessing and disintegrant incorporation influenced the activities of the disintegrants. The novel disintegrant enhanced the mechanical properties of the tablets containing them as shown by lower friability and higher tensile strength of the tablets. The result further showed that the rate and amount of water absorbed, type of disintegrant and the method of disintegrant incorporation influenced the total amount of paracetamol released. The study concluded that the novel disintegrants will be effective in the formulation of orally disintegrating paracetamol tablets. PMID:25362809

Adeoye, Oluwatomide; Alebiowu, Gbenga



Functionality of disintegrants and their mixtures in enabling fast disintegration of tablets by a quality by design approach.  


Investigation of the effect of disintegrants on the disintegration time and hardness of rapidly disintegrating tablets (RDTs) was carried out using a quality by design (QbD) paradigm. Ascorbic acid, aspirin, and ibuprofen, which have different water solubilities, were chosen as the drug models. Disintegration time and hardness of RDTs were determined and modeled by executing combined optimal design. The generated models were validated and used for further analysis. Sodium starch glycolate, croscarmellose sodium, and crospovidone were found to lengthen disintegration time when utilized at high concentrations. Sodium starch glycolate and crospovidone worked synergistically in aspirin RDTs to decrease disintegration time. Sodium starch glycolate-crospovidone mixtures, as well as croscarmellose sodium-crospovidone mixtures, also decreased disintegration time in ibuprofen RDTs at high compression pressures as compared to the disintegrants used alone. The use of sodium starch glycolate in RDTs with highly water soluble active ingredients like ascorbic acid slowed disintegration, while microcrystalline cellulose and crospovidone drew water into the tablet rapidly and quickened disintegration. Graphical optimization analysis demonstrated that the RDTs with desired disintegration times and hardness can be formulated with a larger area of design space by combining disintegrants at difference compression pressures. QbD was an efficient and effective paradigm in understanding formulation and process parameters and building quality in to RDT formulated systems. PMID:24848762

Desai, Parind Mahendrakumar; Er, Patrick Xuan Hua; Liew, Celine Valeria; Heng, Paul Wan Sia



Clinical disintegration time of orally disintegrating tablets clinically available in Japan in healthy volunteers.  


Disintegration time is an important characteristic of orally disintegrating tablets (ODTs), and evaluation of disintegration time is a key step in formulation development, manufacturing, and clinical practice. In this study, we aimed to clarify the clinical disintegration time of ODTs that are currently used clinically, and to evaluate its correlation with the in vitro disintegration time of ODTs which was measured using Tricorptester, a newly developed disintegration testing apparatus. The clinical disintegration time of 17 ODT products was measured in healthy volunteers (n=9-10; age range, 21-28 years). A randomized single-blind trial was performed; each tablet was placed on the tongues of the participants, and it disintegrated in their oral cavities. No significant difference was observed in the clinical disintegration time of each ODT among the 3 groups to which the subjects were randomly assigned. The clinical disintegration time of the 17 ODT products was between 17.6 s and 33.8 s. The in vitro disintegration time of 26 clinically used ODT products measured using Tricorptester ranged between 4.40 s and 30.4 s. A significant positive correlation was observed between in vitro and clinical disintegration times (r=0.79; p<0.001). This study shows that all the tested products, which are clinically available in Japan, showed good disintegration and that the disintegration time varied according to the product. In addition, the in vitro disintegration time of ODTs measured using Tricorptester is a good reflection of the disintegration time in the oral cavity. PMID:23995661

Yoshita, Tomohiro; Uchida, Shinya; Namiki, Noriyuki



Prediction of oral disintegration time of fast disintegrating tablets using texture analyzer and computational optimization.  


One of the promising approaches to predict in vivo disintegration time of orally disintegrating tablets (ODT) is the use of texture analyzer instrument. Once the method is able to provide good in vitro in vivo correlation (IVIVC) in the case of different tablets, it might be able to predict the oral disintegration time of similar products. However, there are many tablet parameters that influence the in vivo and the in vitro disintegration time of ODT products. Therefore, the measured in vitro and in vivo disintegration times can occasionally differ, even if they coincide in most cases of the investigated products and the in vivo disintegration times may also change if the aimed patient group is suffering from a special illness. If the method is no longer able to provide good IVIVC, then the modification of a single instrumental parameter may not be successful and the in vitro method must be re-set in a complex manner in order to provide satisfactory results. In the present experiment, an optimization process was developed based on texture analysis measurements using five different tablets in order to predict their in vivo disintegration times, and the optimized texture analysis method was evaluated using independent tablets. PMID:23558313

Szakonyi, G; Zelkó, R



Fast disintegrating tablets: Opportunity in drug delivery system  

PubMed Central

Fast disintegrating tablets (FDTs) have received ever-increasing demand during the last decade, and the field has become a rapidly growing area in the pharmaceutical industry. Oral drug delivery remains the preferred route for administration of various drugs. Recent developments in the technology have prompted scientists to develop FDTs with improved patient compliance and convenience. Upon introduction into the mouth, these tablets dissolve or disintegrate in the mouth in the absence of additional water for easy administration of active pharmaceutical ingredients. The popularity and usefulness of the formulation resulted in development of several FDT technologies. FDTs are solid unit dosage forms, which disintegrate or dissolve rapidly in the mouth without chewing and water. FDTs or orally disintegrating tablets provide an advantage particularly for pediatric and geriatric populations who have difficulty in swallowing conventional tablets and capsules. This review describes various formulations and technologies developed to achieve fast dissolution/dispersion of tablets in the oral cavity. In particular, this review describes in detail FDT technologies based on lyophilization, molding, sublimation, and compaction, as well as approaches to enhancing the FDT properties, such as spray drying and use of disintegrants. In addition, taste-masking technologies, experimental measurements of disintegration times, and dissolution are also discussed. PMID:22247889

Parkash, Ved; Maan, Saurabh; Deepika; Yadav, Shiv Kumar; Hemlata; Jogpal, Vikas



Formulation design of a novel fast-disintegrating tablet.  


As our society is becoming increasingly aged, the development of an appropriate dosage form for the elderly patients is mostly desirable. A novel fast-disintegrating tablet was investigated in this study as a user-friendly dosage form for the aged. Advantages of this formulation have sufficient hardness and can be manufactured by commonly used equipment. Saccharides can be divided into high- and low-compressibility categories, and an appropriate material for fast-disintegrating tablets was created by taking advantage of this fact. To improve the compressibility of low-compressibility saccharides, particle modification was conducted by coating and granulating a low-compressibility saccharide with a high one to enable the production of a fast-disintegrating tablet. Another discovery was that the high-compressibility saccharide used as a binder solution was present in an amorphous state after the granulation process. The crystal change from amorphous to crystal state intentionally by a conditioning process after compression enabled to increase tablet hardness by strengthening adhesion between particles. The conditioning process made it possible to achieve sufficient hardness while maintaining the fast disintegration time. As a result, this fast-disintegrating tablet that can be manufactured by commonly used equipment, can be used for the dosing of a wide range drugs. PMID:16257154

Mizumoto, Takao; Masuda, Yoshinori; Yamamoto, Takeshi; Yonemochi, Estuo; Terada, Katsuhide



Effect of powder characteristics on oral tablet disintegration.  


This report describes an investigation of the factors affecting disintegration time in the mouth (DTM) of rapidly disintegrating tablets. The relation between DTM and stationary time of upper punch displacement (STP) was examined using a tableting process analyzer (TabAll). Results indicated that the bulk density of mixed excipient powder used for tablet preparation affects both DTM and STP. As the value of bulk density increased, STP became longer and DTM shorter. The results of a combination of granules and powder with or without a drug showed liner relation between apparent volume (reciprocal of bulk density) and DTM (r(2)=0.7332). For a DTM less than 60 s, a formulation with a bulk density greater 0.5 g/mL should be chosen with a compression force of 5 kN. The hardness of tablets could be greater than 3 kg if at least one high-compressibility excipient was used in the formulation. PMID:18804156

Yamamoto, Yoshihisa; Fujii, Makiko; Watanabe, Ken-ichi; Tsukamoto, Masashi; Shibata, Yusuke; Kondoh, Masuo; Watanabe, Yoshiteru



Design and evaluation of taste masked dextromethorphan hydrobromide oral disintegrating tablets.  


The present study is aimed to develop dextromethorphan hydrobromide (DXM) oral disintegrating tablets (ODT) with acceptable palatability to help patients of all age groups. The bitter taste of the drug was masked by binding the drug to ion exchange resin. The effect of the particle size of resin on drug loading was studied. In vitro and in vivo disintegration time and in vitro drug release studies were performed. Drug loading increased significantly with a decrease in the particle size of the resin. DSC and XRPD studies reveal that the molecular state of the drug changed from crystalline to amorphous form. The dissolution efficiency calculated for optimized ODT and conventional directly compressed tablet were almost comparable, indicating free dissociation of the drug from the resinate. The bitter taste of DXM can be masked by binding with ion exchange resin and the resinate can be successfully formulated into oral disintegrating tablets. PMID:21134862

Malladi, Madhusudhan; Jukanti, Raju; Nair, Rashmi; Wagh, Sanjay; Padakanti, Hari Shanker; Mateti, Ashok



Investigation of Formulation and Process of Lyophilised Orally Disintegrating Tablet (ODT) Using Novel Amino Acid Combination  

PubMed Central

Lyophilised orally disintegrating tablets (ODTs) have achieved a great success in overcoming dysphagia associated with conventional solid dosage forms. However, the extensive use of saccharides within the formulation limits their use in treatment of chronic illnesses. The current study demonstrates the feasibility of using combination of proline and serine to formulate zero sacharide ODTs and investigates the effect of freezing protocol on sublimation rate and tablets characteristics. The results showed that inclusion of proline and serine improved ODT properties when compared to individual counterparts. Additionally, annealing the ODTs facilitated the sublimation process and shortened the disintegration time.

AlHusban, Farhan; ElShaer, Amr M.; Kansara, Jiteen H.; Smith, Alan M.; Grover, Liam M.; Perrie, Yvonne; Mohammed, Afzal R.



Further improvement of orally disintegrating tablets using micronized ethylcellulose.  


The aim of this study is to design a new orally disintegrating tablet (ODT) containing micronized ethylcellulose (MEC). The new ODT was prepared by physical mixing of rapidly disintegrating granules (RDGs) with MEC. To obtain RDGs, mannitol was spray-coated with a suspension of corn starch and crospovidone (9:1, w/w ratio) using a fluidized-bed granulator (suspension spray-coating method). The new ODTs were evaluated for their hardness, friability, thickness, internal structure (X-ray-CT scanning), in vivo disintegration time, and water absorption rate. Since MEC increases tablet hardness by increasing the contact frequency between the granules, the new ODTs could obtain high hardness (>50 N) and low friability (<0.5 %) with relatively low compression force. In addition, fine capillary channels formed in ODTs facilitated the wicking action and enabled rapid disintegration in vivo (<30 s). On the other hand, since MEC has low hygroscopicity, the tablet hardness of ODTs containing MEC remained high for 1 month in high-humidity conditions. In conclusion, the new ODTs containing MEC developed in this study possessed superior properties for clinical use and are expected to be applied for a wide range of functionally released drugs for bitter taste masking, sustained release, and controlled release (pH-dependent film coating, matrix, and microcapsule). PMID:22138608

Okuda, Yutaka; Irisawa, Yosuke; Okimoto, Kazuto; Osawa, Takashi; Yamashita, Shinji



Application of a novel automatic disintegration apparatus for the development and evaluation of a direct compression rapidly disintegrating tablet.  


An automatic disintegration tester was developed and used to explore disintegration mechanism and times of rapidly disintegrating tablets. DT50, the time required for a tablet to decrease in its thickness by half, allowed an unbiased determination of disintegration time. Calcium silicate concentration, Explotab® concentration, DiPac®/Xylitab® ratio as fillers, and compression pressure were evaluated using a central composite model design analysis for their DT50, tensile strength, and friability. Tablets that could reasonably be handled (friability <10%) could be produced. The expansion coefficient (n) and the exponential rate constant (k) for disintegrating tablets, originally measured by Caramella et al. using force kinetics, could be determined from axial displacement data measured directly without the need to assume that disintegration force generation was indicative of changes in tablet volume. The n values of tablets containing calcium silicate, Ditab® and/or Xylitab®, magnesium stearate, and Explotab® suggested that the amount of Explotab® was not a significant factor in determining the disintegration mechanism; however, the type of disintegrant used did alter the n value. Primojel® and Explotab®, which are in the same class of disintegrants, exhibited similar DT50, n, and k. Polyplasdone® XL exhibited a much higher n, while yielding faster DT50, suggesting that its performance is more dependent on facilitating the interfacial separation of particles. AcDiSol® showed no apparent moisture sensitivity in regards to disintegration efficiency. The use of the novel apparatus proved to be useful in measuring disintegration efficiency of rapidly disintegrating tablets and in providing valuable information on the disintegration phenomena. PMID:22091970

Jung, Huijeong Ashley; Augsburger, Larry L



Disintegration of highly soluble immediate release tablets: a surrogate for dissolution.  


The purpose of the work was to investigate correlation between disintegration and dissolution for immediate release tablets containing a high solubility drug and to identify formulations where disintegration test, instead of the dissolution test, may be used as the acceptance criteria based on International Conference on Harmonization Q6A guidelines. A statistical design of experiments was used to study the effect of filler, binder, disintegrating agent, and tablet hardness on the disintegration and dissolution of verapamil hydrochloride tablets. All formulation variables, i.e., filler, binder, and disintegrating agent, were found to influence tablet dissolution and disintegration, with the filler and disintegrating agent exerting the most significant influence. Slower dissolution was observed with increasing disintegration time when either the filler or the disintegrating agent was kept constant. However, no direct corelationship was observed between the disintegration and dissolution across all formulations due to the interactions between different formulation components. Although all tablets containing sodium carboxymethyl cellulose as the disintegrating agent, disintegrated in less than 3 min, half of them failed to meet the US Pharmacopeia 30 dissolution criteria for the verapamil hydrochloride tablets highlighting the dependence of dissolution process on the formulation components other than the disintegrating agent. The results identified only one formulation as suitable for using the disintegration test, instead of the dissolution test, as drug product acceptance criteria and highlight the need for systematic studies before using the disintegration test, instead of the dissolution test as the drug acceptance criteria. PMID:19387843

Gupta, Abhay; Hunt, Robert L; Shah, Rakhi B; Sayeed, Vilayat A; Khan, Mansoor A



Fabrication and optimization of fast disintegrating tablets employing interpolymeric chitosan-alginate complex and chitin as novel superdisintegrants.  


The objective of the present work was to optimize the formulation of fast disintegrating tablets (FDTs) of ondansetron HCl containing novel superdisintegrants, possessing sufficient mechanical strength and disintegration time comparable to those containing crospovidone or croscarmellose sodium. The FDTs were formulated using a novel superdisintegrant (chitosan-alginate (1:1) interpolymer complex and chitin) to achieve a sweet tasting disintegrating system. The results revealed that chitin (5-20%) increased the porosity and decreased the DT of tablets. At higher concentrations chitin maintained tablet porosity even at 5.5 kg crushing strength. Ondansetron HCl was found to antagonize the wicking action of glycine. Further, evaluation of the mechanism of disintegration revealed that glycine transported the aqueous medium to different parts of the tablets while the chitosan-alginate complex swelled up due to transfer of moisture from glycine. This phenomenon resulted in breakage of the tablet within seconds. For preparing optimized FDTs, the reduced model equations generated from Box-Behnken design (BBD) were solved after substituting the known disintegration time of FDTs containing superdisintegrants in the reduced model equations. The results suggested that excipient system under investigation not only improved the disintegration time but also made it possible to prepare FDTs with higher crushing strength as compared to tablets containing known superdisintegrants. PMID:21796940

Goel, Honey; Tiwary, Ashok K; Rana, Vikas



Effects of Magnesium Hydroxide on Disintegration Time and Dissolution Rate of Diclofenac Sodium Plain Tablet  

Microsoft Academic Search

The objective of this study was to evaluate the effects of magnesium hydroxide (MH) on disintegration time (DT) and dissolution profile of diclofenac sodium (DS) plain tablet. The tablets of DS were formulated with conventionally used excipients and investigational agent Mg (OH) 2 . Different parameters of tablets like hardness, thickness, friability, and disintegration time and dissolution rate were determined

Miazi MMH; Choudhury MMA; Rahman MH



Formulation and evaluation of taste-masked levocetirizine dihydrochloride orally disintegrating tablets.  


Orally disintegrating tablets of levocetirizine dihydrochloride were formulated with different superdisintegrants (sodium starch glycollate, croscarmellose sodium, and crospovidone) using mannitol as a diluent. Tulsion-335, Indion-204, and poly kyron T-134 cation exchange resins were used as taste-masking agents. The drug and resin complex was prepared by the kneading method. Ten formulations were prepared with varying combinations of superdisintegrants and ion-exchange resins by the wet granulation technique, using polyvinylpyrrolidone K-30 as the binder. The prepared tablets were evaluated for degree of taste masking, weight variation, hardness, friability, in vitro and in vivo disintegration time, content uniformity, and water absorption ratio. Dissolution studies were performed in two dissolution media: 0.1N HCl and distilled water. The corresponding dissolution rates were compared with the marketed formulation. Differential scanning calorimetry studies were carried out on the drug-resin complexes. Prepared tablets were good in appearance and showed acceptable results for hardness and friability. In vitro and in vivo disintegration times for the optimum formulation (F-1) were found to be 22 and 55 s, respectively. Relatively acceptable taste was achieved with both Indion-204 and Tulsion-335. Rapid disintegration time was achieved in tablets containing crosspovidone as the superdisintegrant. Dissolution studies indicated the formation of the complex of drug and resin. Differential scanning calorimetry studies indicated the formation of drug-resin complex. PMID:20169858

Devireddy, Srinivas Reddy; Gonugunta, Chandra Sekhara Rao; Veerareddy, Prabhakar Reddy



Improved stability of Opalmon tablets under humid conditions IV: effect of polysaccharides and disintegrants on the stability and dissolution property of Opalmon tablets.  


We studied the effects of dextran, dextrin, and disintegrants on the chemical stability of Opalmon tablets containing Limaprost-alfadex (Limaprost/alpha-cyclodextrin complex) and found that the addition of dextran or dextrin significantly improved the chemical stability of Opalmon tablets under high humidity, compared to lactose. We also examined how dextran stabilizes Limaprost in Opalmon tablets and studied the formulation of Opalmon tablets in order to achieve higher chemical stability, rapid dissolution and reduced stickiness. The results suggested that dextran increases stabilization after moisture adsorption by decreasing the dissociation of Limaprost-alfadex to the free drug and alpha-cyclodextrin in the dextran matrix, when compared with the lactose matrix. The stickiness of Opalmon tablets containing dextran and dextrin was negligible when dextran and dextrin amounted to less than 20% of the formulation. By selecting a proper disintegrant, we obtained Opalmon tablets with higher chemical stability and rapid dissolution properties. PMID:18175966

Sekiya, Noboru; Nishiwaki, Atsushi; Nishiura, Akio; Yamamoto, Masanobu; Takeda, Kazuhisa; Iohara, Daisuke; Hirayama, Fumitoshi; Arima, Hidetoshi; Uekama, Kaneto



Evaluation of the disintegration time of rapidly disintegrating tablets via a novel method utilizing a CCD camera.  


Many kinds of rapidly disintegrating or oral disintegrating tablets (RDT) have been developed to improve the ease of tablet administration, especially for elderly and pediatric patients. In these cases, knowledge regarding disintegration behavior appears important with respect to the development of such a novel tablet. Ordinary disintegration testing, such as the Japanese Pharmacopoeia (JP) method, faces limitations with respect to the evaluation of rapid disintegration due to strong agitation. Therefore, we have developed a novel apparatus and method to determine the dissolution of the RDT. The novel device consists of a disintegrating bath and CCD camera interfaced with a personal computer equipped with motion capture and image analysis software. A newly developed RDT containing various types of binder was evaluated with this protocol. In this method, disintegration occurs in a mildly agitated medium, which allows differentiation of minor distinctions among RDTs of different formulations. Simultaneously, we were also able to detect qualitative information, i.e., morphological changes in the tablet during disintegration. This method is useful for the evaluation of the disintegration of RDT during pharmaceutical development, and also for quality control during production. PMID:12237533

Morita, Yutaka; Tsushima, Yuki; Yasui, Masanobu; Termoz, Ryoji; Ajioka, Junko; Takayama, Kozo



Stability of benzocaine formulated in commercial oral disintegrating tablet platforms.  


Pharmaceutical excipients contain reactive groups and impurities due to manufacturing processes that can cause decomposition of active drug compounds. The aim of this investigation was to determine if commercially available oral disintegrating tablet (ODT) platforms induce active pharmaceutical ingredient (API) degradation. Benzocaine was selected as the model API due to known degradation through ester and primary amino groups. Benzocaine was either compressed at a constant pressure, 20 kN, or at pressure necessary to produce a set hardness, i.e., where a series of tablets were produced at different compression forces until an average hardness of approximately 100 N was achieved. Tablets were then stored for 6 months under International Conference on Harmonization recommended conditions, 25°C and 60% relative humidity (RH), or under accelerated conditions, 40°C and 75% RH. Benzocaine degradation was monitored by liquid chromatography-mass spectrometry. Regardless of the ODT platform, no degradation of benzocaine was observed in tablets that were kept for 6 months at 25°C and 60% RH. After storage for 30 days under accelerated conditions, benzocaine degradation was observed in a single platform. Qualitative differences in ODT platform behavior were observed in physical appearance of the tablets after storage under different temperature and humidity conditions. PMID:23990120

Köllmer, Melanie; Popescu, Carmen; Manda, Prashanth; Zhou, Leon; Gemeinhart, Richard A



Effect of starch 1500 as a binder and disintegrant in lamivudine tablets prepared by high shear wet granulation.  


High shear wet granulation is a preferred manufacturing method of tablets. It allowed for rapid production of compressible granulations. The resultant granulation characteristics depend on a combination of formulation properties and processing parameters. Fully pregelatinized starches are currently being used as binders in wet granulated formulations. But due to the gelatinization, much of the disintegration properties are lost. Partially pregelatinized starches (starch 1,500) have a mixture of properties of both native and fully gelatinized starches; made them useful as both a binder and a disintegrant in wet granulated formulations. Starch 1,500 performed as an excellent binder producing a granulation that was compressible and produced lamivudine tablets of improved hardness and friability compared with those prepared with povidone. The formulation of lamivudine tablets with starch 1,500 exceeded the disintegration and dissolution performance of the povidone formulation that utilized a super disintegrant. High shear wet granulation is also well suited for the use of partially pregelatinized starches. PMID:18930870

Rahman, Bytul M; Ibne-Wahed, Mir Imam; Khondkar, Proma; Ahmed, Maruf; Islam, Robiul; Barman, Ranjan K; Islam, M Anwarul



Bio-predictive tablet disintegration: effect of water diffusivity, fluid flow, food composition and test conditions.  


Food intake may delay tablet disintegration. Current in vitro methods have little predictive potential to account for such effects. The effect of a variety of factors on the disintegration of immediate release tablets in the gastrointestinal tract has been identified. They include viscosity of the media, precipitation of food constituents on the surface of the tablet and reduction of water diffusivity in the media as well as changes in the hydrodynamics in the surrounding media of the solid dosage form. In order to improve the predictability of food affecting the disintegration of a dosage form, tablet disintegration in various types of a liquefied meal has been studied under static vs. dynamic (agitative) conditions. Viscosity, water diffusivity, osmolality and Reynolds numbers for the different media were characterized. A quantitative model is introduced which predicts the influence of the Reynolds number in the tablet disintegration apparatus on the disintegration time. Viscosity, water diffusivity and media flow velocity are shown to be important factors affecting dosage form disintegration. The results suggest the necessity of considering these parameters when designing a predictive model for simulating the in vivo conditions. Based on these experiments and knowledge on in vivo hydrodynamics in the GI tract, it is concluded that the disintegration tester under current pharmacopoeial conditions is operated in an unphysiological mode and no bioprediction may be derived. Recommendations regarding alternative mode of operation are made. PMID:24036239

Radwan, Asma; Wagner, Manfred; Amidon, Gordon L; Langguth, Peter



A new formulation for orally disintegrating tablets using a suspension spray-coating method.  


The aim of this study was to design a new orally disintegrating tablet (ODT) that has high tablet hardness and a fast oral disintegration rate using a new preparation method. To obtain rapid disintegration granules (RDGs), a saccharide, such as trehalose, mannitol, or lactose, was spray-coated with a suspension of corn starch using a fluidized-bed granulator (suspension method). As an additional disintegrant, crospovidone, light anhydrous silicic acid, or hydroxypropyl starch was also included in the suspension. The RDGs obtained possessed extremely large surface areas, narrow particle size distribution, and numerous micro-pores. When tabletting these RDGs, it was found that the RDGs increased tablet hardness by decreasing plastic deformation and increasing the contact frequency between granules. In all tablets, a linear relationship was observed between tablet hardness and oral disintegration time. From each linear correlation line, a slope (D/H value) and an intercept (D/H(0) value) were calculated. Tablets with small D/H and D/H(0) values could disintegrate immediately in the oral cavity regardless of the tablet hardness and were considered to be appropriate for ODTs. Therefore, these values were used as key parameters to select better ODTs. Of all the RDGs prepared in this study, mannitol spray-coated with a suspension of corn starch and crospovidone (2.5:1 w/w ratio) showed most appropriate properties for ODTs; fast in vivo oral disintegration time, and high tablet hardness. In conclusion, this simple method to prepare superior formulations for new ODTs was established by spray-coating mannitol with a suspension of appropriate disintegrants. PMID:19686825

Okuda, Y; Irisawa, Y; Okimoto, K; Osawa, T; Yamashita, S



Formulation Development and evaluation of fast disintegrating tablets of Lamotrigine using liqui-solid technique  

PubMed Central

Introduction: Epilepsy is a serious neurological disorder. Lamotrigine is an alternative to lithium for the treatment of epilepsy, and its oral bioavailability is 98%; however, its poor aqueous solubility hinders its oral absorption. Among the techniques available to enhance the solubility, dissolution rate and bio availability of poorly soluble drugs, liqui-solid technique is a novel and promising approach. The objectives of the investigation are to formulate, optimize lamotrigine liqui-solid compacts using 23 factorial experiments, validate experimental designs statistically and to compare with the marketed tablets using similarity and difference factors. Materials and Methods: Based on solubility studies tween 20 as nonvolatile liquid, avicel pH 101 as a carrier and aerosil 200 as a coating material were used. Liquid load factor other flow and compression characteristics were determined for different ratios of carrier and coat materials. Suitable quantities of carrier and coat materials were taken, according to the experimental designs other excipients were added, liqui-solid tablets were prepared by direct compression and evaluated. Drug excipient compatibility was determined using Fourier transform infrared spectroscopy (FTIR) analysis. The hardness, disintegration time and T75% were considered for validation of experimental designs. Results: The physicochemical properties of tablets such as hardness (1.5 ± 0.8–4.95 ± 0.96 kg), in vitro disintegration time (40 ± 20–320 ± 25 s) and Friability (0.39 ± 0.5–1.45 ± 0.2% also <1%) possess all the Indian pharmacopoeal requirements. The T75% was calculated and found to be 6.62–22.8 min. The rate of drug release followed first order kinetics. f1 and f2 values indicated the similarity in dissolution profiles between marketed and the optimized formulation and 63.64% similar with that of the marketed fast disintegrating tablets. FTIR studies revealed the absence of drug excipient incompatibility.

Koteswari, Poluri; Sunium, Suvarnala; Srinivasababu, Puttugunta; Babu, Govada Kishore; Nithya, Pinnamraju Durga



Fast disintegrating crystalline solid dispersions of simvastatin for incorporation into orodispersible tablets  

PubMed Central

Aim: Spray dried solid dispersion (SDP) of crystalline simvastatin (SIM) in a fast disintegrating matrix of superdisintegrants was studied as a method to enhance SIM dispersibility, rheology, compactibility and compressibility for incorporation into orodispersible tablets (ODTs). Materials and Methods: The superdisintegrants investigated were crospovidone (CP), sodium starch glycollate (SSG) and calcium silicate (CS) were spray dried with simvastatin to form SDPs. Results: The SDPs were characterized and the median particle size of SDPs was similar or greater than the SIM, contributing to good rheology of SDPs, while the low bulk density of SDPs indicated a high compactibility. Interestingly electron micrographs for SDPs showed a CP or CS carrier coating of the SIM crystals, contributing to its rheology. Thermal analysis and X-ray diffraction confirmed that SIM was crystalline in the SDPs and no interaction between SIM and any of the carrier(s) was shown by Fourier transform-infra red. Drug content analysis showed a SIM content of 90-95% in SDPs containing CP or CS, while a higher SIM content of 143% was found in SDP containing SSG. When formulated as ODTs, blend containing SIM SDPs in CP showed ease of tableting, regardless of the turret speed. In comparison, tablet blend consisting of a physical mix (PM) of SIM and CP could only be tableted at the lower turret speed of 7 rpm. ODTs formulated using SIM SDPs in CP showed a higher extent of dissolution, compared to the ODTs containing corresponding PM or the commercially available SIM Zocor® tablets (ANOVA, P < 0.05). Conclusion: SDP using disintegrants as carriers may offer an alternative formulation approach for ODTs of poorly soluble drugs. PMID:25006549

Pabari, Ritesh M; Jamil, Asha; Kelly, John G; Ramtoola, Zebunnissa



Formulation and evaluation of diclofenac potassium fast-disintegrating tablets and their clinical application in migraine patients.  


The aim of this study was to prepare fast-disintegrating tablets (FDTs) of diclofenac potassium with sufficient integrity as well as a pleasant taste, using two different fillers and binders: Tablettose 70(®) and Di-Pac(®). Tablets were made with direct compression method. Tablet properties such as porosity, hardness, and disintegration time were determined. Diclofenac potassium determinations were carried out using a validated spectrophotometric method for the analysis of drug. Furthermore, in vivo experiments were carried out to compare the analgesic effect and the time to relieve migraine headache between the commercial tablets and FDTs of diclofenac potassium against placebo. Results showed that FDTs of diclofenac potassium with durable structure and desirable taste can be prepared using both fillers and binders but tablets prepared with Di-Pac had a better taste so the tablet formulation containing Di-Pac was chosen for in vivo experiments. Placebo controlled in vivo trial demonstrated that 50 mg diclofenac potassium, administered as a single dose of FDTs or commercial tablets, was effective in relieving the pain and both of them were superior to placebo. PMID:20704458

Comoglu, Tansel; Dogan, Aysegul; Comoglu, Selcuk; Basci, Nursabah



Development and optimization of dextromethorphan hydrobromide oral disintegrating tablets: effect of formulation and process variables.  


Orally disintegrating tablets (ODTs), which disintegrate rapidly (<1?min) in the mouth and do not require water for administration, have become a very popular dosage form. The study aims to develop a simple and inexpensive method of manufacturing ODTs of a sparingly water-soluble drug, Dextromethorphan hydrobromide. Two factors, three levels (3(2)) full factorial design was used to optimize the diluent, microcrystalline cellulose (X(1)) and superdisintegrant, croscarmellose sodium (X(2)) concentrations. Disintegration time, hardness and T(50) values for all the formulations varied from 12.5 to 152.6 s, 3.58 to 4.92 kp and 0.8 to 2.8?min, respectively. The results indicated that the selected variables have a strong influence on disintegration time, hardness and T(50) of the ODTs. The manufactured ODTs formula composed of 30% microcrystalline cellulose in combination with 3% croscarmellose sodium was chosen as optimized formula, as it showed the lowest disintegration time (12.5?±?1.22 s), low T(50) (0.8?min.) and hard tablets (4.92?±?0.28 kp) amongst other tested ODTs formulations. Hardness of DM ODTs was not affected by changing the type of superdisintegrant and lubricant. The disintegration time was significantly (p < 0.05) increased by using sodium starch glycolate instead of croscarmellose sodium. PMID:22881389

Mostafa, Haitham Fady; Ibrahim, Mohamed Abbas; Sakr, Adel



Preparation and evaluation of taste-masked dextromethorphan oral disintegrating tablet.  


This study was aimed at preparing and evaluating oral disintegrating tablets (ODTs) using a strongly cationic resin, Amberlite(®) IRP-69, to mask the bitter taste of a delivered drug, i..e. dextromethorphan hydrobromide. The drug was loaded into the resin (referred to as resinate) or physically mixed with the resin (referred to as physical mixture), and was then incorporated into ODTs by direct compression. A variety of formulae was developed to acquire the optimal formulations of taste-masked ODTs that had acceptable hardness and mouth feel (grittiness). The optimized ODTs were further evaluated for thickness, diameter, weight, friability, disintegration time, wetting time, wetting rate, drug content, drug release and degree of bitter taste, respectively. The thickness, diameter, weight and friability of the tablet with resinate were slightly higher than those with physical mixture. The tablet with resinate had a longer disintegration time, corresponding with its slower wetting time and rate. Both tablets with resinate and physical mixture provided a sustained pattern of drug release. However, only tablets with resinate successfully masked the bitter taste of the drug. In conclusion, the combination of drug and ion exchange resin as resinate could increase the palatability and acceptability of ODTs containing bitter drugs. PMID:21142821

Samprasit, Wipada; Opanasopit, Praneet; Akkaramongkolporn, Prasert; Ngawhirunpat, Tanasait; Wongsermsin, Kaewnapa; Panomsuk, Suwannee



Development of Corn Starch-Neusilin UFL2 Conjugate as Tablet Superdisintegrant: Formulation and Evaluation of Fast Disintegrating Tablets.  


In the present study, corn Starch-Neusilin UFL2 conjugates were prepared by physical, chemical, and microwave methods with the aim of using the conjugates as tablet superdisintegrant. Various powder tests, namely, angle of repose, bulk density, tapped density, Hausner's ratio, Carr's index, swelling index, and powder porosity were conducted on the samples. The conjugates were characterized by ATR-FTIR, XRD, DSC, and SEM techniques. Heckel and Kawakita models were applied to carry out compression studies for the prepared conjugates. Fast disintegrating tablets of domperidone were prepared using corn starch and corn Starch-Neusilin UFL2 conjugates as tablet superdisintegrants in different concentrations. Conjugates were found to possess good powder flow and tabletting properties. Heckel analysis indicated that the conjugates prepared by microwave method showed the slowest onset of plastic deformation while Kawakita analysis indicated that the conjugates prepared by microwave method exhibited the highest amount of total plastic deformation. The study revealed that the corn Starch-Neusilin UFL2 conjugates possess improved powder flow properties and could be a promising superdisintegrant for preparing fast disintegrating tablet. Also, the results sugessted that the microwave method was found to be most effective for the preparation of corn Starch-Neusilin UFL2 conjugates. PMID:25328710

Juneja, Prateek; Kaur, Birender; Odeku, Oluwatoyin A; Singh, Inderbir



Development of Corn Starch-Neusilin UFL2 Conjugate as Tablet Superdisintegrant: Formulation and Evaluation of Fast Disintegrating Tablets  

PubMed Central

In the present study, corn Starch-Neusilin UFL2 conjugates were prepared by physical, chemical, and microwave methods with the aim of using the conjugates as tablet superdisintegrant. Various powder tests, namely, angle of repose, bulk density, tapped density, Hausner's ratio, Carr's index, swelling index, and powder porosity were conducted on the samples. The conjugates were characterized by ATR-FTIR, XRD, DSC, and SEM techniques. Heckel and Kawakita models were applied to carry out compression studies for the prepared conjugates. Fast disintegrating tablets of domperidone were prepared using corn starch and corn Starch-Neusilin UFL2 conjugates as tablet superdisintegrants in different concentrations. Conjugates were found to possess good powder flow and tabletting properties. Heckel analysis indicated that the conjugates prepared by microwave method showed the slowest onset of plastic deformation while Kawakita analysis indicated that the conjugates prepared by microwave method exhibited the highest amount of total plastic deformation. The study revealed that the corn Starch-Neusilin UFL2 conjugates possess improved powder flow properties and could be a promising superdisintegrant for preparing fast disintegrating tablet. Also, the results sugessted that the microwave method was found to be most effective for the preparation of corn Starch-Neusilin UFL2 conjugates. PMID:25328710

Juneja, Prateek; Kaur, Birender; Odeku, Oluwatoyin A.; Singh, Inderbir



Formulation and Evaluation of a Novel Matrix-Type Orally Disintegrating Ibuprofen Tablet  

PubMed Central

Orally disintegrating tablets (ODTs) are capable of turning quickly into a liquid dosage form in contact with the saliva, thus possessing the advantages of both the solid dosage forms particularly stability and liquid dosage forms specially ease of swallowing and pre-gastric absorption of drug. The aim of this study was to prepare a novel matrix-type buccal fast disintegrating ibuprofen tablet formulation using special polymers, water soluble excipients, super-disintegrants and quickly soluble granules. For this purpose different tablet formulations of ibuprofen were prepared. The amount of ibuprofen in each formulation was 100 mg. Eight groups of formulation were prepared (A-H series), accounting for a total number of 45 formulations. Formulations prepared were examined in terms of different physicochemical tests including powder/granule flowability, appearance, thickness, uniformity of weight, hardness, friability and disintegration time. Results of formulation F22a (in series F), was found to be acceptable, making it the chosen formulation for further studies. Then, by adding various flavorants and sweeteners to this formulation, complementary series of formulations, named G and H, were prepared. Following the comparison of their taste with each other through asking 10 volunteers, the most suitable formulation regarding the taste, being formulation F22s, was chosen as the ultimate formulation. This formulation had PVP, ibuprofen and croscarmellose as the intra-granular components and xylitol and saccharin as the extra-granular ingredients. Formulation F22s was found to be acceptable in terms of physicochemical tests conducted, showing quick disintegration within the buccal cavity, appropriate hardness and rather low friability. Hence formulation F22s was selected as the final formulation. PMID:24250378

Tayebi, Hoda; Mortazavi, Seyed Alireza



Formulation and In-vitro Evaluation of Orally Disintegrating Tablets of Olanzapine-2-Hydroxypropyl-?-Cyclodextrin Inclusion Complex  

PubMed Central

The aim of this study was to design orally disintegrating tablets of Olanzapine and to complex Olanzapine with 2-hydroxypropyl-?- cyclodextrin with special emphasis on disintegration and dissolution studies. Phase solubility studies demonstrated the formation of 1:1 molar inclusion complex by kneading method. Tablets were prepared by using superdisintegrants namely, sodium starch glycolate, croscarmellose sodium, crospovidone, tulsion 339, and indion 414. Complex was characterized using infrared spectroscopy, drug content estimation, saturated solubility study, diffrerential scanning calorimetry and X-ray diffractometry. 5% w/w croscarmellose sodium showed the minimum disintegration time 39 ± 1.76 sec and in-vitro drug release 99.19 ± 0.18% within 6 min. In general, solubility of Olanzapine can be improved by complexing with 2-hydroxypropyl-?- cyclodextrin. Croscarmellose sodium can be used for faster disintegration of tablets. PMID:24381598

Ajit Shankarrao, Kulkarni; Dhairysheel Mahadeo, Ghadge; Pankaj Balavantrao, Kokate



Controlled drug release of highly water-soluble pentoxifylline from time-limit disintegration-type wax matrix tablets.  


A pulsatile drug release system with a dry-coated tablet containing pentoxifylline was investigated for controlling drug release in the gastrointestinal tract. The system consisted of a core tablet with disintegrator and outer layer, which obtained compression from the ground mixtures of pentoxifylline and behenic acid. Drug release from a dry-coated tablet was investigated at 37 degrees C in JPXII 2nd fluid at pH 6.8. The drug release from the outer layer was fitted to the Cobby model. The drug release from the wax matrix increased significantly after tablet distintegration; therefore, the drug release profiles showed typical sigmoidal curves. The disintegration time depended on the weight fraction of the core tablet, and the drug release rate after disintegration increased with increasing drug concentration in the core tablet. The relationship between the time required for 50% drug release and the disintegration time was linear, indicating that the drug release rate was controlled by regulating the disintegration time. PMID:8008697

Otsuka, M; Matsuda, Y



Evidence-based nanoscopic and molecular framework for excipient functionality in compressed orally disintegrating tablets.  


The work investigates the adhesive/cohesive molecular and physical interactions together with nanoscopic features of commonly used orally disintegrating tablet (ODT) excipients microcrystalline cellulose (MCC) and D-mannitol. This helps to elucidate the underlying physico-chemical and mechanical mechanisms responsible for powder densification and optimum product functionality. Atomic force microscopy (AFM) contact mode analysis was performed to measure nano-adhesion forces and surface energies between excipient-drug particles (6-10 different particles per each pair). Moreover, surface topography images (100 nm2-10 µm2) and roughness data were acquired from AFM tapping mode. AFM data were related to ODT macro/microscopic properties obtained from SEM, FTIR, XRD, thermal analysis using DSC and TGA, disintegration testing, Heckel and tabletability profiles. The study results showed a good association between the adhesive molecular and physical forces of paired particles and the resultant densification mechanisms responsible for mechanical strength of tablets. MCC micro roughness was 3 times that of D-mannitol which explains the high hardness of MCC ODTs due to mechanical interlocking. Hydrogen bonding between MCC particles could not be established from both AFM and FTIR solid state investigation. On the contrary, D-mannitol produced fragile ODTs due to fragmentation of surface crystallites during compression attained from its weak crystal structure. Furthermore, AFM analysis has shown the presence of extensive micro fibril structures inhabiting nano pores which further supports the use of MCC as a disintegrant. Overall, excipients (and model drugs) showed mechanistic behaviour on the nano/micro scale that could be related to the functionality of materials on the macro scale. PMID:25025427

Al-Khattawi, Ali; Alyami, Hamad; Townsend, Bill; Ma, Xianghong; Mohammed, Afzal R



Development of novel sustained-release system, disintegration-controlled matrix tablet (DCMT) with solid dispersion granules of nilvadipine.  


The goal of this study is to develop a novel sustained-release (SR) system for poorly water-soluble drugs by applying solid dispersion (SD) technique for improving the solubility. The developed SR system, disintegration-controlled matrix tablet (DCMT), consists of hydrogenated soybean oil (HSO) as wax and SD granules containing low-substituted hydroxypropylcellulose (L-HPC) as a disintegrant. In this study, nilvadipine (NiD) was chosen as a model compound. Sustained-release profiles of NiD from DCMT were identically controlled in several dissolution mediums in spite of varying pH and agitation speed. The release of NiD from DCMT was sustained more effectively by increasing the amount of wax or by decreasing the amount of disintegrant, and supersaturation of NiD was achieved without any re-crystallization in dissolution medium. The release rate of NiD from DCMT was controlled by the disintegration rate of tablet. The release profile of NiD was described by the Hixson-Crowell's model better than zero-order kinetics, first-order kinetics and Higuchi's model, which supports that the release of NiD from DCMT is regulated by the disintegration of the tablet. From this study, it was clarified that DCMT was one of the promising SR systems applying SD for the poorly water-soluble drugs. PMID:16253377

Tanaka, Nobuyuki; Imai, Keiji; Okimoto, Kazuto; Ueda, Satoshi; Tokunaga, Yuji; Ohike, Atsuo; Ibuki, Rinta; Higaki, Kazutaka; Kimura, Toshikiro



Development of novel sustained-release system, disintegration-controlled matrix tablet (DCMT) with solid dispersion granules of nilvadipine (II): in vivo evaluation.  


A novel sustained-release (SR) system, disintegration-controlled matrix tablet (DCMT), was developed for poorly water-soluble drugs. DCMT, consisting of wax and solid dispersion (SD) granules containing a disintegrant, could control the release of nilvadipine (NiD), a model compound, by its disintegration. In the present study, two DCMTs (DCMT-1 and DCMT-2) with different release rates of NiD were orally administered to beagle dogs, and in vivo absorption of NiD from DCMTs was compared with that from immediate-release (IR) tablets. DCMTs successfully sustained the absorption of NiD longer than IR tablets, while they did not decrease the bioavailability of NiD. DCMT-2, providing the slower release of NiD than DCMT-1, prolonged the absorption longer than DCMT-1. In vivo absorption profiles of NiD from DCMTs were significantly correlated with in vitro release profiles, suggesting that the release property from DCMTs would maintain regardless of the change in physiological condition through the gastrointestinal tract. Furthermore, the food intake did not affect the absorption of NiD after oral administration of DCMT-2. The present results strongly indicate that the DCMT system would be a promising SR system, which could improve the solubility and sustain the absorption of poorly water-soluble drugs. PMID:16545477

Tanaka, Nobuyuki; Imai, Keiji; Okimoto, Kazuto; Ueda, Satoshi; Tokunaga, Yuji; Ibuki, Rinta; Higaki, Kazutaka; Kimura, Toshikiro



In vitro and in vivo correlation of disintegration and bitter taste masking using orally disintegrating tablet containing ion exchange resin-drug complex.  


Although the taste-masking of bitter drug using ion exchange resin has been recognized, in vitro testing using an electronic tongue (e-Tongue) and in vivo bitterness test by human panel test was not fully understood. In case of orally disintegrating tablet (ODT) containing bitter medicine, in vitro and in vivo disintegration is also importance for dosage performance. Donepezil hydrochloride was chosen as a model drug due to its bitterness and requires rapid disintegration for the preparation of ODT. In this study, ion exchange resin drug complex (IRDC) at three different ratios (1:2, 1:1, 2:1) was prepared using a spray-drying method and then IRDC-loaded ODT containing superdisintegrants (crospovidone, croscarmellose sodium, and sodium starch glycolate) were prepared by the direct compression method. The physical properties and morphologies were then characterized by scanning electron microscopy (SEM), X-ray powder diffraction (PXRD) and electrophoretic laser scattering (ELS), respectively. The in vitro taste-masking efficiency was measured with an electronic tongue (e-Tongue). In vivo bitterness scale was also evaluated by human volunteers and then we defined new term, "bitterness index (BI)" to link in vitro e-Tongue. There was a good correlation of IRDC between in vitro e-Tongue values and in vivo BI. Furthermore, IRDC-loaded ODT showed good in vitro/in vivo correlation in the disintegration time. The optimal IRDC-loaded ODTs displayed similar drug release profiles to the reference tablet (Aricept(®) ODT) in release media of pH 1.2, pH 4.0, pH 6.8 and distilled water but had significantly better palatability in vivo taste-masking evaluation. The current IRDC-loaded ODT according to the in vitro and in vivo correlation of disintegration and bitter taste masking could provide platforms in ODT dosage formulations of donepezil hydrochloride for improved patient compliances. PMID:23933050

Kim, Jong-Il; Cho, Sang-Min; Cui, Jing-Hao; Cao, Qing-Ri; Oh, Euichaul; Lee, Beom-Jin



Pharmacokinetic and bioequivalence comparison between orally disintegrating and conventional tablet formulations of flurbiprofen: A single-dose, randomized-sequence, open-label, two-period crossover study in healthy chinese male volunteers  

Microsoft Academic Search

Background: Flurbiprofen, an NSAID, is used for the treatment of inflammation and pain caused by rheumatoid arthritis and osteoarthritis as well as soft-tissue injuries. A new orally disintegrating tablet (ODT) of flurbiprofen has recently been developed; this study was conducted to provide support for this drug to obtain marketing authorization in China.Objective: The aim of the study was to compare

Yan-Mei Liu; Gang-Yi Liu; Yun Liu; Shui-Jun Li; Jing-Ying Jia; Meng-Qi Zhang; Chuan Lu; Yong-Mei Zhang; Xue-Ning Li; Chen Yu



Effect of polacrilin potassium as disintegrant on bioavailability of diclofenac potassium in tablets : a technical note.  


Polacrilin potassium is an ion exchange resin used in oral pharmaceutical formulations as a tablet disintegrant. It is a weakly acidic cation exchange resin. Chemically, it is a partial potassium salt of a copolymer of methacrylic acid with divinyl benzene. It ionizes to an anionic polymer chain and potassium cations. It was hypothesized that polacrilin potassium may be able to improve the permeability of anionic drugs according to the Donnan membrane phenomenon. The effect of polacrilin potassium on the permeability of diclofenac potassium, used as a model anionic drug, was tested in vitro using diffusion cells and in vivo by monitoring serum levels in rats. The amount of drug permeated across a dialysis membrane in vitro was significantly more in the presence of polacrilin potassium. Significant improvement was found in the extent of drug absorption in vivo. It could be concluded that polacrilin potassium may be used as a high-functionality excipient for improving the bioavailability of anionic drugs having poor gastrointestinal permeability. PMID:22585376

Bele, Mrudula H; Derle, Diliprao V



Application of the BCS biowaiver approach to assessing bioequivalence of orally disintegrating tablets with immediate release formulations.  


The aim of this study was to compare the dissolution profiles of oral disintegrating tablets (ODTs) and immediate release (IR) formulations in order to experimentally validate the regulatory biowaiver scheme (BWS) for biopharmaceutical classification system (BCS) class III drugs. We examined six drugs that show clinical bioequivalence between the ODTs and IR formulations: taltirelin, olopatadine, droxidopa, famotidine, fexofenadine, and hydrochlorothiazide. The dissolution profiles of these drugs were evaluated using the compendium paddle apparatus at pH 1.2 and 6.8. Taltirelin and olopatadine showed very rapid dissolution and met the dissolution criteria in the BWS, whereas droxidopa, famotidine, fexofenadine, and hydrochlorothiazide did not. Furthermore, in the case of famotidine, fexofenadine, and hydrochlorothiazide, the ODTs and IR formulations showed dissimilar dissolution profiles. The dose-to-solubility ratio (D:S) of these drugs was larger than that of the other drugs. The results of this study suggest that extension of the BCS-BWS to ODTs and IR formulations of BCS class III drugs is appropriate. Furthermore, for BCS class III drugs with relatively high D:S, clinical bioequivalence would be achievable even when two formulations showed different dissolution profiles in vitro. PMID:25151946

Ono, Asami; Sugano, Kiyohiko



Micronized ethylcellulose used for designing a directly compressed time-controlled disintegration tablet  

Microsoft Academic Search

Ethylcellulose (EC) of varying particle sizes has been used as an outer coating layer to design a novel dry-coated tablet with time-controlled drug release. This dry-coated tablet, containing a core tablet of sodium diclofenac and an outer coating layer of EC, was prepared by direct compression. The drug release from dry-coated tablet exhibited an initial lag period that was dependent

Shan-Yang Lin; Kung-Hsu Lin; Mei-Jane Li



Assessment of disintegrant efficacy with fractal dimensions from real-time MRI.  


An efficient disintegrant is capable of breaking up a tablet in the smallest possible particles in the shortest time. Until now, comparative data on the efficacy of different disintegrants is based on dissolution studies or the disintegration time. Extending these approaches, this study introduces a method, which defines the evolution of fractal dimensions of tablets as surrogate parameter for the available surface area. Fractal dimensions are a measure for the tortuosity of a line, in this case the upper surface of a disintegrating tablet. High-resolution real-time MRI was used to record videos of disintegrating tablets. The acquired video images were processed to depict the upper surface of the tablets and a box-counting algorithm was used to estimate the fractal dimensions. The influence of six different disintegrants, of different relative tablet density, and increasing disintegrant concentration was investigated to evaluate the performance of the novel method. Changing relative densities hardly affect the progression of fractal dimensions, whereas an increase in disintegrant concentration causes increasing fractal dimensions during disintegration, which are also reached quicker. Different disintegrants display only minor differences in the maximal fractal dimension, yet the kinetic in which the maximum is reached allows a differentiation and classification of disintegrants. PMID:25234864

Quodbach, Julian; Moussavi, Amir; Tammer, Roland; Frahm, Jens; Kleinebudde, Peter



An attempt to calculate in silico disintegration time of tablets containing mefenamic acid, a low water-soluble drug.  


Based on a Quality by Design (QbD) approach, it is important to follow International Conference on Harmonization (ICH) guidance Q8 (R2) recommendations to explore the design space. The application of an experimental design is, however, not sufficient because of the fact that it is necessary to take into account the effects of percolation theory. For this purpose, an adequate software needs to be applied, capable of detecting percolation thresholds as a function of the distribution of the functional powder particles. Formulation-computer aided design (F-CAD), originally designed to calculate in silico the drug dissolution profiles of a tablet formulation is, for example, a suitable software for this purpose. The study shows that F-CAD can calculate a good estimate of the disintegration time of a tablet formulation consisting of mefenamic acid. More important, F-CAD is capable of replacing expensive laboratory work by performing in silico experiments for the exploration of the formulation design space according to ICH guidance Q8 (R2). As a consequence, a similar workflow existing as best practice in the automotive and aircraft industry can be adopted by the pharmaceutical industry: The drug delivery vehicle can be first fully designed and tested in silico, which will improve the quality of the marketed formulation and save time and money. PMID:23613462

Kimura, Go; Puchkov, Maxim; Leuenberger, Hans



Rational estimation of the optimum amount of non-fibrous disintegrant applying percolation theory for binary fast disintegrating formulation.  


The purpose of this study was to propose a method of determining the exact value of disintegrant ratio in a binary drug-disintegrant compacted mixture for a minimum disintegration time in the case of spherical particles. Disintegration is a limiting factor in dissolution process of compact for low water soluble active ingredients. As disintegration time is shortest at a certain ratio of disintegrant, a calculation of this value is important for solid dosage from design to enhance disintegration and dissolution process. According to percolation theory, a minimum disintegration time corresponds to the formation of a continuous water-conducting cluster through the entire tablet. The critical volumetric ratio at which the cluster is formed is named percolation threshold and has the value of 0.16 for random close packed (RCP) sphere systems. RCP systems where chosen as the best model for compacts consisting of spherical particles. Two cases for water diffusion through the tablet were identified, according to geometrical considerations between disintegrant and drug particles. These cases determine if disintegrant particles can have a contact between each other within the compact and thus if porosity and disintegrant volume are included in the continuous cluster. An equation for both cases is presented in the form of piecewise function to determine the minimal disintegrant volumetric ratio for a binary drug/disintegrant compact in order to achieve a minimum disintegration time. Disintegration tests were performed with tablets at different ratios of modified corn starch mixed with caffeine or paracetamol powders. Estimated and experimental optimal ratio were compared showing coefficient R(2) = 0.96. PMID:17879295

Krausbauer, Etienne; Puchkov, Maxim; Betz, Gabriele; Leuenberger, Hans



A comparative study of dissolution characteristics of polymeric and wax granulations of theophylline and their tablets.  


Matrix (non disintegrating) granules of theophylline have been formed and their dissolution characteristics investigated for sustained release application. The polymeric granulations were formed by massing the drug powder with a concentrated (40% w/w) ethanolic solution of an acrylatemethacrylate copolymer (ERS100R). Wax granulations were also formed by massing the drug powder with previously melted carnuba wax followed by screening and drying. The content of polymer or wax in the resulting granules was 16.7% w/w. Conventional granules of theophylline were formed by massing the drug powder with starch mucilage (20% w/v). Resulting granules were subjected to particle size analysis and in vitro dissolution tests. The granules were further compressed to tablets (weight 500+/-4.2 mg each) at a constant load (30 arbitrary units on the load scale). The tablets were subjected to hardness, disintegration and dissolution tests. The dissolution kinetics were also considered. The mean granule size was 646.5+/-4.3 microm (conventional), 821.4+/-4.8 microm (polymeric granulations) and 892.7+/-5.4 microm (wax granulations), the matrix granules were therefore larger than the conventional granules. Dissolution of the granules generally followed a first order rate kinetic. The rate constant (k(1)) for the conventional, polymeric and wax granulations were (h(-1)): 0.53, 0.31 and 0.27 respectively. Thus, the wax granulations appeared to be more effective than the polymeric granulations in retarding drug release from the granules but the difference was not statistically significant (p>0.05). The tensile strength of tablets derived from the conventional, polymeric and wax granulations were (MNm(-2)) 0.85, 1.68 and 1.96 respectively, indicating that the matrix granules (compared with the conventional granules) produced harder tablets at the same compression load. The corresponding first order dissolution rate constants were (h(-1)): 0.46, 0.28 and 0.21. Thus, tableting of the matrix granules produced a slight but significant decrease in dissolution rates, attributable to the disintegration of the tablets to more compact particles. PMID:18614417

Uhumwangho, Michael U; Okor, Roland S



A comparative study of the dissolution characteristics of capsule and tablet dosage forms of melt granulations of paracetamol--diluent effects.  


The dissolution characteristics of melt granulations of paracetamol in capsule and tablet dosage form were compared to determine whether the dissolution characteristics of the granules can be actualized by formulating them as rapidly disintegrating tablets. The term melt granulation refers here to the wax-matrix granules that were formed by triturating the drug powder (paracetamol) with a melted carnauba wax. The matrix granules were admixed with diluents (lactose, alpha-cellulose or microcrystalline cellulose) also in granular form to prevent size separation during encapsulation or tableting. The granules were filled into hard gelatin capsules (mean content weight, 500 +/- 6.2 mg) or tableted (mean weight 500 +/- 5.1 mg, and tensile strength 1.36 +/- 0.2 to 1.7 +/- 0.3 MN/m2). The capsules and tablets were subjected to disintegration and in vitro dissolution tests. The dissolution data were analyzed on the basis of zero, first order rate kinetics and Higuchi square root of time relationship. The results showed that the dissolution profiles were generally consistent with a first order rate kinetics (r = 0.95). The first order dissolution rate constants of capsules and tablets of the matrix granules only (without diluents) were 0.31 +/- 0.02 min(-1) and 0.20 +/- 0.03 min(-1), respectively, indicating faster dissolution from the capsules. Therefore, the dissolution characteristics of the matrix particles were not intact after tableting. Addition of diluents to the capsule formulations had no effect on dissolution rates, whereas in the tablets, dissolution rates increased. For instance, inclusion of a diluent up to 50% w/w in the tablets increased the dissolution rate constants to 0.34 +/- 0.04 min(-1) (lactose), 0.42 +/- 0.02 min(-1) (alpha-cellulose), and 0.46 +/- 0.03 min(-1) (microcrystalline cellulose). Thus, alpha-cellulose and microcrystalline cellulose produced greater enhancer effect on the tablet dissolution rates compared to lactose. Both the capsules and the tablets disintegrated rapidly within 2 to 3 minutes. The dissolution enhancer effect of the diluents in the tablets only, relates to the aqueous swelling of the disintegrated particles. PMID:17665854

Uhumwangho, Michael U; Okor, Roland S



An in vitro and in vivo comparative study of directly compressed solid dispersions and freeze dried sildenafil citrate sublingual tablets for management of pulmonary arterial hypertension.  


Sildenafilcitrate (SILD) orodispersable sublingual tablets (ODSTs) have been developed using two comparative techniques for improving their oral disintegration, dissolution and bioavailability in order to manage acute attacks of pulmonary arterial hypertension (PAH). The techniques employed were direct compression of SILD-poloxamer 188 solid dispersions (SDs) and freeze drying using various excipients. The physicochemical and solid-state properties, as well as the dissolution behavior of the tablets were evaluated. Moreover, SILD bioavailability in human volunteers from the prepared ODSTs was compared to that of the conventional oral tablet. Incorporation of SD of poloxamer188 in sublingual tablets together with Pharmaburst using the direct compression technique enhanced the extent and dissolution rate of SILD with 100% of drug being dissolved after 7 minutes. However, the lyophilization process was superior in enhancing dissolution and 100% of SILD was dissolved after only one minute. Moreover, the in vivo study showed that the AUC???? of lyophilized tablets was significantly higher than that of directly compressed tablets, with bioavailability values of 159.81 and 140.85%, respectively, compared to the commercial oral product. PMID:23470352

Zayed, Reham; Kamel, Amany O; Shukr, Marwa; El-Shamy, Abd El-Hamid



A comparative study of development and symptoms among disintegrative psychosis and infantile autism with an without speech loss  

Microsoft Academic Search

To investigate clinical pictures and the validity of disintegrative psychosis (DP) as defined in ICD-9, 18 cases of DP were compared with 51 and 145 cases of infantile autism (IA) with and without speech loss, respectively, on clinical variables. The DP cases showed clearer regression after more satisfactory development than the IA cases with speech loss. Around age 7, about

Hiroshi Kurita; Michiko Kita; Yuko Miyake



Phase I trial of capecitabine rapidly disintegrating tablets and concomitant radiation therapy in children with newly diagnosed brainstem gliomas and high-grade gliomas  

PubMed Central

Background We conducted a phase I study to estimate the maximum tolerated dose and describe the dose-limiting toxicities and pharmacokinetics of oral capecitabine rapidly disintegrating tablets given concurrently with radiation therapy to children with newly diagnosed brainstem or high-grade gliomas. Methods Children 3–21 y with newly diagnosed intrinsic brainstem or high-grade gliomas were eligible for enrollment. The starting dose was 500 mg/m2, given twice daily, with subsequent cohorts enrolled at 650 mg/m2 and 850 mg/m2 using a 3 + 3 phase I design. Children received capecitabine at the assigned dose daily for 9 wks starting from the first day of radiation therapy (RT). Following a 2-wk break, patients received 3 courses of capecitabine 1250 mg/m2 twice daily for 14 days followed by a 7-day rest. Pharmacokinetic sampling was performed in consenting patients. Six additional patients with intrinsic brainstem gliomas were enrolled at the maximum tolerated dose to further characterize the pharmacokinetic and toxicity profiles. Results Twenty-four patients were enrolled. Twenty were fully assessable for toxicity. Dose-limiting toxicities were palmar plantar erythroderma (grades 2 and 3) and elevation of alanine aminotransferase (grades 2 and 3). Systemic exposure to capecitabine and metabolites was similar to or slightly lower than predicted based on adult data. Conclusions Capecitabine with concurrent RT was generally well tolerated. The recommended phase II capecitabine dose when given with concurrent RT is 650 mg/m2, administered twice daily. A phase II study to evaluate the efficacy of this regimen in children with intrinsic brainstem gliomas is in progress (PBTC-030). PMID:23592571

Kilburn, Lindsay B.; Kocak, Mehmet; Schaedeli Stark, Franziska; Meneses-Lorente, Georgina; Brownstein, Carrie; Hussain, Sazzad; Chintagumpala, Murali; Thompson, Patrick A.; Gururangan, Sri; Banerjee, Anuradha; Paulino, Arnold C.; Kun, Larry; Boyett, James M.; Blaney, Susan M.



A Randomized, Multicenter Study Comparing the Safety and Efficacy of Sodium Phosphate Tablets With 2L Polyethylene Glycol Solution Plus Bisacodyl Tablets for Colon Cleansing  

Microsoft Academic Search

OBJECTIVE:The safety and efficacy of NaP tablets have not been compared with 2L PEG lavage solution. A multicenter, investigator-blinded study was conducted to compare the colon-cleansing efficacy of a new NaP tablet formulation with that of 2L PEG solution plus bisacodyl tablets in adults undergoing colonoscopy.METHODS:A total of 481 patients were randomized to receive either 32 tablets (48 g) of

John F. Johanson; John W. Popp; Lawrence B. Cohen; Sandra R. Lottes; William P. Forbes; Kelli Walker; Edwin Carter; Bing Zhang; Martin Rose



Leaching of indium from obsolete liquid crystal displays: Comparing grinding with electrical disintegration in context of LCA  

SciTech Connect

Highlights: Black-Right-Pointing-Pointer Two pre-treatment methods, prior to leaching of indium from obsolete LCD modules, were described. Black-Right-Pointing-Pointer Conventional grinding and electrical disintegration have been evaluated and compared in the context of LCA. Black-Right-Pointing-Pointer Experimental data on the leaching capacity for indium and the electricity consumption of equipment were inputted into the LCA model in order to compare the environmental performance of each method. Black-Right-Pointing-Pointer An estimate for the environmental performance was calculated as the sum of six impact categories. Black-Right-Pointing-Pointer Electrical disintegration method outperforms conventional grinding in all impact categories. - Abstract: In order to develop an effective recycling system for obsolete Liquid Crystal Displays (LCDs), which would enable both the leaching of indium (In) and the recovery of a pure glass fraction for recycling, an effective liberation or size-reduction method would be an important pre-treatment step. Therefore, in this study, two different types of liberation methods: (1) conventional grinding, and (2) electrical disintegration have been tested and evaluated in the context of Life Cycle Assessment (LCA). In other words, the above-mentioned methods were compared in order to find out the one that ensures the highest leaching capacity for indium, as well as the lowest environmental burden. One of the main findings of this study was that the electrical disintegration was the most effective liberation method, since it fully liberated the indium containing-layer, ensuring a leaching capacity of 968.5 mg-In/kg-LCD. In turn, the estimate for the environmental burden was approximately five times smaller when compared with the conventional grinding.

Dodbiba, Gjergj, E-mail: [Department of System Innovation, Graduate School of Engineering, University of Tokyo (Japan); Nagai, Hiroki; Wang Lipang; Okaya, Katsunori; Fujita, Toyohisa [Department of System Innovation, Graduate School of Engineering, University of Tokyo (Japan)




E-print Network

and implementation of a tablet application for Autistic children. Autistic children show drastic improvement of Autistic children. #12;Seletos 3 TABLE OF CONTENTS 1 Introduction handwriting recognition technology [19]. Apple then redefined the tablet industry with its release of the i

Miles, Will


Comparative evaluation of the in vitro efficacy of lanthanum carbonate chewable tablets.  


The aims of this study were to systematically evaluate the effects of pH levels, phosphate concentrations, and tablet integrity on the phosphate binding profiles of lanthanum carbonate chewable tablets, and to compare the in vitro phosphate binding efficacy of one reference and two test products of lanthanum carbonate chewable tablets. Langmuir equation was utilized to calculate the binding constants k1 and k2 . The phosphate binding to the tablets of lanthanum carbonate product was pH dependent, with a faster binding rate at low pH. The crushed tablets bind phosphate more rapid. Compared with the whole tablets, the kinetic binding profiles from the crushed tablets were less variable under all conditions for both test and reference products. The phosphate level has a significant impact on the phosphate binding for both whole and crushed tablets under all pH conditions, with more binding at higher phosphate concentration. The phosphate binding profiles displayed significant difference among the products. For a crushed tablet, the phosphate binding to lanthanum reached equilibrium within 8 h under all conditions. The 90% confidence interval for the k2 ratio (test/reference) was well within the 80%-125% under all pH conditions. However, the k1 ratio varies from 54% to 144%. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 102:1370-1381, 2013. PMID:23334989

Yang, Yongsheng; Bykadi, Srikant; Carlin, Alan S; Shah, Rakhi B; Yu, Lawrence X; Khan, Mansoor A



Utilization of date syrup as a tablet binder, comparative study  

PubMed Central

The aim of this study was to investigate the possibility of using dates syrup as a tablet binder. Dates syrup (40%, 50%, 60% w/w dates syrup:water) was utilized for the granulation of sodium bicarbonate and calcium carbonate as examples for water-soluble and water-insoluble materials; correspondingly. Those two materials represent examples of bulky drugs as well. Starch paste (10% w/w starch in water) and sucrose syrup (50% w/w sucrose in water), the well-known tablet binders, were used in the granulation of the same materials for the sake of comparison. The granulations were evaluated with regard to particle size and particle size distribution, granule strength, bulk density, flowability, moisture content and compression behavior. In addition, tablets prepared and evaluated from these granules. Taste and flavor of the prepared tablet have been tested by seven healthy volunteers. Within the scope of this work, dates syrup showed excellent properties as a tablet binder in comparison to starch paste or sucrose syrup for the granulation of both water-soluble and water-insoluble materials. Also, better flavoring and masking taste have been noticed from an evaluation by human volunteers demonstrating the usefulness of the date syrup as sweetener and flavoring the tablets in addition to its use as binder. PMID:23960724

Alanazi, Fars Kaed



Differences in In Vitro Disintegration Time among Canadian Brand and Generic Bisphosphonates  

PubMed Central

The objective of this study was to compare the disintegration times among Canadian-marketed brand (alendronate 70?mg, alendronate 70?mg plus vitamin D 5600?IU, and risedronate 35?mg) and generic (Novo-alendronate 70?mg and Apo-alendronate 70?mg) once-weekly dosed bisphosphonates. All disintegration tests were performed with a Vanderkamp Disintegration Tester. Disintegration was deemed to have occurred when no residue of the tablet, except fragments of insoluble coating or capsule shell, was visible. Eighteen to 20 samples were tested for each bisphosphonate group. The mean (±standard deviation) disintegration times were significantly (P < 0.05) faster for Apo-alendronate (26 ± 5.6 seconds) and Novo-alendronate (13 ± 1.1 seconds) as compared to brand alendronate (147 ± 50.5 seconds), brand alendronate plus vitamin D (378 ± 60.5 seconds), or brand risedronate (101 ± 20.6 seconds). The significantly faster disintegration of the generic tablets as compared to the brand bisphosphonates may have concerning safety and effectiveness implications for patients administering these therapies. PMID:25349772

Olszynski, Wojciech P.; Adachi, Jonathan D.; Davison, K. Shawn



Preparation and comparative evaluation of sustained release metoclopramide hydrochloride matrix tablets.  


Metoclopramide hydrochloride (MCP) is commonly used for the management of gastrointestinal disorders. Frequent administration and the undesired side effects (extra pyramidal symptoms) of the drug on the central nervous system due to the fluctuations of its plasma concentrations may lead to patient incompliance, and hence, improper therapy. Therefore, the present work will be devoted to formulate the drug in sustained release formulations. MCP was incorporated in 12 formulae containing different polymers and/or different polymer ratios. These polymers were hydroxypropylmethyl cellulose (HPMC), carboxymethylcellulose (CMC) and ethyl cellulose (EC). Sodium starch glycolate (SSG) was added to some formulae in different amounts in order to soften and/or disintegrate the tablets. Both direct compression and granulation techniques were used to prepare the tablets. The physical properties were found to be satisfactory for all the formulae. The dissolution profiles of the tablets were constructed using the change-over method. The drug release involved a combination of both diffusion and polymer-chain relaxation mechanisms. The time required to release 50% of MCP ranged from 1.2 to more than 8 h. Direct compression and dry granulation techniques produced sufficient sustaining of the drug release. However, the pellets made by wet granulation released MCP in about 2 h, i.e., pelletization spheronization technique was not effective in sustaining the drug. PMID:23960711

Abdel-Rahman, Sayed I; Mahrous, Gamal M; El-Badry, Mahmoud



Evaluation of named binders in Rauwolfia vomitoria root tablets.  


Some physical properties of Rauwolfia vomitoria root tablets were studied. Tablet characteristics studied were: weight uniformity, tensile strength, friability, disintegration time and content uniformity. Tablet property varied depending on the type and concentration of the binder. The tablets had type and concentration of the binder. The tablets had acceptable hardness and friability profiles. Although tablets containing 150 mg R. vomitoria root had lower tensile strength values. All the tablets passed the B.P. disintegration time test of 15 min. Moreover tablets containing 150 mg R. vomitoria root disintegrated under 1 min. at 4% w/w binder concentration. PMID:10961024

Onunkwo, G C



Cefdinir: A comparative study of anhydrous vs. monohydrate form. Microstructure and tabletting behaviour.  


Anhydrous cefdinir (AC) vs. monohydrated cefdinir (MHC) was compared in order to be used as antimicrobial in therapeutics. Different techniques have been used to characterize physically AC and MHC, and also a complete microstructural analysis of raw materials was carried out. Cefdinir and Maltodextrin QDM 500 (3:2) formulations were compressed in order to obtain tablets with typical dose of Cefdinir, i.e. 300 mg. Dissolution profiles were obtained for both AC and MHC tablets. Finally tablet X-ray diffraction was performed to ensure the stability of the monohydrated form after tabletting being clearly different in both AC and MHC crystals. AC crystal structure was agreed with the known pattern of anhydrous Cefdinir described in the literature. Microstructural analysis showed large differences in specific surface area (SSA), confirmed by mercury intrusion. Crystal structures of both AC and MHC were stable under mixing, compression and storing processes. Dissolution profiles were faster for hydrate form, probably related to microstructural properties of the crystal which remained after tabletting. In conclusion, it is possible to isolate Cefdinir in two forms anhydrous and monohydrate, well characterized and differentiated. The use of this later improves dissolution of tablet dosage form due to the lack of interconversion during tablet manufacture. PMID:16846727

Cabri, Walter; Ghetti, Paolo; Alpegiani, Marco; Pozzi, Giovanni; Justo-Erbez, Angel; Pérez-Martínez, José Ignacio; Villalón-Rubio, Rosario; Monedero-Perales, M Carmen; Muñoz-Ruiz, Angel



The comparability of dosage regimens of Lanoxin tablets and Lanoxicaps.  

PubMed Central

1 Twice daily administration of 0.25 mg digoxin tablets (Lanoxin) or of 0.2 mg digoxin in solution in soft gelatin capsules (Lanoxicaps) produced similar mean steady state plasma digoxin concentrations in ten healthy volunteers. Respective values were 1.07 +/- 0.075 and 0.95 +/- 0.048 ng ml-1. 2 During continued administration, peak plasma concentrations occurred earlier after capsules with a tendency to higher peak levels. However, area under curve determinations over 7 h were similar. 3 Approximately 10% less digoxin was recovered in urine collected in a 12 h dosage interval during the lower dosage administration of capsules. Mean percentage urinary recovery of administered dose was 57% for tablets and 65% for capsules. 4 The enhanced bioavailability of Lanoxicaps was associated with reduced between-subject variability in plasma concentration. 5 Lanoxicaps (0.2 mg) should be approximately equivalent in effect to digoxin tablets (0.25 mg) currently available in the United Kingdom, though improved consistency would be anticipated. PMID:861135

Johnson, B F; Smith, G; French, J



Adverse effects of iron supplementation: a comparative trial of a wax-matrix iron preparation and conventional ferrous sulfate tablets.  


The acceptability of supplemental iron delivered from a wax-matrix tablet of ferrous sulfate was compared with that of a conventional ferrous sulfate tablet in a single-blind, parallel-group study. Both tablets were formulated to deliver 50 mg of elemental iron. The incidence of adverse effects was found to be significantly greater among 272 subjects taking the conventional tablets than among 271 subjects taking the wax-matrix preparation. Eighty-one percent of the subjects taking the wax-matrix preparation experienced no severe or moderate side effects as compared with only 50% of those taking the conventional tablets. PMID:4053146

Brock, C; Curry, H; Hanna, C; Knipfer, M; Taylor, L



In vitro and in vivo sustained-release characteristics of theophylline matrix tablets and novel cluster tablets.  


We compared the in vitro/in vivo properties of theophylline between two sustained-release preparations, which are administered once a day. Tablet A is a swelling/disintegration-type matrix tablet consisting of hydrophobic wax granules and hydrophilic polymer granules (cluster tablets). Tablet B is a matrix tablet consisting of hydrophilic polymer granules. We conducted a dissolution test with JPXIV in vitro, and compared the results between the two preparations. Neither pH nor agitation intensity influenced these preparations. After they were immersed in oleic acid, there were no marked changes in the dissolution properties in the dissolution test. After administration of Tablets A and B containing theophylline at 200mg to fasted dogs, we compared plasma level profiles of theophylline. The mean plasma level of theophylline gradually increased to a maximum (7.17microg/mL) 4h after administration of Tablet A. After administration of Tablet B, a similar finding was noted, with a maximum of 6.09microg/mL. Tablet B showed a higher coefficient of variation (CV) for the plasma level at each point. Subsequently, we administered two tablets of preparations A and B containing theophylline at 200mg to healthy volunteers who had not been fasted, and compared plasma level concentration of theophylline. The mean plasma level of theophylline gradually increased to a maximum (6.09microg/mL) 12h after administration of Tablet A, but then decreased, with a half-life of 9.10h. After administration of Tablet B, a similar finding was noted, with a maximum of 7.87microg/mL and a half-life of 7.76h. Tablet A showed a significantly higher plasma concentration 1 and 2h after administration; however, there were no significant differences at other points. The C(max) of Tablet B was significantly higher than that of Tablet A. However, there were no significant differences in other pharmacokinetic parameters between the two preparations. The T(max) of Tablet A was 10-12h after administration, relatively constant. However, that of Tablet B was 10-18h after administration. The CV for T(max) was 9.8% for Tablet A and 22.0% for Tablet B. After administration of Tablet B, the plasma level of theophylline varied at each point. Based on these results, inter-subject variations after administration of Tablet A may be less marked than those after administration of Tablet B. It is concluded that, the cluster tablets A developed in this study showed significantly less inter-subject variation of theophylline plasma levels than the conventional matrix tablets B. PMID:17512147

Hayashi, Tetsuo; Kanbe, Hideyoshi; Okada, Minoru; Kawase, Ichiro; Ikeda, Yasuo; Onuki, Yoichi; Kaneko, Tetsuo; Sonobe, Takashi



Comparative study of shape, course, and disintegration of the rostral notochord in some vertebrates, especially humans  

Microsoft Academic Search

The rostral part of the notochord reveals many pecularities compared with the trunk mesoderm. Furthermore, its role in head\\u000a formation and inductive processes in the head is not as well understood as the interaction of the trunk notochord with the\\u000a spinal cord and somites. To interpret experimental and molecular biological examinations in the developing head region, exact\\u000a knowledge about morphological

Klaus Barteczko; Monika Jacob



Comparative bioavailability study of two tablet formulations of digoxin.  


This investigation was carried out to evaluate the bioavailability of the generic product of digoxin 0.25 mg (cardixin) relative to a reference product, lanoxin (0.25 mg) tablets. The two formulations were found to be similar in in vitro assay (dissolution) as stipulated by USP XXIII. The comparison is carried out on 12 healthy male volunteers, who received a single dose (0.25 mg) of cardixin (product A) lanoxin (product B) as a reference product orally in the fasting state, in a randomized balanced two-way crossover design. After dosing, serial blood samples were collected for a period of 12 hr. Plasma samples were analyzed for digoxin by a sensitive and validated enzyme immunoassay method (ELISA). The maximum plasma concentration curve, up to the last measurable concentration (AUC(0-24)), was analyzed under the assumption of a multiplicative model. The time to maximum concentration (Tmax) was analyzed, assuming an additive model. The parametric confidence intervals (90%) of the mean values of the pharmacokinetic characteristics (AUC(0-12) and Cmax) for A:B ratio were, in each case, well within the bioequivalence acceptable range of 80-125%. PMID:15162916

Aboul-Enein, Hassan Y; Abou-Basha, Laila I; Wahman, Lobna F



Formulation and evaluation of metformin oro-dispersible tablets.  


The purpose of this research was to develop oro-dispersible tablets of metformin by direct compression method using super disintegrants approach, effervescent approach and sublimation approach. Powder blend was evaluated for angle of repose, bulk density, tapped density, compressibility index, Hausner's ratio and bulkiness. The tablets were evaluated for uniformity of weight, friability test, hardness, drug content, wetting time, water absorption ratio, disintegration time and in vitro dissolution. Higher dissolution rates were achieved in selected batches (A5, B4, C4, and D3) as compared to marketed product. Batch C4 prepared by effervescent approach was found to have the least disintegration time and maximum in vitro dissolution profile. PMID:21928717

Kamboj, Munish; Goyal, Surinder; Rakha, Pankaj; Arora, Gitika; Dureja, Harish; Nagpal, Manju



Diclofenac sodium multisource prolonged release tablets—a comparative study on the dissolution profiles  

Microsoft Academic Search

The aim of this work was to compare the dissolution behaviour of six diclofenac sodium prolonged release tablets of different brands obtained from the national market. The formulations contain the same amount of drug substance but different types and\\/or amount of excipients. The influence of these differences in formulation on the release characteristics of the dosage forms was evaluated on

Paola Bertocchi; Eleonora Antoniella; Luisa Valvo; Stefano Alimonti; Adriana Memoli



Comparative bioavailability of alpha-methyldopa normal and film tablet formulations after single oral administration in healthy volunteers  

Microsoft Academic Search

Summary  In a single dose, randomized, cross-over study, with one week of wash-out period, the relative bioavailability of Dopegyt®\\u000a tablets containing 250 mg alpha-methyldopa (AMD) and Presinol® film tablets with identical active ingredient content was examined\\u000a in 24 healthy volunteers.\\u000a \\u000a \\u000a Since technologically two completely different preparations (a film-tablet and a non-film-tablet) having significantly different\\u000a in vitro dissolution were to be compared,

K. Róna; K. Ary; G. Renczes; B. Gachályi; Gy. Grézal; S. Drabant; I. Klebovich



Efficacy of oral powder compared with chewable tablets for lanthanum carbonate administration in hemodialysis patients.  


Lanthanum carbonate (LC) has been administered in a chewable tablet form for patients with hyperphosphatemia undergoing dialysis. However, some patients have difficulty chewing the tablets. LC oral powder has recently been released in Japan. The purpose of this study was to clarify the efficacy of LC oral powder form compared with that of chewable tablet form. The efficacy and safety of LC oral powder was retrospectively assessed in hemodialysis patients who switched from chewable tablet form to oral powder form without dose modification. Thirty-six patients (mean age, 66.8 ± 10.5 years; male, 64%; 39% with diabetes; mean duration of dialysis treatment, 99.2 ± 95.6 months) were enrolled in this study between June and July of 2012. Changes in clinical data and adverse events after the switch to oral powder form were investigated. The average dose of LC was 1180 ± 520 mg/day. Serum phosphorus levels were significantly decreased after the switch from chewable tablet form to oral powder form (5.3 ± 1.7 mg/dL at baseline vs. 4.9 ± 1.2 mg/dL at after 1 month after, P = 0.038). In contrast, no significant differences were observed in serum calcium and parathyroid hormone levels. Furthermore, no significant differences were evident in weight gain after the switch to oral powder form (2.5 ± 1.2 kg at baseline vs. 2.4 ± 1.1 kg at 1 month after the switch, P = 0.29). No serious adverse events were recorded. Our results suggest that LC is more effective in oral powder form than chewable tablet form for hemodialysis patients. PMID:24134326

Sakurada, Tsutomu; Oishi, Daisuke; Shibagaki, Yugo; Yasuda, Takashi; Kimura, Kenjiro



Comparative release profile of sustained release matrix tablets of verapamil HCl  

PubMed Central

Introduction: Verapamil hydrochloride (VH) is a calcium channel blocking agent used in the treatment of hypertension, cardiac arrhythmia and angina pectoris. The short half-life and high frequency of administration of VH makes it a suitable candidate for designing sustained drug delivery system. The aim of the present investigation was to develop a sustained release matrix tablet of verapamil hydrochloride (VH) using ethyl cellulose, methyl cellulose, Eudragit RS 100, hydroxypropyl methylcellulose and carboxymethyl cellulose and to evaluate the drug release kinetics. Materials and Methods: In order to achieve the required sustained release profile, the tablets were prepared by a wet granulation method using avicel PH 101 and magnesium stearate as binder and lubricant, respectively. Results: The formulated tablets were characterized for pre-compression and post-compression parameters and they were in the acceptable limits. The drug release data obtained after an in vitro dissolution study was fitted to various release kinetic models in order to evaluate the release mechanism and kinetics. The criterion for selecting the best fit model was linearity (coefficient of correlation). Drug release mechanism was found to follow a complex mixture of diffusion, swelling and erosion. Furthermore, to minimize the initial burst drug release, batches were coated by using Eudragit RS100 polymer. After coating the tablets, a better release profile of the formulated tablets was expected and the release rate of the drug was compared with the marketed SR tablet of VH. Conclusion: The dosage form holds the potential to control the release rate of drug and extend the duration of action of a drug. PMID:23799207

Mathur, Vikas; Nagpal, Kalpana; Singh, Shailendra Kumar; Mishra, Dina Nath



Towards a real time release approach for manufacturing tablets using NIR spectroscopy.  


The aim of this study was to use the near-infrared spectroscopy (NIRS) as a process analytical tool to evaluate the conformity of paracetamol tablets in terms of four Pharmacopoeia tests (content uniformity, hardness, disintegration time, friability) and to control in-line blend uniformity. Tablets were manufactured by direct compression. Three different active pharmaceutical ingredient (API) concentrations were manufactured and three different compaction pressures were used. Intact tablets were analysed by transmission mode with NIRS prior to European Pharmacopoeia tests that were used as reference methods. Partial least square (PLS) regression was selected to build the prediction NIR models for content uniformity, tablet hardness and disintegration time. The prediction of NIR content uniformity and tablet hardness methods were validated using the accuracy profile approach. The values of the root mean squared error of calibration (RMSEC) and the root mean squared error of prediction (RMSEP) for the disintegration time indicated the robustness and the global accuracy of the NIR model. Regarding the tablet friability test, the classification was based on K-nearest neighbours (KNN). Then tablet NIR analyses successfully allowed the prediction of their conformity. Compared to the time consuming Pharmacopoeia reference methods, the benefit of this nondestructive method is significant, especially for reducing batch release time. PMID:24880992

Pestieau, Aude; Krier, Fabrice; Thoorens, Grégory; Dupont, Anaïs; Chavez, Pierre-François; Ziemons, Eric; Hubert, Philippe; Evrard, Brigitte



Microwave assisted synthesis and evaluation of modified pea starch as tablet superdisintegrant.  


In the present study, cross linked sodium carboxymethylated pea starch (SCPS) was synthesized and evaluated as tablet superdisintegrant in diclofenac sodium based tablets. SCPS was synthesized using native pea starch with monochloroacetic acid and NaOH in microwave radiation environment. Finally the dried product was cross-linked with phosphorous oxychloride, which produced granular highly swellable starch. SCPS with degree of substitution of 0.34 was formed and it was further evaluated as superdisintegrant in diclofenac sodium based tablets. Diclofenac sodium tablets were prepared by direct compression method with 2, 4, 6 and 8%w/w of SCPS as superdisintegrant and further comparatively evaluated for in vitro disintegration and dissolution study with Sodium starch glycolate containing tablets as reference. The results revealed that SCPS could be a promising superdisintegrant for immediate release tablets in concentration dependant manner. PMID:21235480

Singh, Akhilesh V; Singh, Anudwipa; Nath, Lila K



A comparative study of compaction properties of binary and bilayer tablets  

Microsoft Academic Search

Bi-layer tablets have been developed to achieve controlled delivery of different drugs with pre-defined release profiles. However, the production of such tablets has been facing great difficulties as the layered tablets are prone to fracture. In this paper, the compaction behaviour of binary mixtures and bilayer tablets of two common pharmaceutical excipients, Microcrystalline cellulose and lactose, is investigated. The effects

Chuan-Yu Wu; Jonathan P. K. Seville



Comprehensive review on oral disintegrating films.  


Fast-dissolving drug-delivery systems were first developed in the late 1970s as an alternative to tablets, capsules, and syrups for pediatric and geriatric patients who experience difficulties swallowing traditional oral solid dosage forms. In response to this need, a variety of orally disintegrating tablet (ODT) formats were commercialized, which disintegrate within 1 min when placed in the mouth without drinking water or chewing. Oral drug delivery technology has improved from conventional dosage forms to modified release dosage forms to ODT to the recent oral disintegrating films (ODF). Oral disintegrating film or strip that employs a water dissolving polymer which allows the dosage form to quickly hydrate by saliva, adhere to mucosa, and disintegrate within a few seconds, dissolve and releases medication for oromucosal absorption when placed on the tongue or oral cavity. Oral strip technology provides an alternate route for drugs with first pass metabolism. This review give details of materials used in ODF, manufacturing aspects, technologies, evaluation tests and marketed products. PMID:22920576

Nagaraju, T; Gowthami, R; Rajashekar, M; Sandeep, S; Mallesham, M; Sathish, D; Kumar, Y Shravan



Comparative in vitro and in vivo evaluation of three tablet formulations of amiodarone in healthy subjects  

PubMed Central

Background and the purpose of the study The relative in vivo bioavailability and in vitro dissolution studies of three chemically equivalent amiodarone generic products in healthy volunteers was evaluated in three separate occasions. The possibility of a correlation between in vitro and in vivo performances of these tablet formulations was also evaluated. Methods The bioequivalence studies were conducted based on a single dose, two-sequence, cross over randomized design. The bioavailability was compared using AUC0–72, AUC0–8, Cmax and Tmax. Similarity factor, dissolution efficiency (DE), and mean dissolution time (MDT) was used to compare the dissolution profiles. Polynomial linear correlation models were tested using either MDT vs mean residence time (MRT) or fraction of the drug dissolved (FRD) vs fraction of the drug absorbed (FRA). Results Significant differences were found in the dissolution performances of the tested formulations and therefore they were included in the development of the correlation. The 90% confidence intervals of the log-transformed AUC0-72, AUC0–8, and Cmax of each two formulations in each bioequivalence studies were within the acceptable range of 80–125%. Differences were not observed between the untransformed Tmax values. Poor correlation was found between MRT and MDT of the products. A point-to-point correlation which is essential for a reliable correlation was not obtained between pooled FRD and FRA. The dissolution condition which was used for amiodarone tablets failed for formulations which were bioequivalent in vivo and significant difference between the dissolution characteristics of products (f2<50) did not reflect their in vivo properties. Major conclusions Bioequivalence studies should be considered as the only acceptable way to ensure the interchangeability and in vivo equivalence of amiodarone generic drug products. The dissolution conditions used of the present study could be used for routine and in-process quality control of amiodarone tablet formulations. PMID:22615617



Childhood disintegrative disorder  


... had already learned The condition is similar to autistic disorder ( autism ). ... such as childhood schizophrenia or pervasive developmental disorder (autism). The most important sign of childhood disintegrative disorder ...


In vitro--in vivo evaluation of tableted caseinchitosan microspheres containing diltiazem hydrochloride.  


Casein-chitosan microspheres containing diltiazem hydrochloride (DTZ.HCL) were prepared using aqueous coacervation technique. The formed microspheres were not suitable for tableting by direct compression due to their poor binding properties. The effect of hydroxypropylmethylcellulose (HPMC), ethylcellulose (EC), carbopol 940 and egg albumin as dry binders at different concentrations on the properties of the tablets was studied. Each blend of microspheres with dry binder and 2% w/w magnesium stearate as glidant was hand-filled into the die cavity of a single punch tablet machine to ensure constant amount of drug (90 mg) in each tablet. The compression force was adjusted to produce tablets with hardness value about 7.73 +/- 0.79 Kp. The prepared tablets showed good appearance and low friability. The tested binders HPMC (10 and 30% w/w) and EC (20 and 30% w/w) gave fast tablet disintegration with high initial drug release (burst effect) while, carbopol 940 (5 and 10% w/w) and egg albumin (30% w/w) gave non-disintegrating tablets with low initial drug release. Tableted microspheres prepared with 30% egg albumin showed drug release profile similar to one of the commercial tablets (Dilzem retard, 90 mg) and was chosen for in-vivo study. Tableted microspheres and commercial tablets were administered orally in different occasions to six beagle dogs and diltiazem was assayed in dog plasma. The pharmacokinetic parameters including maximum drug concentration (Cmax) and time to reach that maximum (Tmax) were 106.24 +/- 17.96 and 5.8 +/- 2.04 hours, respectively, for the commercial sustained release DTZ tablets while, those were 107.9 +/- 12.89 and 3.6 +/- 1.36 hours, respectively for tableted microspheres. The elimination half-lives were nearly the same for the commercial and the formulated tablets (8.22 +/- 4.19 and 7.95 +/- 4.28 hours, respectively). No statistical differences (P > 0.05) were found between the two treatments for area under the plasma concentration curve (AUC0 infinity), mean residence time (MRT) and rate of drug absorption (Cmax/AUC0 infinity) indicating comparable extent and rate of drug absorption for both formulations. It was concluded that the formulated tableted microspheres provide an acceptable delivery for DTZ over an extended period of time. PMID:12680034

al-Suwayeh, Saleh A; el-Helw, Abdel-Rehim M; al-Mesned, Abdullah F; Bayomi, Mohsen A; el-Gorashi, Abobakr S



Formulation and Characterization of Oral Mucoadhesive Chlorhexidine Tablets Using Cordia myxa Mucilage  

PubMed Central

Background The dilution and rapid elimination of topically applied drugs due to the flushing action of saliva is a major difficulty in the effort to eradicate infections of oral cavity. Utilization a proper delivery system for incorporation of drugs has a major impact on drug delivery and such a system should be formulated for prolonged drug retention in oral cavity. Objectives The aim of the present study was the use of mucilage of Cordia myxa as a mucoadhesive material in production of chlorhexidine buccal tablets and its substitution for synthetic polymers such as HPMC. Materials and Methods The influence of mucilage concentration on the physicochemical responses (hardness, friability, disintegration time, dissolution, swelling, and muco-adhesiveness strength) was studied and swelling of mucilage and HPMC were compared. The evaluated responses included pharmacopoeial characteristics of tablets, the force needed to separate tablets from mucosa, and the amount of water absorbed by tablets. Results In comparison to HPMC, the rise of mucilage concentration in the formulations increased disintegration time, drug dissolution rate, and reduced MDT. Also, compared to 30% HPMC, muco-adhesiveness strength of buccal tablets containing 20% mucilage was significantly higher. Conclusions It can be concluded that the presence of Cordia myxa powdered mucilage may significantly affect the tablet characteristics, and increasing in muco-adhesiveness may be achieved by using 20% w/w mucilage. PMID:24624170

Moghimipour, Eskandar; Aghel, Nasrin; Adelpour, Akram



Comparative bioavailability of alpha-methyldopa normal and film tablet formulations after single oral administration in healthy volunteers.  


In a single dose, randomized, cross-over study, with one week of wash-out period, the relative bioavailability of Dopegyt tablets containing 250 mg alpha-methyldopa (AMD) and Presinol film tablets with identical active ingredient content was examined in 24 healthy volunteers. Since technologically two completely different preparations (a film-tablet and a non-film-tablet) having significantly different in vitro dissolution were to be compared, both preparations were compared to a third one, AMD solution (Dopegyt solution) with 250 mg/50 ml concentration. Plasma concentrations of the drug were measured for 24 hours post-dose, applying HPLC with fluorometric detection. Pharmacokinetic parameters calculated from individual data (AUC0-infinity, AUC0-t, Cmax, Cmax/AUC0-infinity, t(max)) were evaluated statistically. Wilcoxon's nonparametric test and the four-way variance analysis could not detect any significant difference at the usual a=95% probability level in these pharmacokinetic parameters of the two tablet preparations. For AUC0-infinity at the 90% probability level, the confidence interval was 0.883-1.237 (with an estimated geometric mean of 1.045), for the test/reference ratio of Dopegyt and Presinol tablets, thus the two preparations proved to be bioequivalent. The relative bioavailability of Dopegyt (test preparation) and Presinol (reference preparation) calculated from the AUC0-infinity values was 116.7+/-56.7% that also confirmed bioequivalence. The results of all the applied statistical tests suggest that Dopegyt and Presinol can be considered as bioequivalent preparations. PMID:11554430

Róna, K; Ary, K; Renczes, G; Gachályi, B; Grézal, G Y; Drabant, S; Klebovich, I



Formulation and In Vitro Evaluation of Ofloxacin Tablets using Natural Gums as Binders.  


Natural gums are economical, easily available, and useful as tablet binders. In the present investigation, an attempt was made to formulate Ofloxacin tablets using three natural binders, namely Acacia arabica, Hibiscus esculentus, and xanthan gum. Such six batches of Ofloxacin tablets were prepared by using different types and amounts of the natural binders by the wet granulation method. The tablets were analyzed for their hardness, friability, and weight variation, and in vitro release was performed in a phosphate buffer at pH 6.8. The prepared tablets were also evaluated for their various release kinetics and similarity factors f2. The physical properties of the tablets containing the natural binders showed sufficient hardness, desirable disintegration time, and low friability. Their better percentage of drug release was observed as compared to the marketed formulation showing more than 85% drug release within 45 minutes. The in vitro release data was well-fitted into zero-order and the values of release exponent 'n' were between 0.303 and 0.514. The high similarity factor f2 of 64.50 was achieved with the best batch in comparison to the marketed tablets. The results obtained indicated that the gum Acacia arabica performed as well as gelatin compared to the other binders for the Ofloxacin tablet formulation. PMID:24959411

Mistry, Amisha K; Nagda, Chirag D; Nagda, Dhruti C; Dixit, Bharat C; Dixit, Ritu B



Efficacy and safety of sodium phosphate tablets compared with PEG solution in colon cleansing: Two identically designed, randomized, controlled, parallel group, multicenter phase III trials  

Microsoft Academic Search

Background: Liquid purgatives for cleansing before colonoscopy often are poorly tolerated. A sodium phosphate tablet has been developed to provide equivalent efficacy with better patient tolerance. These 2 studies compare the safety, efficacy, and patient acceptance of the tablet (Visicol) to a polyethylene glycol (PEG) solution in adults undergoing colonoscopy. Methods: Two identically designed, randomized, investigator-blinded, multicenter trials were performed.

David Kastenberg; Richard Chasen; Cuckoo Choudhary; Dennis Riff; Stephen Steinberg; Eric Weiss; Lawrence Wruble



Development and evaluation of controlled-release diclofenac microspheres and tabletted microspheres.  


Diclofenac wax microspheres were prepared using the congealable dispersephase encapsulation method. Emulsifiers, glyceryl monostearate (GMS) and stearic acid, were added to improve the efficiency of emulsification. Microspheres containing either of the emulsifiers or both showed a high drug content (80-90%) and the particle size distribution was log-normal compared with microspheres without the emulsifiers. Increase in GMS concentration decreased the drug release and, in contrast, stearic acid appeared to channel the drug from the wax matrix. The addition of both emulsifiers at different concentrations modified drug release. Increase in dispersant (PVP) concentration, and decrease in microsphere size accelerated the rate of drug release. Higuchi/Baker Londsdale spherical matrix dissolution kinetics was followed. Disintegrating tableted microspheres were prepared with Avicel and Explotab. With the increase in compression pressure the crushing force and disintegrating time increased, but the thickness decreased, and the dissolution profile did not appear to be affected. Slightly faster release was noticed with tableted microspheres compared with that of uncompressed microspheres. Tablets containing 40 and 60% microsphere loadings had disintegration times of 5.12 +/- 0.63 and 57.73 +/- 3.53 min, respectively. In contrast, tablet formulation containing 80% microsphere load had a significant increase in disintegration time (130.83 +/- 4.26 min). The dissolution from this formulation also showed a lag time of 30 min in contrast with the other two formulations, which showed no lag time. Increased microsphere size from 215 to 630 microns had no effect on tableting properties (such as hardness and thickness); and only very little effect on dissolution. The microspheres appeared deformed but intact irrespective of compression pressures on scanning electron micrographs. PMID:7931945

Vilivalam, V D; Adeyeye, C M



Desktop 3D printing of controlled release pharmaceutical bilayer tablets.  


Three dimensional (3D) printing was used as a novel medicine formulation technique for production of viable tablets capable of satisfying regulatory tests and matching the release of standard commercial tablets. Hydroxypropyl methylcellulose (HPMC 2208) (Methocel™ K100M Premium) and poly(acrylic acid) (PAA) (Carbopol(®) 974P NF) were used as a hydrophilic matrix for a sustained release (SR) layer. Hypromellose(®) (HPMC 2910) was used as a binder while microcrystalline cellulose (MCC) (Pharmacel(®) 102) and sodium starch glycolate (SSG) (Primojel(®)) were used as disintegrants for an immediate release (IR) layer. Commercial guaifenesin bi-layer tablets (GBT) were used as a model drug (Mucinex(®)) for this study. There was a favourable comparison of release of the active guaifenesin from the printed hydrophilic matrix compared with the commercially available GBT. The printed formulations were also evaluated for physical and mechanical properties such as weight variation, friability, hardness and thickness as a comparison to the commercial tablet and were within acceptable range as defined by the international standards stated in the United States Pharmacopoeia (USP). All formulations (standard tablets and 3D printed tablets) showed Korsmeyer-Peppas n values between 0.27 and 0.44 which indicates Fickian diffusion drug release through a hydrated HPMC gel layer. PMID:24280018

Khaled, Shaban A; Burley, Jonathan C; Alexander, Morgan R; Roberts, Clive J



Comparative effects of different cellulosic-based directly compressed orodispersable tablets on oral bioavailability of famotidine  

Microsoft Academic Search

Famotidine is a potent H2-receptor antagonist most commonly used by elderly patients. Orodispersible tablets (ODT) are gaining popularity over conventional tablets due to their convenience and suitability for patients having dysphagia. The purpose of this study is to prepare famotidine ODT using the economic direct-compression method.A 32 full factorial design was used to evaluate the influence of different excipients on

A. Abdelbary; A. H. Elshafeey; G. Zidan



Diclofenac sodium multisource prolonged release tablets--a comparative study on the dissolution profiles.  


The aim of this work was to compare the dissolution behaviour of six diclofenac sodium prolonged release tablets of different brands obtained from the national market. The formulations contain the same amount of drug substance but different types and/or amount of excipients. The influence of these differences in formulation on the release characteristics of the dosage forms was evaluated on the European Pharmacopoeia apparatus 2 (paddle) employing eight different dissolution media in the pH range 1.2-8. Friability and hardness were tested too according to the European Pharmacopoeia. Dissolution profiles obtained from the studied formulations showed that the release characteristics vary considerably among different manufacturers and that even identical formulations show rather dissimilar release profiles in all the studied media. Use of both SIF without pancreatin and SIF without pancreatin containing 1% (w/v) Tween 20 resulted in strong discrimination among products. A correlation between friability and hardness and in vitro dissolution was evidenced for two formulations having identical excipient composition. PMID:15797788

Bertocchi, Paola; Antoniella, Eleonora; Valvo, Luisa; Alimonti, Stefano; Memoli, Adriana



Mucoadhesive bilayer tablets of propranolol hydrochloride.  


The purpose of this research was to study mucoadhesive bilayer buccal tablets of propranolol hydrochloride using the bioadhesive polymers sodium alginate (Na-alginate) and Carbopol 934P (CP) along with ethyl cellulose as an impermeable backing layer. The tablets were evaluated for weight variation, thickness, hardness, friability, surface pH, mucoadhesive strength, swelling index, in vitro drug release, ex vivo drug permeation, ex vivo mucoadhesion, and in vivo pharmacodynamics in rabbits. Tablets containing Na-alginate and CP in the ratio of 5:1 (F2) had the maximum percentage of in vitro drug release without disintegration in 12 hours. The swelling index was proportional to Na-alginate content and inversely proportional to CP content. The surface pH of all tablets was found to be satisfactory (7.0 +/- 1.5), close to neutral pH; hence, buccal cavity irritation should not occur with these tablets. The mechanism of drug release was found to be non-Fickian diffusion and followed zero-order kinetics. The formulation F4 was optimized based on good bioadhesive strength (28.9 +/- 0.99 g) and sustained in vitro drug permeation (68.65% +/- 3.69% for 12 hours). The behavior of formulation F4 was examined in human saliva, and both the drug and the buccal tablet were found to be stable. The formulation F4 was applied to rabbit oral mucosa for in vivo studies. The formulation inhibited isoprenaline-induced tachycardia. The studies conducted in rabbits confirmed the sustained release as compared with intravenous administration. PMID:17915827

Patel, Vishnu M; Prajapati, Bhupendra G; Patel, Harsha V; Patel, Karshanbhi M



A single blind normal volunteer bioavailability study of a new microencapsulated potassium chloride tablet compared with two reference potassium formulations.  


A single blind placebo controlled, cross-over study comparing a new microencapsulated potassium chloride tablet (MET) with two reference formulations of oral potassium, potassium chloride solution (PS) and potassium chloride wax-matrix tablets (WMT), was performed in 12 normal healthy volunteers. Urinary potassium excretion was the main criterion of comparison. Results showed that all three formulations have excellent bioavailability. This indicates that potassium absorption in the stomach is similar to that in more distant portions of the gut. The slow-release characteristics of both MET and WMT were confirmed. Clinical and pharmacological tolerance was excellent and no side-effects were reported with any of the potassium formulations studied. PMID:1814742

Caplain, H; Dahan, R; Pamphile, R; Thebault, J J



[Applicability of a natural swelling matrix as the propellant of osmotic pump tablets].  


The purpose of this study is to investigate the applicability of a natural swelling matrix derived from boat-fruited sterculia seed (SMS) as the propellant of osmotic pump tablets. The sugar components, static swelling, water uptake and viscosity of SMS were determined and compared with that of polythylene oxide (WSR-N10 and WSR-303). Both ribavirin and glipizide were used as water-soluble and water-insoluble model drugs. Then, the monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide were prepared using SMS as the osmotically active substance and propellant. SMS was mainly composed of rhamnose, arabinose, xylose and galactose and exhibited relatively high swelling ability. The area of the disintegrated matrix tablet was 20.1 times as that at initial after swelling for 600 s. SMS swelled rapidly and was fully swelled (0.5%) in aqueous solution with relative low viscosity (3.66 +/- 0.03) mPa x s at 25 degrees C. The monolayer osmotic pump tablets of ribavirin and the bilayer osmotic pump tablets of glipizide using SMS as propellant exhibited typical drug release features of osmotic pumps. In conclusion, the swelling matrix derived from boat-fruited sterculia seed, with low viscosity and high swelling, is a potential propellant in the application of osmotic pump tablets. PMID:24187843

Wu, Li; Li, Hai-Yan; Yin, Xian-Zhen; Li, Ying; Chen, Jian-Xiu; Hu, Rong-feng; Zhang, Ji-Wen



Unintegration, disintegration and deintegration  

Microsoft Academic Search

This paper is a response to a review of the conference titled, ‘Unintegration, Disintegration and Integration’, written by Cathy Urwin and Maria Rhode in the ACP Bulletin. The review mentioned Michael Fordham, noting that he referred to a ‘good’ kind of unintegration. In this paper, I point out that this is a somewhat misleading reference to what he termed ‘deintegration’.

Elizabeth Urban



Comparative efficacy of soluble aspirin and aspirin tablets in postoperative dental pain  

Microsoft Academic Search

The efficacy of single doses (1.2 g) of soluble aspirin and aspirin tablets was determined in a randomised, placebo-controlled, double-blind, parallel study in 90 patients (45 females) with postoperative pain after removal of impacted lower third molars. Also investigated was the relationship between plasma aspirin esterase activity and overall pain scores after both aspirin preparations. Patients reported significantly less pain

R. A. Seymour; F. M. Williams; N. M. Luyk; M. A. Boyle; P. M. Whitfield; E. Nicholson; P. Ward Booth; M. D. Rawlins



Formulation and evaluation of bi-layer tablet of metoclopramide hydrochloride and ibuprofen.  


The aim of this study was to prepare bi-layer tablet of Metoclopramide Hydrochloride (MTH) and Ibuprofen (IB) for the effective treatment of migraine. MTH and IB were formulated as immediate and sustained release layer respectively. MTH was formulated as immediate release layer by using various disintegrants like Ac-Di-Sol, Polyplasdone XL, Explotab, Agar and Gellan Gum. Treated form of gellan gum and agar was prepared and compared for their disintegrant efficiency with other disintegrants. IB was formulated as sustained release layer using hydrophilic matrix (hydroxypropylmethylcellulose [HPMC K(4)M]). The effect of concentration of hydrophilic matrix (HPMC K(4)M), binder (polyvinylpyrollidone [PVP K(30)]) and buffer (sodium bicarbonate) on IB release was studied. The dissolution study of sustained release layer showed that an increasing amount of HPMC or PVP K(30) results in reduced IB release. The inclusion of buffer (sodium bicarbonate) enhanced the release of IB from sustained release layer. The rational for formulation of bi-layer tablet of these two drugs in combination was (1) MTH increases the absorption of acidic non-steroidal anti-inflammatory drug (NSAID) by increasing gastric motility. So sequential release of MTH (as immediate release) and IB (as sustained release) was suitable for treatment of migraine. (2) MTH was degraded when prolonged contact with acidic NSAID. Bi-layer tablet was suitable for preventing direct contact of these two drugs and thus to maximize the efficacy of combination of two drugs for migraine. PMID:18612830

Shiyani, Bhavesh; Gattani, Surendra; Surana, Sanjay



Investigation of the performance of the disintegration test for dietary supplements.  


The aim of this study was to investigate how beaker size, basket assembly, use of disk, and immersion medium impact the disintegration time of dietary supplements. The disintegration times were determined for five tablet and two capsule products. A two-station disintegration tester was used with Apparatus A or Apparatus B as described in the United States Pharmacopeia (USP) chapters, <701> and <2040>. Two beakers complying with the harmonized specifications were used, one with a volume of 1,000 mL and one with a 1,500-mL volume. The disintegration data were analyzed using ANOVA for the following factors: beaker size, equipment (App A and B) and condition (with/without disk). Two tablet products were not sensitive to any changes in the test conditions or equipment configurations. One product was only partially sensitive to the test conditions. The other products showed impact on the disintegration time for all test conditions. The results revealed that these tablet products might pass or fail current USP disintegration requirements depending on the equipment configuration. Similar results were obtained for the two investigated capsule formulations. One product might fail current USP disintegration requirements if the large beaker was used, but might pass the disintegration requirements when the small beaker was used. Hydroxy propyl methyl cellulose capsules were mostly influenced if sodium instead of a potassium buffer was used as the immersion medium. The results demonstrate that the current harmonized ICH specifications for the disintegration test are insufficient to make the disintegration test into reliable test for dietary supplements. PMID:20652779

Almukainzi, May; Salehi, Mahnor; Araci Bou-Chacra, Nadia; Löbenberg, Raimar



Development and Evaluation of Melt-in-Mouth Tablets of Metoclopramide Hydrochloride Using Novel Co-processed Superdisintegrants  

PubMed Central

In the present investigation, a novel multifunctional co-processed superdisintegrants consisting of crospovidone and Kyron T-314 were fabricated by solvent evaporation method to develop melt-in-mouth tablets of metoclopramide hydrochloride with a view to enhance patient compliance by direct compression method. The simple physical blends and co-processed mixture of superdisintegrants were characterized for angle of repose, bulk density, tapped density, Carr's index, Hausner's ratio and compatibility studies by FTIR spectroscopy. Melt-in-mouth tablets of metoclopramide hydrochloride were prepared using the physical blends and co-processed mixture of superdisinterants and were evaluated for hardness, friability, in vitro disintegration time, in vitro dispersion time, wetting time, water absorption ratio, drug content, in vitro drug release and accelerated stability study at 40±2° temperature and 75±5% relative humidity. Among the tablets evaluated, formulation F-X prepared by adding co-processed superdisintegrants in ratio of 1:1 showed minimum in vitro dispersion time of 9.71±0.021 s, in vitro disintegration time of 5.70±0.117 s and higher amount of drug release of 99.695±0.29% at the end of 1 min. Formulation F-X was emerged as the overall best formulation based on drug release characteristics in pH 6.8 phosphate buffer compared with the tablets obtained from conventional method of manufacture as well as with marketed preparation. Analysis of drug release data indicated that formulation F-X followed first order kinetics. This study revealed that the co-processed mixture of superdisintegrants have excellent flow properties, high compressibility, render low disintegration time to tablets and have better binding properties as compared to physical blends of superdisintegrants. These materials can be a good substitute for inert superdisintegrants, which are normally used in tablet manufacturing.

Ladola, M. K.; Gangurde, A. B.



Comparative in vitro-in vivo correlation analysis with pioglitazone tablets  

PubMed Central

Objective To assess the in vitro-in vivo correlation of immediate release formulation of pioglitazone 30 mg film coated tablet. Methods In vitro release data were obtained for test and reference formulation using the USP paddle method (Apparatus 2) at 50 r/min and with the temperature of 37 °C in the dissolution medium of 0.1 mol/L hydrochloric acid of pH 1.2. Twelve healthy volunteers were administered both test and reference pioglitazone 30 mg tablet orally and blood samples were collected over 24 h period. In vivo drug concentrations were analyzed by a simple, fast and precise reverse phase binary HPLC method with UV detection to establish a correlation between in vitro release and in vivo absorption data. Results Similarity factor (f2) and dissimilarity factor (f1) were determined for the time intervals of 5, 10, 15, 30, 45, 60, 75, 90, 105 and 120 min and the obtained values were 65.17%, 59.37%, 63.62%, 66.61%, 68.89%, 70.73%, 72.27%, 73.59%, 74.65% and 75.67% for f2 and 9.43%, 9.00%, 5.42%, 3.86%, 3.07%, 2.56%, 2.20%, 1.94%, 1.82% and 1.65% for f1 at respective time intervals. Mean dissolution time for test and reference products were obtained at 3.06 and 3.40 min respectively. f2 and f1 values obtained were within the acceptable range f2 (50%-100%) and f1 (<15%). Conclusions Comparison of dissolution profiles corroborate that the test and reference formulations are similar and there is no linear in vitro-in vivo correlation.

Saha, Sajal Kumar; Chowdhury, A. K. Azad; Bachar, Sitesh Chandra; Das, Sreedam Chandra; Kuddus, Ruhul H.; Uddin, Md Aftab



Satellite disintegration dynamics  

NASA Technical Reports Server (NTRS)

The subject of satellite disintegration is examined in detail. Elements of the orbits of individual fragments, determined by DOD space surveillance systems, are used to accurately predict the time and place of fragmentation. Dual time independent and time dependent analyses are performed for simulated and real breakups. Methods of statistical mechanics are used to study the evolution of the fragment clouds. The fragments are treated as an ensemble of non-interacting particles. A solution of Liouville's equation is obtained which enables the spatial density to be calculated as a function of position, time and initial velocity distribution.

Dasenbrock, R. R.; Kaufman, B.; Heard, W. B.



Disintegration of liquid sheets  

NASA Technical Reports Server (NTRS)

The development, stability, and disintegration of liquid sheets issuing from a two-dimensional air-assisted nozzle is studied. Detailed measurements of mean drop size and velocity are made using a phase Doppler particle analyzer. Without air flow the liquid sheet converges toward the axis as a result of surface tension forces. With airflow a quasi-two-dimensional expanding spray is formed. The air flow causes small variations in sheet thickness to develop into major disturbances with the result that disruption starts before the formation of the main break-up region. In the two-dimensional variable geometry air-blast atomizer, it is shown that the air flow is responsible for the formation of large, ordered, and small chaotic 'cell' structures.

Mansour, Adel; Chigier, Norman



Significant improvements in self-reported gastrointestinal tolerability, quality of life, patient satisfaction, and adherence with lopinavir\\/ritonavir tablet formulation compared with soft gel capsules  

Microsoft Academic Search

BACKGROUND: The tablet formulation of ritonavir-boosted lopinavir (LPV\\/r; Kaletra®) has many advantages over the soft gel capsule (SGC) formulation, including lower pill count, no refrigeration requirement, and no dietary restrictions. These advantages may help improve patient compliance and therefore increase adherence to treatment. However, there are limited data regarding patient preferences and only recently was the comparative efficacy and tolerability

Shannon Schrader; Susan K Chuck; Laurie W Rahn; Paras Parekh; Katherine G Emrich



Comparing the Therapeutic Effects of Garlic Tablet and Oral Metronidazole on Bacterial Vaginosis: A Randomized Controlled Clinical Trial  

PubMed Central

Background: Bacterial vaginosis (BV) is one of the most common gynecological infections during reproductive age. Although metronidazole is one of the most effective medications recommended as the first-line treatment, it has various side effects. Because of the side effects and contraindications of some chemical medicines, using herbs has been investigated in treating BV. Objectives: The aim of this study was to compare the effect of garlic tablet (Garsin) and oral metronidazole in clinical treatment of the BV in women referred to Resalat Health Center, affiliated with Mazandaran University of Medical Sciences, in 2013. Patients and Methods: This randomized clinical trial was conducted on 120 married women aged 18 to 44 years who were diagnosed with BV by Amsel’s clinical criteria and Gram staining. Enrolled women were randomly allocated to two groups of 60 patients and were treated with either garlic tablet or oral metronidazole for seven days. Amsel’s criteria and Gram stain were assessed seven to ten days after beginning the treatment period and side effects were registered. Results: Amsel’s criteria were significantly decreased after treatment with garlic or metronidazole (70% and 48.3%, respectively; P < 0.001). Therapeutic effects of garlic on BV were similar to that of metronidazole (63.3% and 48.3%, respectively; P = 0.141). There were significant differences between the two treatment groups in terms of side effects; metronidazole was associated with more complications (P = 0.032). Conclusions: This study reveals that garlic could be a suitable alternative for metronidazole in treatment of BV in those interested in herbal medicines or those affected by side effects of metronidazole. PMID:25237588

Mohammadzadeh, Farnaz; Dolatian, Mahrokh; Jorjani, Masoome; Alavi Majd, Hamid; Borumandnia, Nasrin



Mechanistic understanding of food effects: water diffusivity in gastrointestinal tract is an important parameter for the prediction of disintegration of solid oral dosage forms.  


Much interest has been expressed in this work on the role of water diffusivity in the release media as a new parameter for predicting drug release. NMR was used to measure water diffusivity in different media varying in their osmolality and viscosity. Water self-diffusion coefficients in sucrose, sodium chloride, and polymeric hydroxypropyl methylcellulose (HPMC) solutions were correlated with water uptake, disintegration, and drug release rates from trospium chloride immediate release tablets. The water diffusivity in sucrose solutions was significantly reduced compared to polymeric HPMC and molecular sodium chloride solutions. Water diffusivity was found to be a function of sucrose concentration in the media. Dosage form disintegration and drug release was to be affected by water diffusivity in these systems. This observation can be explained by hydrogen bonding formation between sugar molecules, an effect which was not expressed in sodium chloride solutions of equal osmolality. Water diffusivity and not media osmolality in general need to be considered to predict the effect of disintegration and dissolution media on drug release. Understanding the relevance of water diffusivity for disintegration and dissolution will lead to better parametrization of dosage form behavior in gastrointestinal (GI) aqueous and semisolid media. PMID:23600970

Radwan, Asma; Ebert, Sandro; Amar, Andrea; Münnemann, Kerstin; Wagner, Manfred; Amidon, Gordon L; Langguth, Peter



Lallemantia reylenne seeds as superdisintegrant: Formulation and evaluation of nimesulide orodispersible tablets  

PubMed Central

Aim: Orodispersible tablets also known as fast dissolving tablets disintegrate instantaneously within the mouth and thus can be consumed without water. The present study was aimed to formulate orodispersible tablets of nimesulide by using Lallemantia reylenne seeds as natural superdisintegrant. Materials and Methods: Powdered lallemantia seeds were characterized for powder flow properties (bulk density, tapped density, carr's consolidation index, hausner ratio, angle of repose), swelling index, viscosity, pH, and loss on drying. The prepared tablets were evaluated for different tablet parametric tests, wetting time, water absorption ratio, effective pore radius, porosity, packing fraction, in vitro and in vivo disintegration time, in vitro dissolution and stability studies. Results and Discussion: Increase in Lallementia reylenne concentration had an appreciable effect on tablet hardness and friability which clearly indicated binding potential of the seeds. Water absorption ratio increased with increase in Lallemantia reylenne concentration from batch A1 to A4. Water uptake coupled natural polymer swelling could be the most probable mechanism for concentration dependent reduction in disintegration time by the Lallemantia reylenne seeds. Porosity of the formulated tablets was found to increase from batch A1-A4. The in vitro disintegration results were in line with in vivo disintegration results. Conclusion: It could be concluded that Lallemantia reylenne seeds could be used as natural superdisintegrant in the formulation of orodispersible tablets. PMID:23071942

Malik, Karan; Arora, Gurpreet; Singh, Inderbir; Arora, Sandeep



Dissolution profile of 24 levofloxacin (100 mg) tablets.  


Although there are 23 generic levofloxacin (100 mg) tablets (LVFX tablets) and 1 brand name LVFX tablet (supply now discontinued) in Japan, there have been no reports that have evaluated and compared the dissolution profiles of LVFX tablets using the same dissolution method. We studied the dissolution profile of LVFX tablets by the Paddle method, a standard dissolution test method. Among 23 generic LVFX tablets, 2 LVFX tablets had lower dissolution rates and 14 had higher dissolution rates than the brand name LVFX tablet. It is suggested that LVFX tablets have different dissolution profiles, which could cause different pharmacokinetic profiles. PMID:23380968

Maezawa, Kayoko; Yajima, Ryo; Terajima, Tomoko; Kizu, Junko; Hori, Seiji



Comparative Study of Propranolol hydrochloride Release from Matrix Tablets with Kollidon®SR or Hydroxy Propyl Methyl Cellulose  

Microsoft Academic Search

The release of propranolol hydrochloride from matrix tablets with hydroxy propyl methyl cellulose (HPMC K15M) or Kollidon®SR\\u000a at different concentrations was investigated with a view to developing twice daily sustained release dosage form. A hydrophilic\\u000a matrix-based tablet using different concentrations of HPMC K15M or Kollidon®SR was developed using direct compression technique\\u000a to contain 80 mg of propranolol hydrochloride. The resulting matrix

J. Sahoo; P. N. Murthy; S. Biswal; S. K. Sahoo; A. K. Mahapatra



ColoPulse tablets perform comparably in healthy volunteers and Crohn's patients and show no influence of food and time of food intake on bioavailability.  


ColoPulse tablets are an innovative development in the field of oral drug delivery and are characterized by a colon-specific release. Until now ColoPulse dosage forms (only capsules) have been studied in healthy volunteers having a standardized breakfast three hours after administration but not in specific patient groups and not with a shorter interval between administration and breakfast. Information on bioavailability and release characteristics of ColoPulse tablets in Crohn's patients and the influence of food and time of food intake is a prerequisite to properly design future clinical studies with active substances in these patients. In the current cross-over study bioavailability and drug release characteristics of ColoPulse tablets were compared in healthy volunteers and in Crohn's patients in remission. Furthermore the influence of food and time of food intake on the in vivo drug release behavior of ColoPulse tablets was investigated. In this study the dual label isotope strategy was used which means that a ColoPulse tablet containing (13)C-urea and an uncoated, immediate release tablet containing (15)N2-urea were taken simultaneously. Breath and urine samples were collected during the test day for isotope analysis. The appearance of the stable isotopes in breath and/or urine provides information on the site of release from the dosage form, release characteristics and bioavailability. Both tablets were administered on two different days in a cross-over design: the first day with a breakfast (non-standardized) one hour after administration and the second day with a standardized breakfast three hours after administration of the tablets. There was no difference in instructions for administration between both days. Results of 16 healthy volunteers and 14 Crohn's patients were evaluated. At least 86% (51 out of 59) of all ColoPulse tablets administered in this study released their contents at the desired intestinal region. There was no significant difference in bioavailability between healthy volunteers and Crohn's patients on both days (day 1 75.8% vs 90.2%, p=0.070 and day 2 83.4% vs 91.4%, p=0.265). There was also no significant influence of food and time of food intake on bioavailability in healthy volunteers (75.8% and 83.4%, p=0.077) and in Crohn's patients (90.2% and 91.4%, p=0.618) when day 1 and day 2 were compared. Release characteristics did not significantly differ between healthy volunteers and Crohn's patients. However, food and time of food intake had some, clinically non-relevant, influence on the release characteristics within both groups which is in line with the fact that food affects gastro-intestinal transit times. This study shows that ColoPulse tablets enable the site-specific delivery of drugs or other compounds (e.g. diagnostics) deep in the ileo-colonic region of the intestine of Crohn's patients in a comparable amount and rate as in healthy volunteers. Food and time of food intake had no relevant influence on bioavailability. In conclusion ColoPulse delivery systems are promising and deserve further research for local therapy with immunosuppressive drugs in Crohn's patients in the near future. PMID:24096020

Maurer, J M; Schellekens, R C A; van Rieke, H M; Stellaard, F; Wutzke, K D; Buurman, D J; Dijkstra, G; Woerdenbag, H J; Frijlink, H W; Kosterink, J G W



In vitro determination of aceclofenac Mouth Dissolving Tablets.  


In the present study, Mouth Dissolving Tablets (MDTs) of aceclofenac were formulated by direct compression technique. Sodium starch glycolate and crospovidone were employed as superdisintegrants in various concentrations like 2%, 3% and 4% w/w. All prepared tablets were evaluated for weight variation, hardness, drug content, friability, disintegration time, in vitro wetting time and percent drug release. MDTs containing 4% w/w concentration of crospovidone give best results and is therefore considered as the best formula. It has shown 30 s disintegration time, 25 s wetting time and 79.34% in vitro release of drug in 25 min. PMID:24596037

Shobhit, Shobhit; Gupta, Satish Kumar



Comparative in vitro and in vivo evaluation of matrix, osmotic matrix, and osmotic pump tablets for controlled delivery of diclofenac sodium  

Microsoft Academic Search

The aim of this investigation was preparation and comparative evaluation of fabricated matrix (FM), osmotic matrix (OM), and\\u000a osmotic pump (OP) tablets for controlled delivery of diclofenac sodium (DS). All formulations were evaluated for various physical\\u000a parameters, and in vitro studies were performed on USP 24 dissolution apparatus II in pH 7.4 buffer and distilled water. In\\u000a vivo studies were

Meena Rani; Brahmeshwar Mishra



Comparative Effectiveness of Di'ao Xin Xue Kang Capsule and Compound Danshen Tablet in Patients With Symptomatic Chronic Stable Angina.  


A high proportion of patients with stable angina remains symptomatic despite multiple treatment options. Di'ao Xinxuekang (XXK) capsule and Compound Danshen (CDS) tablet have been approved for treating angina pectoris for more than 20 years in China. We compare the anti-anginal effectiveness of XXK capsule and CDS tablet in patients with symptomatic chronic stable angina. A randomized, multicenter, double-blind, parallel-group, superiority trial was conducted in 4 study sites. 733 patients with symptomatic chronic stable angina were included in the full analysis set. The primary outcomes were the proportion of patients who were angina-free and the proportion of patients with normal electrocardiogram (ECG) recordings during 20 weeks treatment. Compared with CDS, XXK significantly increased the proportion of angina-free patients, but no significant difference was noted in the proportion of patients with normal ECG recordings. Weekly angina frequency and nitroglycerin use were significantly reduced with XXK versus CDS at week 20. Moreover, XXK also improved the quality of life of angina patients as measured by the SAQ score and Xueyu Zheng (a type of TCM syndrome) score. We demonstrate that XXK capsule is more effective for attenuating anginal symptoms and improving quality of life in patients with symptomatic chronic stable angina, compared with CDS tablet. PMID:25394847

Yu, Yanan; Hu, Siyuan; Li, Guoxin; Xue, Jie; Li, Zhuoming; Liu, Xiangling; Yang, Xiyan; Dong, Bo; Wang, Donghai; Wang, Xiaofeng; Liu, Shurong; Liu, Jun; Chen, Bingwei; Wang, Liying; Liu, Songshan; Chen, Qiguang; Shen, Chunti; Wang, Zhong; Wang, Yongyan



Comparative Effectiveness of Di'ao Xin Xue Kang Capsule and Compound Danshen Tablet in Patients With Symptomatic Chronic Stable Angina  

PubMed Central

A high proportion of patients with stable angina remains symptomatic despite multiple treatment options. Di'ao Xinxuekang (XXK) capsule and Compound Danshen (CDS) tablet have been approved for treating angina pectoris for more than 20 years in China. We compare the anti-anginal effectiveness of XXK capsule and CDS tablet in patients with symptomatic chronic stable angina. A randomized, multicenter, double-blind, parallel-group, superiority trial was conducted in 4 study sites. 733 patients with symptomatic chronic stable angina were included in the full analysis set. The primary outcomes were the proportion of patients who were angina-free and the proportion of patients with normal electrocardiogram (ECG) recordings during 20 weeks treatment. Compared with CDS, XXK significantly increased the proportion of angina-free patients, but no significant difference was noted in the proportion of patients with normal ECG recordings. Weekly angina frequency and nitroglycerin use were significantly reduced with XXK versus CDS at week 20. Moreover, XXK also improved the quality of life of angina patients as measured by the SAQ score and Xueyu Zheng (a type of TCM syndrome) score. We demonstrate that XXK capsule is more effective for attenuating anginal symptoms and improving quality of life in patients with symptomatic chronic stable angina, compared with CDS tablet. PMID:25394847

Yu, Yanan; Hu, Siyuan; Li, Guoxin; Xue, Jie; Li, Zhuoming; Liu, Xiangling; Yang, Xiyan; Dong, Bo; Wang, Donghai; Wang, Xiaofeng; Liu, Shurong; Liu, Jun; Chen, Bingwei; Wang, Liying; Liu, Songshan; Chen, Qiguang; Shen, Chunti; Wang, Zhong; Wang, Yongyan



Comparative study of propranolol hydrochloride release from matrix tablets with KollidonSR or hydroxy propyl methyl cellulose.  


The release of propranolol hydrochloride from matrix tablets with hydroxy propyl methyl cellulose (HPMC K15M) or KollidonSR at different concentrations was investigated with a view to developing twice daily sustained release dosage form. A hydrophilic matrix-based tablet using different concentrations of HPMC K15M or KollidonSR was developed using direct compression technique to contain 80 mg of propranolol hydrochloride. The resulting matrix tablets prepared with HPMC K15M or KollidonSR fulfilled all the official requirements of tablet dosage forms. Formulations were evaluated for the release of propranolol hydrochloride over a period of 12 h in pH 6.8 phosphate buffer using USP type II dissolution apparatus. Propranolol hydrochloride and pure KollidonSR or HPMC K15M compatibility interactions was investigated by using Fourier-transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). FTIR spectroscopic and DSC studies revealed that there was no well defined chemical interaction between propranolol hydrochloride with KollidonSR or HPMC K15M. Tablets were exposed to 40 degrees C/75% of RH in open disc for stability. The in vitro drug release study revealed that HPMC K15 at a concentration of 40% of the dosage form weight was able to control the release of propranolol hydrochloride for 12 h, exhibit non-Fickian diffusion with first-order release kinetics where as at 40% KollidonSR same dosage forms show zero-order release kinetics. In conclusion, the in vitro release profile and the mathematical models indicate that release of propranolol hydrochloride can be effectively controlled from a single tablet using HPMC K15M or KollidonSR matrix system. PMID:18459050

Sahoo, J; Murthy, P N; Biswal, S; Sahoo, S K; Mahapatra, A K



Using tablet computers compared to interactive voice response to improve subject recruitment in osteoporosis pragmatic clinical trials: feasibility, satisfaction, and sample size  

PubMed Central

Introduction Pragmatic clinical trials (PCTs) provide large sample sizes and enhanced generalizability to assess therapeutic effectiveness, but efficient patient enrollment procedures are a challenge, especially for community physicians. Advances in technology may improve methods of patient recruitment and screening in PCTs. Our study looked at a tablet computer versus an integrated voice response system (IVRS) for patient recruitment and screening for an osteoporosis PCT in community physician offices. Materials and methods We recruited women ? 65 years of age from community physician offices to answer screening questions for a hypothetical osteoporosis active comparator PCT using a tablet computer or IVRS. We assessed the feasibility of these technologies for patient recruitment as well as for patient, physician, and office staff satisfaction with the process. We also evaluated the implications of these novel recruitment processes in determining the number of primary care practices and screened patients needed to conduct the proposed trial. Results A total of 160 women (80% of those approached) agreed to complete the osteoporosis screening questions in ten family physicians’ offices. Women using the tablet computer were able to complete all screening questions consistently and showed a nonsignificant trend towards greater ease of use and willingness to spend more time in their physician’s office compared to those using IVRS. Using the proportion of women found to be eligible in this study (almost 20%) and other eligibility scenarios, we determined that between 240 and 670 community physician offices would be needed to recruit ample patients for our hypothetical study. Conclusion We found good satisfaction and feasibility with a tablet computer interface for the recruitment and screening of patients for a hypothetical osteoporosis PCT in community office settings. In addition, we used this experience to estimate the number of research sites needed for such a study. PMID:23807841

Mudano, Amy S; Gary, Lisa C; Oliveira, Ana L; Melton, Mary; Wright, Nicole C; Curtis, Jeffrey R; Delzell, Elizabeth; Harrington, T Michael; Kilgore, Meredith L; Lewis, Cora Elizabeth; Singh, Jasvinder A; Warriner, Amy H; Pace, Wilson D; Saag, Kenneth G



Formulation and evaluation of fast dissolving tablet containing domperidone ternary solid dispersion  

PubMed Central

Introduction: Fast dissolving tablet containing domperidone ternary solid dispersion was developed to improve the dissolution of drug and stability of solid dispersion. Materials and Methods: Binary and ternary solid dispersions were prepared by fusion method. They were characterized by solubility study, in vitro dissolution, dissolution efficiency, and stability study. The solid state properties of solid dispersions were characterized by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). Ternary solid dispersion was successfully incorporated into fast dissolving tablet by direct compression method. Tablets were characterized for pre-compression parameters, post-compression parameters, and stability study. Results: Optimized ternary solid dispersion containing ratio 1:2:1.5 of drug: Gelucire 50/13: Poloxamer 188 gave maximum dissolution. The FTIR, DSC, and XRD studies of solid dispersions were confirmed the formation of solid dispersion. Ternary solid dispersion was more stable compared to binary solid dispersion at accelerated environment conditions for one month as confirmed by DSC study. Crospovidone as a superdisintegrant (4%) showed good result with disintegration time of 19 s and dissolution near to 100% in 0.1N HCL at 30 min. Conclusion: The studies indicated that the dissolution of drug and stability of solid dispersion was improved in the presence of ternary agent (surfactant) as compared to binary solid dispersion. It was concluded that fast dissolving tablet containing ternary solid dispersion was stable at accelerated environmental conditions for 1 month.

Patel, Dasharath M.; Patel, Sweeti P.; Patel, Chhagan N.



Formulation and Evaluation of Alstonia boonei Stem Bark Powder Tablets  

PubMed Central

The aim of this work was to formulate Alstonia boonei dried stem bark powder into tablets by wet granulation method using acacia, gelatine and sodium carboxymethyl cellulose as binders at concentrations of 1, 2, 4 and 8% w/w. The phytochemistry of the stem bark of Alstonia boonei was evaluated. The micromeritic properties of the granules prepared were studied. The tablets were evaluated using the necessary official and unofficial tests. The results of the phytochemical analysis showed that alkaloids, tannins, steroids, saponins, glycosides, flavonoids and terpenoids were present while anthroquinones and acidcompounds were absent. Micromeritic studies showed that Alstonia boonei granules had good flowability. The formulated tablets complied with British Pharmacopoeial specification for weight uniformity, hardness (?5 kgf) and tablet friability (<1%). For disintegration test, tablets formulated with gelatine and acacia at concentrations of 1, 2 and 4% w/w complied with Pharmacopoeial specification. However, tablets formulated with SCMC (1-8% w/w) and 8% w/w of acacia and gelatine failed the disintegration tests (Disintegration time more than 15 min). PMID:24019574

Chime, Salome A.; Ugwuoke, E. C.; Onyishi, I. V.; Brown, S. A.; Onunkwo, G. C.



Design and evaluation of fast dissolving tablets containing diclofenac sodium using fenugreek gum as a natural superdisintegrant  

PubMed Central

Objective To formulate diclofenac sodium as fast dissolving tablets (FDTs) using fenugreek gum as a natural superdisintegrant which also possess anti-inflammatory activity. Methods An attempt was made to extract the fenugreek gum and evaluated it for various physicochemical characterizations. The swelling index and viscosity of fenugreek gum was 221% and 293.4 mpa.s respectively. FDTs of diclofenac sodium was formulated by direct compression technique using different concentrations (1%-6%, w/w) of fenugreek gum as a natural superdisintegrant and compared with renowned synthetic superdisintegrants like sodium starch glycolate and croscarmellose sodium. The anti-inflammatory activity of a formulation was evaluated with carrageenan induced experimental rats. Results The formulated tablets were evaluated for various physical tests like weight variation, friability, hardness and results complied with the limits. The drug release from all the formulations ascertained first order kinetics. Among all the formulations F3 containing fenugreek gum with the concentration of 6% produced least disintegrating time 21 seconds resulting in higher drug release rate 93.74% at the end of 25 min. Hence, it was considered as optimized formulation. The present study revealed that the fenugreek gum as a natural superdisintegrant showed better disintegrating property than the most widely used synthetic superdisintegrants like sodium starch glycolate and croscarmellose sodium in the formulations of FDTs. Conclusions The results suggested that the fenugreek gum act as a good super disintegrating agent and it showed promising additive anti-inflammatory activity with diclofenac sodium.

Kumar, M. Uday; Babu, M. Kishore



Effect of different excipients on the physical characteristics of granules and tablets with carbamazepine prepared with polyethylene glycol 6000 by fluidized hot-melt granulation (FHMG).  


The objective of this study was to investigate the properties of granules and tablets with carbamazepine which were prepared employing a fluidized hot-melt granulation (FHMG) technique. The FHMG process was carried out at 65°C. Macrogol 6000 (PEG 6000) was used as a binder at the content 10% (w/w) of the granulated mass. Granules containing up to 70% (w/w) of the drug and 20-90% (w/w) of a filler (lactose, mannitol, calcium hydrogen phosphate (Di-Cafos), pregelatinized starch, and microcrystalline cellulose (MCC)) were produced. When the drug content was 30% (w/w), the yield of the process was satisfying (>95%) and flowability of the granules was better than placebo granules or drug-loaded granules prepared by wet granulation. Type of a filler had strong impact on physical properties of granules, and size distribution of the particles was the most homogenous when lactose or Di-Cafos were used. The FHMG technique enabled preparation of granules with better compressability compared with the wet-granulated product or with non-granulated powders. Tablets with shorter disintegration time than 10 min were obtained with 2.0% crospovidone added as a disintegrant. In comparison to tablets prepared from the wet-granulated mass, employment of the FHMG method resulted in tablets with faster dissolution of carbamazepine (more than 80% of the drug released within 15 min). This was achieved with mannitol or lactose/MCC, as fillers. PMID:21948307

Kraciuk, Rados?aw; Sznitowska, Malgorzata



Relative bioavailability of iron and folic acid from a new powdered supplement compared to a traditional tablet in pregnant women  

PubMed Central

Background Deficiencies of iron and folic acid during pregnancy can lead to adverse outcomes for the fetus, thus supplements are recommended. Adherence to current tablet-based supplements is documented to be poor. Recently a powdered form of micronutrients has been developed which may decrease side-effects and thus improve adherence. However, before testing the efficacy of the supplement as an alternate choice for supplementation during pregnancy, the bioavailability of the iron needs to be determined. Our objective was to measure the relative bioavailability of iron and folic acid from a powdered supplement that can be sprinkled on semi-solid foods or beverages versus a traditional tablet supplement in pregnant women. Methods Eighteen healthy pregnant women (24 – 32 weeks gestation) were randomized to receive the supplements in a crossover design. Following ingestion of each supplement, the changes (over baseline) in serum iron and folate over 8 hours were determined. The powdered supplement contained 30 mg of iron as micronized dispersible ferric pyrophosphate with an emulsifier coating and 600 ?g folic acid; the tablet contained 27 mg iron from ferrous fumarate and 1000 ?g folic acid. Results Overall absorption of iron from the powdered supplement was significantly lower than the tablet (p = 0.003). There was no difference in the overall absorption of folic acid between supplements. Based on the differences in the area under the curve and doses, the relative bioavailability of iron from powdered supplement was lower than from the tablet (0.22). Conclusion The unexpected lower bioavailability of iron from the powdered supplement is contrary to previously published reports. However, since pills and capsules are known to be poorly accepted by some women during pregnancy, it is reasonable to continue to explore alternative micronutrient delivery systems and forms of iron for this purpose. Trial Registration NCT00789490 PMID:19635145

Hartman-Craven, Brenda; Christofides, Anna; O'Connor, Deborah L; Zlotkin, Stanley



Disintegration of porous polyethylene prostheses.  


A Plastipore (porous polyethylene) Total Ossicular Replacement Prosthesis gave an excellent initial hearing result which was maintained for 14 years. Hearing then began to deteriorate and revision surgery showed disintegration of the prosthesis and a defect in the stapes footplate. Histological examination confirmed previous findings in porous polyethylene with multinucleated foreign body giant cells and breakdown of the material. PMID:10384839

Kerr, A G; Riley, D N



The Disintegration of Teacher Preparation  

ERIC Educational Resources Information Center

The disintegration of teacher certification programs in the united States holds an eerie similarity to the recent meltdown of American financial institutions. Similarly, the No Child Left Behind Act of 2001, whose purported purpose was to ensure that all students get highly qualified teachers (HQT), has had an unintentionally devastating effect on…

Baines, Lawrence A.



Taste masked microspheres of ofloxacin: formulation and evaluation of orodispersible tablets.  


Ofloxacin is a synthetic chemotherapeutic antibiotic used for treatment of a variety of bacterial infections, but therapy suffers from low patients' compliance due to its unpleasant taste. This study was aimed to develop taste masked microspheres of ofloxacin using Eudragit and to prepare orodispersible tablets of the formulated microspheres using natural superdisintegrant. Taste masking Eudragit E100 microspheres were prepared by solvent evaporation technique with an entrapment efficiency ranging from 69.54 ± 1.98 to 86.52 ± 2.25%. DSC revealed no interaction between the drug and polymer. Microspheres prepared at a drug/polymer ratio of 1:4 and 1:5 revealed sufficient flow properties and better taste masking as compared to other ratios. Drug loaded microspheres were formulated as orodispersible tablets using locust bean gum as a natural superdisintegrant offering the advatages of biocompatibility and biodegrad-ability. The wetting time, water absorption ratio and in-vitro disintegration time of the tablets were found to range between 19 ± 2 to 10 ± 3 seconds, 59.11 ± 0.65 to 85.76 ± 0.96 and 22 ± 2 to 10 ± 2 seconds, respectively. The in-vitro ofloxacin release was about 97.25% within 2h. The results obtained from the study suggested the use of eudragit polymer for preparing ofloxacin loaded microspheres with an aim to mask the bitter taste of the drug and furthermore orodispersible tablets could be formulated using locust bean gum as a natural superdisintegrant. PMID:21886910

Malik, Karan; Arora, Gurpreet; Singh, Inderbir



Preparation and evaluation of sublingual tablets of zolmitriptan  

PubMed Central

Aim: Zolmitriptan is a 5-HT receptor agonist (1B/1D). It is used in the acute treatment of migraine having low bioavailability about 40% orally due to hepatic first pass metabolism. The purpose of the present research was to formulate fast acting sublingual tablets of zolmitriptan. Materials and Methods: Sublingual tablets were prepared using ispaghula husk powder, gellan gum, sodium alginate as super disintegrating polymers and citric acid, tartaric acid and camphor as permeation enhancers by direct compressible technique and evaluated for weight variation, thickness, friability, content uniformity, hardness, disintegration time, wetting time, in-vitro drug release, in-vitro and ex-vivo permeation study. Stability study of optimized formulation was performed as per ICH (International Conference on Harmonisation) guideline. Results: The in-vitro disintegration time of the optimized formulation (D5) was 9 ± 2 s and all formulations showed 100% of dissolution within 6 ± 2 min. Formulation containing 4% of gellan gum (D5) showed highest disintegration and 2% of citric acid formulation (P3) showed highest permeation 88% within 30 min and ex-vivo permeation was 52% within 30 min. Optimized formulation was stable for 1 month during stability study as per ICH guideline. Conclusion: The sublingual tablet formulation gives better results using natural super disintegrant for fast onset of action. PMID:24678459

Prajapati, Shailesh T; Patel, Manoj V; Patel, Chhaganbhai N



Comparative Bioavailability and Tolerability of Single and Multiple Doses of 2 Diclofenac Sodium Sustained-Release Tablet Formulations in Fasting, Healthy Chinese Male Volunteers?  

PubMed Central

Background Diclofenac is a nonsteroidal anti-inflammatory drug used for the treatment of patients with osteoarthritis. Objectives Our primary objective was to compare bioavailability and tolerability of a generic sustained-release tablet with the established reference sustained-release tablet of diclofenac sodium in a fasting, healthy Chinese male population. Methods A randomized, open-label, single- and multiple-dose study design was used. After the single dose, volunteers received diclofenac sodium sustained-release tablet once daily for 5 days. In the single-dose phase, blood samples were collected from 0 to 36 hours after drug administration. In the multiple-dose phase, samples were obtained before drug administration at 8:00 am on Days 3 and 4 to determine Cmin,ss of diclofenac sodium; on Day 5, samples were collected from 0 to 36 hours. Adverse events were monitored via subject interview, vital signs, and blood sampling. Results Twenty-four Chinese male volunteers were enrolled. The pharmacokinetic parameters (mean [SD]) for diclofenac after single dose of 75 and 100 mg were: Cmax 473.5 [179.5] and 546.6 [154.9] ng/mL; AUC0–? 3841.2 [1402.3], and 5019.1 [2,314.0] ng·h/mL; Tmax 4.9 [2.4], and 4.3 [2.2] hours; t1/2 5.9 [2.5], and 6.0 [2.2] hours. Mean [SD] values after multiple doses of 75 and 100 mg were: Cmax,ss 525.6 [127.4] and 650.5 [167.0] ng/mL, Cmin,ss 33.9 [20.9] and 62.9 [34.9] ng/mL, AUCss 4316.3 [633.0] and 5335.1 [1291.9] ng·h/mL, Cav,ss 179.8 [26.4] and 222.3 [53.8] ng/mL, Tmax 5.1 [1.8] and 4.5 [0.9] hours and t1/2 5.2 [2.9] and 5.5 [2.8] hours, respectively. Conclusions This diclofenac sodium 75 mg tablet has features compatible with the 100 mg sustained-release tablet and appeared to be well tolerated. identifier: 2010L01969 PMID:24465044

Zhai, Xue-Jia; Yu, Ye; Chen, Fen; Lu, Yong-Ning



PA02.04. A comparative study of loha rasayana prepared by ayaskriti and modified method w.s.r. disintegration of Iron.  

PubMed Central

Purpose: Loha Rasayana one of the important Rasayana referred in Charaka Samhita is known for its Rasayana effect. This approach to the formulations was so rational and perfect that it fulfils the expectation of the scientific masses even also in terms of today's Nanoparticle theory. This technique got improvised with time and experience and is now used to make the Bhasmas. Purpose of present study was to scrutinize the validation of the process referred in Charaka Samhita to render the metal therapeutically suitable to the body and procedure by which the Bhasmas are prepared and to analyse them on ancient and modern parameters. Method: •Loha Rasayana was prepared as per Cha.Chi. 13/1523 by using Ayaskriti. •Samples were collected and subjected to analysis at different interval of time to trace the ongoing changes in the medicine. •Loha Rasayana was analytically compared with the Bhasma and also with a sample of Loha Rasayana prepared by using Bhasma on ancient and modern parameters. •The samples were subjected to XRD, ICPAES, SEM, Organoleptic tests, Physico chemical, Assay of Iron Content, Particle size, TLC and Alcohol Content. Result: Analytical Tests: LRA LRB Particle Size(200) 68.0% 88%, Particle Size (325) 4% 7%, TLC (Rf) 0.25 0.024, Alcohol content %2.12% 4.28%, ICP AES (Fe) % 66.45% 51.32%, Total Iron Content %36.40 43.50, Ferrous Content %7.23 7.09, Ferric Content % 29.49 37.91, XRD Hematite & Magnetite Hematite Conclusion: Submersion of Iron in Acidic media for 12 months reduced Iron to 68% and 88% of the Ayaskriti and Bhasma to pass through 200 mess size. Alcohol content of the samples was well within the limit (2.12% and 4.28) and Ferrous content were found to increase in both samples to 7.23% & 7.09%.

Baijnath, P Anjali; Meena, Moharpal



Preliminary evaluation of dika fat, a new tablet lubricant.  


Dika fat, a solid vegetable oil extracted from the kernels of Irvingia gabonensis var excelsia has been evaluated as a lubricant on the basis of its effect on the flow rate of granules, disintegration time and dissolution rate of tablets. The fat shows a maximal effect on flow at a concentration of 2.5% w/w. It produces better disintegration and dissolution profiles than magnesium stearte at all concentrations tested. The indication is that there is less degradation of aspirin in tablets containing this oil than there is in tablets containing magnesium stearate. The use of Dika fat (m.p. 39--40 degrees C) eliminates the hydrogenation step often necessary for vegetable oils. PMID:6102130

Udeala, O K; Onyechi, J O; Agu, S I



Cost-effectiveness of the once-daily efavirenz/emtricitabine/tenofovir tablet compared with the once-daily elvitegravir/cobicistat/emtricitabine/tenofovir tablet as first-line antiretroviral therapy in HIV-infected adults in the US  

PubMed Central

Background February 2013 US treatment guidelines recommend the once-daily tablet of efavirenz/emtricitabine/tenofovir (Atripla®) as a preferred regimen and the once-daily tablet of elvitegravir/cobicistat/emtricitabine/tenofovir (Stribild™) as an alternative regimen for first-line treatment of human immunodeficiency virus (HIV). This study assessed the clinical and economic trade-offs involved in using Atripla compared with Stribild as first-line antiretroviral therapy in HIV-infected US adults. Methods A Markov cohort model was developed to project lifetime health-related outcomes, costs, quality-adjusted life years (QALYs), and cost-effectiveness of Stribild compared with Atripla as first-line antiretroviral therapy in HIV-1-infected US patients. Patients progressed in 12-week cycles through second-line, third-line, and nonsuppressive therapies, acquired immune deficiency syndrome, and death. Baseline characteristics and first-line virologic suppression, change in CD4 count, and adverse effects (lipid, central nervous system, rash, renal) were based on 48-week clinical trial results. These results demonstrated equivalent virologic suppression between the two regimens. Point estimates for virologic suppression (favoring Stribild) were used in the base case, and equivalency was used in the scenario analysis. Published sources and expert opinion were used to estimate costs, utilities, risk of acquired immune deficiency syndrome, mortality, subsequent-line CD4 count, clinical efficacy, and adverse events. Costs were reported in 2012 US dollars. Sensitivity analyses were conducted to assess robustness of results. Results Compared with patients initiating Atripla, patients initiating Stribild were estimated to have higher lifetime costs. Stribild added 0.041 QALYs over a lifetime at an additional cost of $6,886, producing an incremental cost-effectiveness ratio of $166,287/QALY gained. Results were most sensitive to first-line response rates, product costs, and likelihood of renal adverse events. When equivalent efficacy was assumed, Atripla dominated Stribild with lower costs and greater QALYs. Conclusion At a societal willingness to pay of $100,000/QALY, Stribild was not cost-effective in the base case compared with Atripla for first-line HIV treatment. PMID:24039438

Juday, Timothy; Correll, Todd; Anene, Ayanna; Broder, Michael S; Ortendahl, Jesse; Bentley, Tanya



Numerical simulation on zonal disintegration in deep surrounding rock mass.  


Zonal disintegration have been discovered in many underground tunnels with the increasing of embedded depth. The formation mechanism of such phenomenon is difficult to explain under the framework of traditional rock mechanics, and the fractured shape and forming conditions are unclear. The numerical simulation was carried out to research the generating condition and forming process of zonal disintegration. Via comparing the results with the geomechanical model test, the zonal disintegration phenomenon was confirmed and its mechanism is revealed. It is found to be the result of circular fracture which develops within surrounding rock mass under the high geostress. The fractured shape of zonal disintegration was determined, and the radii of the fractured zones were found to fulfill the relationship of geometric progression. The numerical results were in accordance with the model test findings. The mechanism of the zonal disintegration was revealed by theoretical analysis based on fracture mechanics. The fractured zones are reportedly circular and concentric to the cavern. Each fracture zone ruptured at the elastic-plastic boundary of the surrounding rocks and then coalesced into the circular form. The geometric progression ratio was found to be related to the mechanical parameters and the ground stress of the surrounding rocks. PMID:24592166

Chen, Xuguang; Wang, Yuan; Mei, Yu; Zhang, Xin



A randomized, open-label, comparative efficacy trial of artemether-lumefantrine suspension versus artemether-lumefantrine tablets for treatment of uncomplicated Plasmodium falciparum malaria in children in western Kenya  

PubMed Central

Background Artemether/lumefantrine (AL) has been adopted as the treatment of choice for uncomplicated malaria in Kenya and other countries in the region. Six-dose artemether/lumefantrine tablets are highly effective and safe for the treatment of infants and children weighing between five and 25 kg with uncomplicated Plasmodium falciparum malaria. However, oral paediatric formulations are urgently needed, as the tablets are difficult to administer to young children, who cannot swallow whole tablets or tolerate the bitter taste of the crushed tablets. Methods A randomized, controlled, open-label trial was conducted comparing day 28 PCR corrected cure-rates in 245 children aged 6–59 months, treated over three days with either six-dose of artemether/lumefantrine tablets (Coartem®) or three-dose of artemether/lumefantrine suspension (Co-artesiane®) for uncomplicated falciparum malaria in western Kenya. The children were followed-up with clinical, parasitological and haematological evaluations over 28 days. Results Ninety three percent (124/133) and 90% (121/134) children in the AL tablets and AL suspension arms respectively completed followed up. A per protocol analysis revealed a PCR-corrected parasitological cure rate of 96.0% at Day 28 in the AL tablets group and 93.4% in the AL suspension group, p = 0.40. Both drugs effectively cleared gametocytes and were well tolerated, with no difference in the overall incidence of adverse events. Conclusion The once daily three-dose of artemether-lumefantrine suspension (Co-artesiane®) was not superior to six-dose artemether-lumefantrine tablets (Coartem®) for the treatment of uncomplicated malaria in children below five years of age in western Kenya. Trial registration NCT00529867 PMID:19102746

Juma, Elizabeth A; Obonyo, Charles O; Akhwale, Willis S; Ogutu, Bernhards R



Drawbacks of Surfactant Presence on the Dissolution and Mechanical Properties of Detergent Tablets: How to Control Interfaces by Surfactant Localization  

Microsoft Academic Search

The aim of this study is to limit the hurdles generated by the presence of a surfactant, i.e., sodium dodecyl sulfate (SDS),\\u000a in effervescent detergent tablets containing a chlorine provider. The results are highlighted by investigating the tablet’s\\u000a functional characteristics (mechanical strength, disintegration time). A second objective is to increase the surfactant content\\u000a of the tablet in order to improve

Florence Chantraine; Marylène Viana; Christelle Pouget; Nelly Brielles; Olivier Mondain-Monval; Paul Branlard; Gilles Rubinstenn; Dominique Chulia



Evaluation of citrus fibers as a tablet excipient.  


The consumption of fibers is associated with many health benefits, such as a reduction of cardiovascular and gastrointestinal diseases, control of body weight, and prevention of diabetes. Despite the widespread use of fiber supplements such as capsules or tablets, there is an almost complete lack of information concerning the technological properties of functional fibers used in nutraceutical formulations. The aim of this work was to characterize the technological properties of citrus fibers necessary for their use as a processing aid in tableting. The results obtained showed that citrus fibers share many properties of other polysaccharides used as tableting excipients, such as thermal behavior and compaction mechanism, together with an appreciable tabletability. However, the most interesting properties resulted from their disintegration power. Citrus fibers behaved in a similar manner to the well-known super disintegrant croscarmellose sodium and resulted to be little susceptible to their concentration, to lubricant type, and lubricant concentration. Thus, this work supports the idea of a potential use of citrus fibers as "active" substances and processing aid in the tableting of nutraceutical products and also as functional excipient in pharmaceutical tablets formulation. PMID:24306677

Cespi, Marco; Bonacucina, Giulia; Roberts, Matthew; Hanson, Samuel; Jones, Stephen; Makevica, Elina; Casettari, Luca; Palmieri, Giovanni Filippo



Formulation and optimization of orodispersible tablets of flutamide  

PubMed Central

The present study aimed to formulate orodispersible tablets of flutamide (FTM) to increase its bioavailability. Orodispersible tablets were prepared by direct compression technique using three different approaches namely; super-disintegration, effervescence and sublimation. Different combined approaches were proposed and evaluated to optimize tablet characteristics. Sodium starch glycolate (SSG) was used as the superdisintegrant. The prepared powder mixtures were subjected to both pre and post compression evaluation parameters including; IR spectroscopy, micromeritics properties, tablet hardness, friability, wetting time, disintegration time and in-vitro drug release. IR studies indicated that there was no interaction between the drug and the excipients used except Ludipress. The results of micromeritics studies revealed that all formulations were of acceptable to good flowability. Tablet hardness and friability indicated good mechanical strength. Wetting and dispersion times decreased from 46 to 38 s by increasing the SSG concentration from 3.33 to 6.66% w/w in tablets prepared by superdisintegration method. The F8 formulation which was prepared by combined approaches of effervescence and superdisintegrant addition gave promising results for tablet disintegration and wetting times but failed to give faster dissolution rate. The incorporation of 1:5 solid dispersion of FTM: PEG 6000 instead of the pure drug in the same formulation increased the drug release rate from 73.12 to 96.99% after 15 min. This increase in the dissolution rate may be due to the amorphization of the drug during the solid dispersion preparation. The presence of the amorphous form of the drug was shown in the IR spectra. PMID:24493974

Elkhodairy, Kadria A.; Hassan, Maha A.; Afifi, Samar A.



Bimodal drug release achieved with multi-layer matrix tablets: transport mechanisms and device design.  


The aim of this study was to develop new multi-layer matrix tablets to achieve bimodal drug release profiles (fast release/slow release/fast release). Hydroxypropyl methylcellulose acetate succinate (HPMCAS, type MF) was chosen as a matrix former, because it is water-insoluble at low, and water-soluble at high pH values. Studies focused on the elucidation of the drug release mechanisms from HPMCAS-MF:drug tablets. In 0.1 N HCl the resulting release kinetics can be described using Fick's second law of diffusion, taking into account axial and radial mass transfer in cylindrical geometry. As the diffusion coefficients are found to be constant and the boundary conditions to be stationary, these systems are purely drug diffusion-controlled. In contrast, the dominating mass transport phenomena in phosphate buffer pH 7.4 are more complex. Due to polymer dissolution the resulting matrix structure is time-variant, leading to increasing drug diffusion coefficients and decreasing tablet dimensions, and thus moving boundary conditions. Drug release is affected by water imbibition, drug diffusion and polymer dissolution and is faster compared to 0.1 N HCl. With knowledge of these underlying release mechanisms, multi-layer matrix tablets were developed to achieve bimodal drug release. HPMCAS-MF:drug mixtures were used as tablet cores. As expected, changing the release medium from 0.1 N HCl to phosphate buffer pH 7. 4 after 2 h, lead to a significant increase in drug release. The abruptness of this rate change could be enhanced by adding two drug-free HPMCAS-MF barrier layers (one on each side) to the system. The addition of a fourth, drug-containing and fast disintegrating initial dose layer yielded the desired bimodal drug release patterns. The process and formulation parameters affecting the resulting release rates were investigated using theophylline and acetaminophen as model drugs. PMID:11102685

Streubel, A; Siepmann, J; Peppas, N A; Bodmeier, R



Preparation of multiparticulate vaginal tablet using glyceryl monooleate for sustained progesterone delivery.  


Most of the sustained release vaginal formulations are in the form of bioadhesive gels and tablets. Though proved efficient, their presence in the vagina for a longer time as a bulk produces discomfort and interference with body functioning including sexual activities. Hence, they lack complete patient compliance. In this study, multiparticulate vaginal tablets were prepared by utilizing progesterone (PRO) loaded dry powder precursor of cubic phase (DPPCP) of glyceryl monooleate (GMO). DPPCP were obtained by spray drying GMO with magnesium trisilicate (MTS) and have presented PRO sustained release in simulated vaginal fluid (SVF) for 14 hours. The effect of hydrophilic and hydrophobic tableting excipients on compression, phase, bioadhesion and drug release properties of prepared tablets was evaluated. The effervescent hydrophilic tablet (EHT) prepared with hydrophilic excipients showed rapid disintegration but, diminished sustaining ability owing to transformation into lamellar phase whereas the multiparticulate hydrophobic tablet (MHT) obtained from hydrophobic excipients presented both rapid disintegration and sustained release in SVF by virtue of cubic phase retention. During bioadhesivity testing, fast disintegration of MHT with formation of uniform and viscous bioadhesive layer on cow mucosa was observed even with a small volume of SVF. As MHT may not produce discomfort and interference, it will be preferred over bioadhesive gel or tablet. PMID:18802845

Biradar, Shailesh V; Dhumal, Ravindra S; Shah, Manish H; Paradkar, Anant R; Yamamura, Shigeo



Properties of gastroretentive sustained release tablets prepared by combination of melt/sublimation actions of L-menthol and penetration of molten polymers into tablets.  


A novel floating sustained release tablet having a cavity in the center was developed by utilizing the physicochemical properties of L-menthol and the penetration of molten hydrophobic polymer into tablets. A dry-coated tablet containing famotidine as a model drug in outer layer was prepared with a L-menthol core by direct compression. The tablet was placed in an oven at 80°C to remove the L-menthol core from tablet. The resulting tablet was then immersed in the molten hydrophobic polymers at 90°C. The buoyancy and drug release properties of tablets were investigated using United States Pharmacopeia (USP) 32 Apparatus 2 (paddle 100 rpm) and 900 ml of 0.01 N HCl. The L-menthol core in tablets disappeared completely through pathways in the outer layer with no drug outflows when placed in an oven for 90 min, resulting in a formation of a hollow tablet. The hollow tablets floated on the dissolution media for a short time and the drug release was rapid due to the disintegration of tablet. When the hollow tablets were immersed in molten hydrophobic polymers for 1 min, the rapid drug release was drastically retarded due to a formation of wax matrices within the shell of tablets and the tablets floated on the media for at least 6 h. When Lubri wax® was used as a polymer, the tablets showed the slowest sustained release. On the other hand, faster sustained release properties were obtained by using glyceryl monostearate (GMS) due to its low hydrophobic nature. The results obtained in this study suggested that the drug release rate from floating tablets could be controlled by both the choice of hydrophobic polymer and the combined use of hydrophobic polymers. PMID:21963630

Fukuda, Mamoru; Goto, Akinori



Evaluation of dika nut mucilage (Irvingia gabonensis) as binding agent in metronidazole tablet formulations.  


Dika nut mucilage obtained from the nuts of Irvingia gabonensis (O'Rorke) Bail (family Irvingiaceae) has been evaluated as a binding agent in metronidazole tablet formulations in comparison with gelatin BP. The compressional properties of metronidazole formulations were analyzed using density measurements and the Heckel equations as assessment parameters, whereas the mechanical properties of the tablets were assessed using the tensile strength (T), brittle fracture index (BFI), and the friability of the tablets. The drug release properties of the tablets were assessed using disintegration and dissolution times of the tablets. The results obtained indicate that formulations containing dika nut mucilage as binding agent show faster onset of plastic deformation under compression pressure than those containing gelatin. The tensile strength of the tablets increased with increase in concentration of the binding agents, whereas the BFI and friability values decreased. Furthermore, tablets containing dika nut mucilage generally showed lower tensile strength but higher brittleness and friability than those containing gelatin. The results also showed that tablets containing dika nut mucilage generally showed higher disintegration and dissolution times than those containing gelatin BP. The results suggest that dika nut mucilage could be useful in achieving various tablet strength and drug release properties. PMID:16176024

Odeku, Oluwatoyin A; Patani, Bernard O



156 Economic Evaluation of Grass Tablets for Immunotherapy (oralair) Compared to Placebo in Adults and Children in Italy  

PubMed Central

Background Specific immunotherapy is based on the regular administration over time of a maintenance dose of allergen extracts to allergic patients in order to modify the immune response, thus achieving a decrease in symptoms/drug intake and an improvement in quality of life, possibly on the long-term. Grass pollen tablet, Oralair (Stallergenes, Antony Cedex, France), were developed and registered for rhinoconjunctivitis allergy induced by grass pollen. There is sufficient evidence for the clinical efficacy of the product, but pharmaco-economy data are lacking. Methods An economic analysis, using a rescue medication adjusted score (AASS) was performed, based on the available registration trials—to assess the magnitude of Oralair effect if patients had not taken any rescue medication. In the present study the results of an adult and a pediatric study are pooled together with economic data in order to perform a cost–effectiveness analysis from the third party payer perspective. Medical visits, diagnostic exams, skin prick test, and drugs were valorized in euros according to the National tariffs and the standard drug prices in the Italian setting. The estimated ROC also enabled us to quantify the effectiveness in terms of Quality Adjusted Life Years (QALY). A decision tree was structured in order to model the possible outcomes and costs, according to a low, moderate and high AASS in adults and pediatric patients. A probabilistic sensitivity analysis was finally conducted to test the robustness of the results as well as the consistency with an assumed cost effectiveness threshold of euros 30.000/QALY. Results The results showed a relative difference of 1.84 in favor of the active treatment versus placebo in absolute value in adult study and of 1.64 in pediatric study. The results also show how the Oralair administration costs 1024 euro/QALY with high and moderate AASS. Including also the loss of productivity the incremental cost-effectiveness ratio (ICER) in adults is 700 euro/QALY. The 95% of the simulation performed by sensitivity analysis shows an ICER below the threshold of 30.000 euro/QALY. Conclusions In conclusion our results show that Oralair grass tablet is a cost effective strategy in adults and pediatric patients with moderate and severe AASS.

Cicchetti, Amerigo; Ruggeri, Matteo; Fiocchi, Alessandro; Bonini, Sergio; Puccinelli, Paola; Passalacqua, Giovanni; Frati, Franco



Colonic release and reduced intestinal tissue damage of coated tablets containing naproxen inclusion complex.  


A colonic-release delivery system containing naproxen inclusion complex with 2-hydroxypropyl-beta-cyclodextrin (2-HPbetaCD) was originally proposed. The core tablets consisting of the naproxen inclusion complex and disintegrants (Ac-Di-Sol), Primojel), Avicel) or Polyplasdone) were formed by direct compression, and then coated with the polymers, either pH-dependent Eudragit S100 and/or pH-independent Eudragit RS100 with plasticizers like dibutyl sebacate (DBS) and aluminum tristearate (AT). The in vitro release characteristics were evaluated in simulated gastric fluid for 2h and then subsequently in simulated intestinal fluid for 12h. The potential histological changes were also evaluated after direct dosing of suspensions of naproxen alone and powdered mixtures of inclusion complex-loaded tablet into rat intestinal segments. No distinct colonic release was observed when disintegrants were excluded in the single-layered coated tablets regardless of coated structures, giving a zero-order fashion over 12h. The coated tablet with double-layered structures of Eudragit S100 and Eudragit RS100 was not also applicable. In contrast, colonic release was achieved when the core tablet containing inclusion complex and disintegrant was coated with only Eudragit S100 in a single-layered structure. The colonic-release tablet was resistant in gastric fluid for 2h and for 2-4h in intestinal fluid, followed by rapid release of the drug after a total of 4-6h of lag time depending on the type of disintegrants. The lag time was advanced in case of DBS while delayed in case of AT. On histological examination, the inclusion complex-loaded suspension caused less intestinal tissue damage than naproxen alone. Based on these findings, the colonic-release tablet with enteric coatings which contains inclusion complex and disintegrants could be useful to deliver drugs like naproxen to the lower small intestine and upper colon with increased dissolution and reduced intestinal tissue damage. PMID:17928177

Piao, Zong-Zhu; Lee, Mi-Kyung; Lee, Beom-Jin



Apparatus for disintegrating kidney stones  

NASA Technical Reports Server (NTRS)

The useful life of the wire probe in an ultrasonic kidney stone disintegration instrument is enhanced and prolonged by attaching the wire of the wire probe to the tip of an ultrasonic transducer by means of a clamping arrangement. Additionally, damping material is applied to the wire probe in the form of a damper tube through which the wire probe passes in the region adjacent the transducer tip. The damper tube extends outwardly from the transducer tip a predetermined distance, terminating in a resilient soft rubber joint. Also, the damper tube is supported intermediate its length by a support member. The damper system thus acts to inhibit lateral vibrations of the wire in the region of the transducer tip while providing little or no damping to the linear vibrations imparted to the wire by the transducer.

Angulo, E. D. (inventor)



Effect of diluents on tablet integrity and controlled drug release.  


The objective of this study was to evaluate the effect of diluents and wax level on tablet integrity during heat treatment and dissolution for sustained-release formulations and the resultant effect on drug release. Dibasic calcium phosphate dihydrate (DCPD), microcrystalline cellulose (MCC), and lactose were evaluated for their effect on tablet integrity during drug dissolution and heat treatment in wax matrix formulations. A newly developed direct compression diluent, dibasic calcium phosphate anhydrous (DCPA), was also evaluated. Compritol 888 ATO was used as the wax matrix material, with phenylpropanolamine hydrochloride (PPA) as a model drug. Tablets were made by direct compression and then subjected to heat treatment at 80 degrees C for 30 min. The results showed that MCC, lactose, and DCPA could maintain tablets intact during heat treatment above the melting point of wax (70 degrees C-75 degrees C). However, DCPD tablets showed wax egress during the treatment. MCC tablets swelled and cracked during drug dissolution and resulted in quick release. DCPD and lactose tablets remained intact during dissolution and gave slower release than MCC tablets. DCPA tablets without heat treatment disintegrated very quickly and showed immediate release. In contrast, heat-treated DCPA tablets remained intact through the 24-hr dissolution test and only released about 80% PPA at 6 hr. In the investigation of wax level, DCPD was used as the diluent. The drug release rate decreased as the wax content increased from 15% to 81.25%. The dissolution data were best described by the Higuchi square-root-of-time model. Diluents showed various effects during heat treatment and drug dissolution. The integrity of the tablets was related to the drug release rate. Heat treatment retarded drug release if there was no wax egress. PMID:10872095

Zhang, Y E; Schwartz, J B



Bioequivalence of Clozapine Tablets  

Microsoft Academic Search

Objective To perform a bioequivalence study of clozapine tablets between Clozaril ? tablet (Novartis), the innovator product, and Clopaze ? tablet (Pharminar, Thailand). Method The study was performed in 12 healthy male volunteers for a single 100 mg dose of clozapine tablet. Randomized cross over design was used. Blood samples were collected before and after drug administration for 24 hours

Wandee Taesotikul; Sayam Kaewvichit; Chokchai Wongsinsup; Kittipong Sanichwankul; Wanida Pumpaisalchai



The influence of formulation on the dissolution profile of diclofenac sodium tablets.  


In attempts to design delayed-release tablets of diclofenac sodium, seven experimental batches were produced. The influence of super-disintegrant croscarmellose sodium (CCS), the granulation process, and the thickness of Eudragit L 100 coating film were evaluated. The values of dissolution efficiency and the similarity factor were used to compare the dissolution profiles of each experimental batch and the reference Voltaren. Both methods appear to be applicable and useful in comparing dissolution profiles. Based on such values four batches were considered similar when contrasted with the reference. The results suggest an optimal relationship between the amount of CCS and the thickness of the coating film, which provides appropriate dissolution rate of diclofenac sodium from the dosage forms. PMID:17012123

De Castro, W V; Pires, M A S; Oliveira, M A; Vianna-Soares, C D; Nunan, E A; Pianetti, G A; Moreira-Campos, L M; De Castro, W V; Mertens-Talcott, S U; Derendorf, H



Quality-by-design case study: investigation of the role of poloxamer in immediate-release tablets by experimental design and multivariate data analysis.  


The role of poloxamer 188, water and binder addition rate, on retarding dissolution in immediate-release tablets of a model drug from BCS class II was investigated by means of multivariate data analysis (MVDA) combined with design of experiments (DOE). While the DOE analysis yielded important clues into the cause-and-effect relationship between the responses and design factors, multivariate data analysis of the 40+ variables provided additional information on slowdown in tablet dissolution. A steep dependence of both tablet dissolution and disintegration on the poloxamer and less so on other design variables was observed. Poloxamer was found to increase dissolution rates in granules as expected of surfactants in general but retard dissolution in tablets. The unexpected effect of poloxamer in tablets was accompanied by an increase in tablet-disintegration-time-mediated slowdown of tablet dissolution and by a surrogate binding effect of poloxamer at higher concentrations. It was additionally realized through MVDA that poloxamer in tablets either acts as a binder by itself or promotes binder action of the binder povidone resulting in increased intragranular cohesion. Additionally, poloxamer was found to mediate tablet dissolution on stability as well. In contrast to tablet dissolution at release (time zero), poloxamer appeared to increase tablet dissolution in a concentration-dependent manner on accelerated open-dish stability. Substituting polysorbate 80 as an alternate surfactant in place of poloxamer in the formulation was found to stabilize tablet dissolution. PMID:21861241

Kaul, Goldi; Huang, Jun; Chatlapalli, Ramarao; Ghosh, Krishnendu; Nagi, Arwinder




PubMed Central

The present study was an attempt to formulate and evaluate enteric coated tablets for esomeprazole magnesium trihydrate. Different core tablets were prepared and formulation (F-1) was selected for further enteric coating, based on the disintegration time. Seal coating was applied to achieve 3% weight gain using opadry®. Enteric coating was carried out using different polymers like Eudragit L-30 D-55, hydroxy propyl methylcellulose phthalate, cellulose acetate phthalate and Acryl-EZE® to achieve 5% weight gain. Disintegration studies showed that the formulations failed in 0.1 N HCl media. Hence the quantity of enteric coating was increased to 8% w/w. In vitro analysis of the developed tablets was carried out. Results from disintegration time and dissolution rate studies indicate that all the esomeprazole enteric tablets prepared possess good integrity, desirable for enteric coated tablets. Among the polymers studied, the methacrylic polymers exhibited better dissolution rate than the cellulose polymers. Stability studies indicate that the prepared formulations were stable for a period of three months. This study concluded that enteric coated tablets of esomeprazole can be prepared using any of the enteric coating polymer studied using a minimal weight gain of 8%. PMID:24825991

Nair, Anroop B; Gupta, Rachna; Kumria, Rachna; Jacob, Shery; Attimarad, Mahesh



Evaluation of starches obtained from four Dioscorea species as binding agent in chloroquine phosphate tablet formulations  

PubMed Central

Starches obtained from four Dioscorea species namely Dioscorea dumetorum (Bitter), Dioscorea oppositifolia (Chinese), Dioscorea alata (Water), and Dioscorea rotundata (White) have been evaluated as binding agents in chloroquine phosphate tablet formulations in comparison with official corn starch. The compressional properties of the formulations were analyzed using density measurements and the Heckel and Kawakita equations. The mechanical properties of the tablets were assessed using tensile strength, brittle fracture index (BFI), and friability tests while the drug release properties of the tablets were assessed using disintegration and dissolution times. The results indicate that the four starches vary considerably in their physicochemical properties. The ranking for the tensile strength and the disintegration and dissolution times for the formulations was Chinese > Bitter > Corn > White > Water while the ranking was reversed for BFI and friability. The results suggest that Water, White, and Corn could be useful when faster disintegration time of tablets is desired while Chinese and Bitter could be more useful when bond strength is of concern and in minimizing the problems of lamination and capping in tablet formulation. PMID:23960747

Okunlola, Adenike; Odeku, Oluwatoyin A.



A single-dose, three-period, six-sequence crossover study comparing the bioavailability of solution, suspension, and enteric-coated tablets of magnesium valproate in healthy Mexican volunteers under fasting conditions  

Microsoft Academic Search

Background: Valproic acid has been associated with a highly variable intersubject absorptive phase; therefore, magnesium salt (magnesium valproate [MgV]) was developed to diminish variation during enteric absorption.Objectives: The aims of this study were to assess the pharmacokinetics of single oral doses of MgV 500-mg solution, suspension, and enteric-coated tablets in a healthy Mexican population, and to compare formulation-related differences.Methods: This

Gabriel Marcelín-Jiménez; Alionka P. Angeles-Moreno; Leticia Contreras-Zavala; Miriam Morales-Martínez; Liliana Rivera-Espinosa



Influence of process variables on release properties of paracetamol tablets.  


A 2(3) factorial experimental design has been used to quantitatively study individual and interaction effects of the nature of binder (N), binder concentration (c) and relative density of tablet (d) on the disintegration time (DT) and dissolution times, t1, t50 and t90, of paracetamol tablet formulations. The factorial design was also used to study the quantitative effects of pregelatinization of starch binders on these parameters, i.e., N, c and d. In general, the most common ranking of the individual effects on DT, t1, t50 and t90 for native/native, pregelatinized/pregelatinized and native/pregelatinized starch binder formulations was c > d > N. For interaction effects, the most common ranking was N-c > c-d > N-d for all formulations. The results generally showed that c can considerably affect DT, t1, t50 and t90 of the tablets. PMID:19839408

Alebiowu, Gbenga; Itiola, Oludele Adelanwa



Preparation and biological efficacy of haddock bone calcium tablets  

NASA Astrophysics Data System (ADS)

To investigate the possible use of waste products obtained after processing haddock, the present study prepared haddock bone calcium powder by NaOH and ethanol soaking (alkalinealcohol method) and prepared haddock bone calcium tablets using the powder in combination with appropriate excipients. The biological efficacy of the haddock bone calcium tablets was investigated using Wistar rats as an experiment model. Results show that the optimal parameters for the alkalinealcohol method are: NaOH concentration 1 mol/L, immersion time 30 h; ethanol concentration 60%, immersion time 15 h. A mixture of 2% polyvinylpyrrolidone in ethanol was used as an excipient at a ratio of 1:2 to full-cream milk powder, without the use of a disintegrating agent. This process provided satisfactory tablets in terms of rigidity and taste. Animal studies showed that the haddock bone calcium tablets at a dose of 2 g·kg-1·d-1 or 5g·kg-1·d-1 significantly increased blood calcium and phosphorus levels and bone calcium content in rats. Therefore, these tablets could be used for calcium supplementation and prevent osteoporosis. Although the reasons of high absorption in the rats fed with haddock bone calcium tablets are unclear, it is suggested that there are some factors, such as treatment with method of alkaline-alcohol or the added milk, may play positive roles in increasing absorption ratio.

Huo, Jiancong; Deng, Shanggui; Xie, Chao; Tong, Guozhong



Model test of anchoring effect on zonal disintegration in deep surrounding rock masses.  


The deep rock masses show a different mechanical behavior compared with the shallow rock masses. They are classified into alternating fractured and intact zones during the excavation, which is known as zonal disintegration. Such phenomenon is a great disaster and will induce the different excavation and anchoring methodology. In this study, a 3D geomechanics model test was conducted to research the anchoring effect of zonal disintegration. The model was constructed with anchoring in a half and nonanchoring in the other half, to compare with each other. The optical extensometer and optical sensor were adopted to measure the displacement and strain changing law in the model test. The displacement laws of the deep surrounding rocks were obtained and found to be nonmonotonic versus the distance to the periphery. Zonal disintegration occurs in the area without anchoring and did not occur in the model under anchoring condition. By contrasting the phenomenon, the anchor effect of restraining zonal disintegration was revealed. And the formation condition of zonal disintegration was decided. In the procedure of tunnel excavation, the anchor strain was found to be alternation in tension and compression. It indicates that anchor will show the nonmonotonic law during suppressing the zonal disintegration. PMID:23997683

Chen, Xu-Guang; Zhang, Qiang-Yong; Wang, Yuan; Liu, De-Jun; Zhang, Ning



Formulation and evaluation of sublingual tablets containing Sumatriptan succinate  

PubMed Central

Objective: Sumatriptan succinate is a selective 5-hydroxytryptamine-1 receptor agonist effective in the acute treatment of migraine headaches, having low bioavailability of about 15% orally due to first-pass metabolism. The purpose of this research was to mask the intensely bitter taste of Sumatriptan succinate and to formulate fast-acting, taste-masked sublingual tablet formulation. Materials and Methods: Taste masking was performed by solid dispersion method with mannitol and ion exchange with Kyron T 114 because it releases the drug in salivary pH. The resultant batches were evaluated for in-vivo taste masking as well compatability study (Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC)). For a better feel in the mouth, menthol and sweetener Na saccharine were added to the tablet formulation. The tablets were prepared by direct compression and evaluated for weight variation, thickness, friability, drug content, hardness, disintegration time, wetting time, in vitro drug release, and in vitro permeation study. Results and Discussion: Optimized batches disintegrated in vitro within 28-34 s. Maximum drug release could be achieved with in 10 min for the solid dispersion batches and 14-15 min for the ion-exchange batches with Kyron T 114. The optimized tablet formulation showed better taste and the formulated sublingual tablets may act as a potential alternate for the Sumatriptan succinate oral tablet. Conclusion: Sumatriptan succinate can be successfully taste-masked by both the solid dispersion method using mannitol by the melting method and Ion exchange resin with Kyron T114. It was also concluded that prepared formulation improve bioavailability by prevention of first pass metabolism. PMID:23373008

Prajapati, Shailesh T; Patel, Parth B; Patel, Chhagan N



Randomized Clinical Trial Comparing the Pharmacokinetics of Standard- and Increased-Dosage Lopinavir-Ritonavir Coformulation Tablets in HIV-Positive Pregnant Women  

PubMed Central

A lopinavir-ritonavir (LPV/r)-based regimen is recommended during pregnancy to reduce the risk of HIV mother-to-child transmission, but the appropriate dose is controversial. We compared the pharmacokinetics of standard and increased LPV/r doses during pregnancy. This randomized, open-label prospective study enrolled 60 pregnant women between gestational weeks 14 and 30. The participants received either the standard dose (400/100 mg twice a day [BID]) or increased dose (600/150 mg BID) of LPV/r tablets during pregnancy and the standard dose for 6 weeks after childbirth. Pharmacokinetics analysis was performed using a high-performance liquid chromatography-tandem mass spectrometry method. Adherent participants who received the standard dose presented minimum LPV concentrations of 4.4, 4.3, and 6.1 ?g/ml in the second and third trimesters and postpartum, respectively. The increased-dose group exhibited values of 7.9, 6.9, and 9.2 ?g/ml at the same three time points. Although LPV exposure was significantly higher in the increased-dose group, the standard dose produced therapeutic levels of LPV against wild-type virus in all adherent participants, except one patient in the third trimester; 50%, 37.5%, and 25%, and 0%, 15%, and 0% of the participants in the standard- and increased-dose groups failed to achieve therapeutic levels against resistant viruses during the second and third trimesters and after childbirth, respectively. After 12 weeks of treatment and after childbirth, all adherent participants achieved undetectable HIV viral loads, and their babies (49/54) were uninfected. No serious drug-related adverse events were observed. We conclude that the standard dose is appropriate for use during pregnancy and that an increased dose may be necessary for women harboring resistant HIV. (This study has been registered at under registration no. NCT00605098.) PMID:24614377

Estrela, Rita de Cássia Elias; Veloso, Valdiléa Gonçalves; Cattani, Vitória Berg; Yanavich, Carolyn; Velasque, Luciane; Torres, Thiago Silva; Marins, Luana Monteiro Spindola; Pilotto, José Henrique; João, Esaú Custódio; Gonçalves, José Carlos Saraiva; Grinsztejn, Beatriz



Clinical trial on the efficacy and safety of different diclofenac formulations: Multipleunit formulations compared to enteric coated tablets in patients with activated osteoarthritis  

Microsoft Academic Search

—This double-blind, randomised, multicentre study investigated the efficacy and safety of two different dosages of a diclofenac\\u000a sodium dual release capsule (150 mg or 75 mg once daily) in comparison to a standard treatment with enteric coated tablets\\u000a (50 mg t.i.d.) and placebo in patients with activated osteoarthritis. Pain relief as the main efficacy variable was measured\\u000a through 24 hours

W. Schmitt; K. Walter; H. J. Kurth



Preparation of controlled release tablets of TA-5707F with wax matrix type and their in vivo evaluation in beagle dogs.  


Studies on controlled release dosage forms were conducted by using waxy materials for a newly developed anti-allergy drug, 6-methyl-N-(1H-tetrazol-5-yl)-2-pyridinecarboxamide (TA-5707F), which is not maintained at an effective level in blood for a long duration. Four kinds of tablets were prepared by changing the amount of hydrogenated oil (K3 wax) and polyethyleneglycol-6000 in the tablets. Then, they were administered orally to beagle dogs, and the TA-5707F concentration in the plasma was determined by a HPLC method. The pharmacokinetic parameters were estimated and compared with the results of the in vitro dissolution test determined by the JP paddle method and by the disintegration method. The linearity between the in vivo mean dissolution time (MDT) and in vitro MDT was good in both in vitro dissolution methods. However, the MDTs obtained by the disintegration method were one-third of the in vivo MDT, while those obtained by the paddle methods were 3 times higher. This suggests that both the diffusion of TA-5707F through the waxy matrix and the erosion of the wax matrix caused by the gastrointestinal (GI) tract mobility contributed to the in vivo dissolution mechanism. The blood levels were very low when the tablet was administered after giving food. The prolongation of resident time in the stomach and the low solubility of TA-5707F in an acidic medium seemed to be related to the phenomena. By the depression of GI motility using propantheline bromide, the blood levels could be markedly prolonged and the area under the plasma concentration-time curve (AUC) increased 1.3 times. PMID:7581255

Yamakita, H; Maejima, T; Osawa, T



Development and characterization of buccoadhesive nifedipine tablets  

Microsoft Academic Search

The buccoadhesive controlled-release tablets for delivery of nifedipine were prepared by direct compression of carboxymethyl cellulose (CMC) with carbomer (CP), which showed superior bioadhesion properties compared to polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), hydroxypropylmethyl cellulose (HPMC), and acacia in a modified tensiometry method in vitro. The tablets containing 30mg of nifedipine and various amounts of CMC and CP showed a zero-order

J. Varshosaz; Z. Dehghan



Formulation and evaluation of fast dissolving tablets of cinnarizine using superdisintegrant blends and subliming material  

PubMed Central

The aim of this investigation was to develop fast dissolving tablet of cinnarizine. A combination of super disintegrants, i.e., sodium starch glycolate (SSG) and crosscarmellose sodium (CCS) were used along with camphor as a subliming material. An optimized concentration of camphor was added to aid the porosity of the tablet. A 32 full factorial design was applied to investigate the combined effect of two formulation variables: Amount of SSG and CCS. Infrared (IR) spectroscopy was performed to identify the physicochemical interaction between drug and polymer. IR spectroscopy showed that there is no interaction of drug with polymer. In the present study, direct compression was used to prepare the tablets. The powder mixtures were compressed into tablet using flat face multi punch tablet machine. Camphor was sublimed from the tablet by exposing the tablet to vacuum drier at 60°C for 12 hours. All the formulations were evaluated for their characteristics such as average weight, hardness, wetting time, friability, content uniformity, dispersion time (DT), and dissolution rate. An optimized tablet formulation (F 9) was found to have good hardness of 3.30 ± 0.10 kg/cm2, wetting time of 42.33 ± 4.04 seconds, DT of 34.67 ± 1.53 seconds, and cumulative drug release of not less than 99% in 16 minutes. PMID:22247895

Basu, Biswajit; Bagadiya, Abhishek; Makwana, Sagar; Vipul, Vora; Batt, Devraj; Dharamsi, Abhay



Formulation and evaluation of fast dissolving tablets of cinnarizine using superdisintegrant blends and subliming material.  


The aim of this investigation was to develop fast dissolving tablet of cinnarizine. A combination of super disintegrants, i.e., sodium starch glycolate (SSG) and crosscarmellose sodium (CCS) were used along with camphor as a subliming material. An optimized concentration of camphor was added to aid the porosity of the tablet. A 3(2) full factorial design was applied to investigate the combined effect of two formulation variables: Amount of SSG and CCS. Infrared (IR) spectroscopy was performed to identify the physicochemical interaction between drug and polymer. IR spectroscopy showed that there is no interaction of drug with polymer. In the present study, direct compression was used to prepare the tablets. The powder mixtures were compressed into tablet using flat face multi punch tablet machine. Camphor was sublimed from the tablet by exposing the tablet to vacuum drier at 60°C for 12 hours. All the formulations were evaluated for their characteristics such as average weight, hardness, wetting time, friability, content uniformity, dispersion time (DT), and dissolution rate. An optimized tablet formulation (F 9) was found to have good hardness of 3.30 ± 0.10 kg/cm(2), wetting time of 42.33 ± 4.04 seconds, DT of 34.67 ± 1.53 seconds, and cumulative drug release of not less than 99% in 16 minutes. PMID:22247895

Basu, Biswajit; Bagadiya, Abhishek; Makwana, Sagar; Vipul, Vora; Batt, Devraj; Dharamsi, Abhay



Application and Characterization of Gum from Bombax buonopozense Calyxesas an Excipient in Tablet Formulation  

PubMed Central

This study was undertaken to explore gum from Bombax buonopozense calyxes as a binding agent in formulation of immediate release dosage forms using wet granulation method. The granules were characterized to assess the flow and compression properties and when compressed, non-compendial and compendial tests were undertaken to assess the tablet properties for tablets prepared with bombax gum in comparison with those prepared with tragacanth and acacia gums. Granules prepared with bombax exhibited good flow and compressible properties with angle of repose 28.60°, Carr’s compressibility of 21.30% and Hausner’s quotient of 1.27. The tablets were hard, but did not disintegrate after one hour. Furthermore, only 52.5% of paracetamol was released after one hour. The drug release profile followed zero order kinetics. Tablets prepared with bombax gum have the potential to deliver drugs in a controlled manner over a prolonged period at a constant rate. PMID:24300296

Ngwuluka, Ndidi C.; Kyari, Jehu; Taplong, John; Uwaezuoke, Onyinye J.



Sustained Release Tablets Containing Soluble Polymethacrylates: Comparison with Tableted Polymethacrylate IPEC Polymers  

Microsoft Academic Search

The objective of this study was to compare a novel sustained release tablet formulation that has the potential to be used\\u000a for drugs of different physicochemical properties using a binary mixture of polymethacrylate polymers in their salt forms\\u000a with the polymethacrylate interpolyelectrolyte complex (IPEC) tablets in terms of drug release and compactness. Also, we aimed\\u000a to compare this formulation with

Wasfy M. Obeidat; Alaa H. Abuznait; Al-Sayed A. Sallam



Optimization of disintegration behavior of biodegradable poly (hydroxy butanoic acid) copolymer mulch films in soil environment  

NASA Astrophysics Data System (ADS)

Biodegradation of polymeric films used for mulch film applications in agriculture not only eliminates problems of sorting out and disposal of plastics films, but also ensures increased yields in crop growth and cost reduction. One such polymer which is completely biodegradable in the soil is poly 3-hydroxy butanoic acid copolymer, which is a promising alternative to non-biodegradable incumbent polyethylene mulch films. The purpose of mulch film made of poly 3-hydroxy butanoic acid copolymers is to sustain itself during the crop growth and disintegrate and eventually biodegrade back to nature after the crop cycle is over. The disintegration phase of the biodegradation process was evaluated for poly 3-hydroxy butanoic acid copolymer incorporated with no additive, antimicrobial additives, varying amount of crystallinities, another biodegradable polymer, and in different soils, with or without varying soil moisture content. The tools used for quantification were weight loss and visual observation. The test method was standardized using repeatability tests. The onset of disintegration was optimized with addition of right anti-microbial additives, higher crystallinity of film, blending with other biodegradable polymers, compared to virgin poly 3-hydroxy butanoic acid copolymer film. The onset of disintegration time was reduced when soil moisture content was reduced. After the onset of disintegration, the polymer film was physically and mechanically deteriorated, withering away in soil, which is possible to tailor with the crop growth cycle.

Mahajan, Viabhav


Formulation, characterization and physicochemical evaluation of amoxicillin effervescent tablets  

PubMed Central

Background: Amoxicillin is a semisynthetic antibiotic, which is used as an antimicrobial drug. This study was designed to formulate amoxicillin effervescent tablets, aimed at improved patient compliance and increased drug stability. Materials and Methods: In this study, nine effervescent tablet formulations were prepared from amoxicillin trihydrate. The effervescent base was comprised of various amounts of citric acid and sodium bicarbonate. Powders and granules were evaluated for their particle size, bulk density, tapped density, compressibility index, Hausner's ratio and angle of repose. The effervescent tablets were then prepared from powders and granules of acceptable quality by direct compression and fusion methods. The tablets were evaluated for weight variation, friability, pH of solution, carbon dioxide (CO2) content, hardness, effervescence time, thickness, assay, content uniformity, water content and equilibrium moisture content. Results: The results indicated better flowability of granules prepared by fusion method as compared with the direct compression. The percent weight variations of tablets were within the acceptable limit of 0.5%. The friability was less than 1% in all formulations. The solution pH of tablets prepared by direct compression and fusion methods ranged from 4.55 to 5.74 and 4.74-5.84, respectively. The CO2 amounts generated by of fusion method tablets were smaller as compared to the direct compression method. The hardness of tablets was 40.66-56 for direct compression method and 60.6-74.6 for fusion method. The tablets produced by the fusion method had a larger thickness and lower water content than tablets produced by direct compression method. Conclusion: Tablets prepared by the fusion method exhibited superior pre- and post-compression characteristics as compared to tablets prepared by direct compression method. PMID:25371866

Aslani, Abolfazl; Sharifian, Tahereh



Modes of Disintegration of Solid Foods in Simulated Gastric Environment  

PubMed Central

A model stomach system was used to investigate disintegration of various foods in simulated gastric environment. Food disintegration modes and typical disintegration profiles are summarized in this paper. Mechanisms contributing to the disintegration kinetics of different foods were investigated as related to acidity, temperature, and enzymatic effect on the texture and changes in microstructure. Food disintegration was dominated by either fragmentation or erosion, depending on the physical forces acting on food and the cohesive force within the food matrix. The internal cohesive forces changed during digestion as a result of water penetration and acidic and enzymatic hydrolysis. When erosion was dominant, the disintegration data (weight retention vs. disintegration time) may be expressed with exponential, sigmoidal, and delayed-sigmoidal profiles. The different profiles are the result of competition among the rates of water absorption, texture softening, and erosion. A linear-exponential equation was used to describe the different disintegration curves with good fit. Acidity and temperature of gastric juice showed a synergistic effect on carrot softening, while pepsin was the key factor in disintegrating high-protein foods. A study of the change of carrot microstructure during digestion indicated that degradation of the pectin and cell wall was responsible for texture softening that contributed to the sigmoidal profile of carrot disintegration. PMID:20401314

Kong, Fanbin



Tablet Splitting: A Risky Practice  


... practice of splitting tablets, the Food and Drug Administration (FDA), the American Medical Association, and other medical organizations advise against it unless it's specified in the drug's labeling. Tablet splitting often involves buying higher strength tablets and then breaking the tablets in ...


Development and stability evaluation of enteric coated Diclofenac sodium tablets using Sureteric.  


This study was aimed to develop a stable enteric coated diclofenac sodium tablets using Sureteic without a subcoating layer. Diclofenac uncoated tablets were developed and manufactured through the non direct compression process. Sureteric white aqueous coating dispersion was used as enteric coating material. Sureteric is a special mixture of Polyvinyl Acetate Phthalate (Phthalavin (R), PVAP), plasticizers and other ingredients in a suitable optimized dry powder formulation. The obtained enteric coated tablets were subjected to disintegration and no sign of cracking was observed when they placed in a hydrochloric solution at pH 1.2, but they were completely disintegrated within 10 minutes when they putted in buffered solution at pH6.8. Dissolution test was also conducted by placing tablets in 0.1 M HCl for 2 hours and then 1 hour in phosphate buffer at pH 6.8. Less than 0.9% of drug was released in the acidic phase and up to 97% in the basic medium. These results show that Sureteric can be successfully used to produce diclofenac sodium enteric coated tablets in order to prevent its release in the stomach and facilitate immediate release of the drug in the duodenum. These findings suggest that aqueous enteric coating with Sureteric system is an easy and economical approach for preparing stable diclofenac sodium enteric coat without the use of a subcoating layer. PMID:22186310

Zaid, Abdel Naser



Comparison between ozone and ultrasound disintegration on sludge anaerobic digestion.  


This paper deals with the comparison of ultrasound (mechanical) and ozone (chemical) pre-treatment on the performances of excess sludge semi-continuous digestion. Sludge solubilisation has been investigated by varying specific energy input. For each pre-treatment, long anaerobic digestion tests were carried out by two parallel digesters: one reactor, as control unit, was fed with untreated waste activated sludge, and the other one was fed with disintegrated sludge. To evaluate and compare the efficacy of both pre-treatments, the specific energy was maintained approximately the same. The digestion tests were carried out to investigate the feasibility of anaerobic digestion performance (total biogas production, volatile solids removal, sludge dewaterability) and to assess the heat balance. Results obtained from the digestion of sonicated sludge at 4% disintegration degree (? 2500 kJ/kg TS) showed that the ultrasound pre-treatment may be effective both in increasing VS destruction (+19%) and cumulative biogas production (+26%). On the contrary, the digestion test with ozonized sludge (ozone dose of 0.05 g O(3)/g TS corresponding to ? 2000 kJ/kg TS) did not indicate a significant improvement on the digestion performances. By doubling the ozone dose an improvement in the organics removal and cumulative biogas production was observed. Relevant differences in terms of colloidal charge and filterability were discussed. PMID:20719427

Braguglia, C M; Gianico, A; Mininni, G



Influence of Microwave Application on Disintegration of Sodium Hydrogen Carbonate in Water  

Microsoft Academic Search

The existence of microwave effects was reexamined for atemperature-sensitive inorganic reaction, the disintegration of sodiumhydrogen carbonate in water, for which the microwave nonthermaleffects have been previously reported. Comparative experimental testswere executed for microwave- and conventional infrared-heatedreactions, with their thermal conditions and apparatus being carefullymade similar. Their standard deviations in conversion were observed torange between 2 and 6%, showing that there

Jong Yeol Jeon; Hee Young Kim



Integration of Trade and Disintegration of Production in the Global Economy  

Microsoft Academic Search

The last few decades have seen a spectacular integration of the global economy through trade. The rising integration of world markets has brought with it a disintegration of the production process, however, in which manufacturing or services activities done abroad are combined with those performed at home. The author compares several different measures of foreign outsourcing and argues that they

Robert C. Feenstra



Continuous twin screw granulation: influence of process variables on granule and tablet quality.  


The aim of the current study was to screen theophylline (125 mg) tablets manufactured via twin screw granulation in order to improve process understanding and knowledge of process variables that determine granule and tablet quality. A premix of theophylline anhydrate, ?-lactose monohydrate and PVP (ratio: 30/67.5/2.5,w/w) was granulated with demineralized water. Experiments were done using the high-shear wet granulation module (based on twin screw granulation) of the ConsiGma™-25 unit (a continuous tablet manufacturing system) for particle size enlargement. After drying, granules were compressed using a MODUL™ P tablet press (compression force: 10 kN, tablet diameter: 12 mm). Using a D-optimal experimental design, the effect of several process variables (throughput (10-25 kg/h), screw speed (600-950 rpm), screw configuration (number (2, 4, 6 and 12) and angle (30°, 60° and 90°) of kneading elements), barrel temperature (25-40°C) and method of binder addition (dry versus wet)) on the granulation process (torque and temperature increase in barrel wall), granule (particle size distribution, friability and flowability) and tablet (tensile strength, porosity, friability, disintegration time and dissolution) quality was evaluated. The results showed that the quality of granules and tablets can be optimized by adjusting specific process variables (number of kneading elements, barrel temperature and binder addition method) during a granulation process using a continuous twin screw granulator. PMID:22687571

Vercruysse, J; Córdoba Díaz, D; Peeters, E; Fonteyne, M; Delaet, U; Van Assche, I; De Beer, T; Remon, J P; Vervaet, C



Novel mesalamine-loaded beads in tablets for delayed release of drug to the colon.  


Novel 'beads-in-a-tablet' formulations (total weight ?740-780?mg) have been prepared that meet USP 31 requirements for Delayed Release of mesalamine. Several methods are presented that overcome breakage of beads during tablet compaction were explored. Bead formulations comprise a combination of extrusion and spheronization to produce a relatively high drug load (80%), followed by coating (25%) with a colonic-targeted drug release polymer (polymethacrylates, Eudragit(®) S100), overcoated (3%) with hydroxypropyl methylcellulose (Opadry(®)) to improve bead binding and compactability, and using 20% coat of lactose/sodium starch glycolate (Explotab(®)) as binder/disintegrant/cushioning agent, thus allowing a sufficiently thick coating to be uniform and without being broken during tablet compaction. Then, the aforementioned beads were compressed into tablets at 1500 pounds of pressure containing 400?mg of mesalamine, and finally coating the compressed tablets with Surelease(®) (ethylcellulose):Opadry(®)?=?1:0.5 ranging from 1.5-2.5% weight gain; the resulting tablets met USP 31 dissolution requirements for delayed release tablets. PMID:20923254

Nguyen, Chien; Christensen, J Mark; Ayres, James W



Risedronate-loaded Eudragit S100 microparticles formulated into tablets.  


Risedronate, an anti-osteoporotic drug, is associated with low patient compliance due to the upper gastrointestinal side-effects and stringent dosing regimes. This study aimed to prepare and characterize risedronate-loaded Eudragit® S100 microparticles and develop a final dosage form by the compression of microparticles using direct tableting excipients. Microparticles were prepared by spray-drying and presented yield of 54%, encapsulation efficiency higher than 90%, mean diameter of 3.3?µm, moisture content around 8% and exhibited spherical shape and poor flowability. At pH 1.2, 23% of risedronate was released from microparticles in 120?min, while at pH 6.8 the drug took 90?min to reach 99.5%. Microparticles were compressed into tablets using microcrystalline cellulose, magnesium stearate, colloidal silicon dioxide and 2 polyvinylpyrrolidone concentrations (5% and 15%). Tablets presented low variations in weight, thickness and drug content. Besides, the formulations showed sufficient hardness, low friability and disintegrated in less than 15 min. In acid medium, no more than 16% of the drug was released in 120?min, while in intestinal medium the formulations prolonged the risedronate release for 240?min. Finally, the developed tableted microparticles can be considered a promising dosage form for oral risedronate administration. PMID:23506303

Velasquez, Aline A; Mattiazzi, Juliane; Ferreira, Luana M; Pohlmann, Lauren; Silva, Cristiane B; Rolim, Clarice M B; Cruz, Letícia



The chemical and pharmaceutical equivalence of sulphadoxine/pyrimethamine tablets sold on the Tanzanian market.  


This study investigated chemical and pharmaceutical equivalence of 11 brands of pyrimethamine-sulphadoxine combination tablets sold on the Tanzanian market. Physical and chemical tests were performed for all the 11 brands. These tests included hardness test, friability, disintegration, dissolution, weight uniformity and assay for the active components. All the brands passed all the quality specifications of the United States Pharmacopoeia (USP) and British Pharmacopoeia (BP) in terms of hardness, friability, disintegration, assay and dissolution test, except for three brands that failed the hardness, disintegration or friability tests. One brand failed both the hardness and disintegration test; one failed the hardness test, whereas another one failed the friability test. The percentage content of pyrimethamine in the brands was in the range of 91.04-100.20% whereas that of sulphadoxine ranged from 91.53% to 99.88%. There were no major differences between the different brands of tablets containing pyrimethamine and sulphadoxine and the innovator product (Fansidar), and all brands were physically and chemically equivalent. The results indicate that the post-market surveillance and registration process in Tanzania is having an impact on product quality as there was no brand which could be considered of very poor quality. Impurity profiling of all the locally produced brands indicated that they all contained the same sulphadoxine impurity, which was absent in the innovator product, suggesting a common source of generic raw material. PMID:16336290

Hebron, Y; Tettey, J N A; Pournamdari, M; Watson, D G



Microstructural investigation of tablet compaction and tablet pharmacological properties  

E-print Network

In current tablet manufacturing processes, there is a knowledge gap concerning material transformation and the subsequent impact on tablet properties; this gap presents a barrier to rational formulation / process design. ...

Mao, Kangyi



Development and characterization of buccoadhesive nifedipine tablets.  


The buccoadhesive controlled-release tablets for delivery of nifedipine were prepared by direct compression of carboxymethyl cellulose (CMC) with carbomer (CP), which showed superior bioadhesion properties compared to polyvinylpyrrolidone (PVP), polyvinyl alcohol (PVA), hydroxypropylmethyl cellulose (HPMC), and acacia in a modified tensiometry method in vitro. The tablets containing 30mg of nifedipine and various amounts of CMC and CP showed a zero-order drug release kinetic. The adhesion force was significantly affected by the mixing ratio of CP:CMC in the tablets. The weakest and highest adhesion force was observed at the mixing ratios of 1:0 and 8:2 of CP:CMC, respectively. The tablets containing 15% CMC and 35% CP adhered for over 8h to the upper gums of six healthy human volunteers. These tablets released about 56% of the loaded drug after 8h in vivo with a rate of 2.17h(-1) and were perfectly tolerated, while they released about 100% of their content after the same time with a rate of 3.49h(-1) in vitro. A good correlation (r(2)=0.989) was observed between drug-released in vitro and in vivo. PMID:12191683

Varshosaz, J; Dehghan, Z



Preparation and In Vitro/In Vivo Characterization of Porous Sublingual Tablets Containing Ternary Kneaded Solid System of Vinpocetine with ?-Cyclodextrin and Hydroxy Acid  

PubMed Central

The demand for sublingual tablets has been growing during the previous decades especially for drugs with extensive hepatic first-pass metabolism. Vinpocetine, a widely used neurotropic agent, has low oral bioavailability due to its poor aqueous solubility and marked first-pass metabolism. Accordingly, the aim of this work was to develop tablets for the sublingual delivery of vinpocetine. Initially, the feasibility of improving vinpocetine’s poor aqueous solubility by preparing kneaded solid systems of the drug with ?-Cyclodextrin and hydroxy acids (citric acid and tartaric acid) was assessed. The solid system with improved solubility and dissolution properties was incorporated into porous tablets that rapidly disintegrate permitting fast release of vinpocetine into the sublingual cavity. The pores were induced into these tablets by directly compressing the tablets’ excipients with a sublimable material, either camphor or menthol, which was eventually sublimated leaving pores. The obtained results demonstrated that the tablets prepared using camphor attained sufficient mechanical strength for practical use together with rapid disintegration and dissolution. In vivo absorption study performed in rabbits indicated that the sublingual administration of the proposed porous tablets containing vinpocetine solid system with ?-Cyclodextrin and tartaric acid could be useful for therapeutic application. PMID:21179352

Aburahma, Mona H.; El-Laithy, Hanan M.; Hamza, Yassin El-Said



Tabletability assessment of conventional formulations containing Vitamin E tocopheryl polyethylene glycol succinate.  


Vitamin E tocopheryl polyethylene glycol succinate (TPGS) is known to enhance the bioavailability of poorly water-soluble drugs via solubility and permeability enhancement. Few studies have evaluated feasibility of formulating TPGS in conventional solid dosage forms such as tablets due to processing challenges resulting from its waxy nature and low melting point (approximately 37 degrees C). The objective of this study is to systematically investigate the tabletability of conventional high shear wet granulation (WG) formulations incorporated with Vitamin E TPGS. Impact of critical formulation variables such as levels of TPGS, hydroxypropyl cellulose (binder) and Prosolv (extragranular filler) on product quality attributes was studied using a full factorial experimental design. The potential influence of temperature elevation during processing was assessed through a heated die fitted onto a compaction simulator. Bilayer tabletability of the TPGS formulation was also assessed in combination with a secondary non-TPGS formulation. TPGS levels significantly impacted tensile strength (TS), disintegration time and dissolution. Heat sensitivity studies indicated that TS reduction upon exposure to heat was minimized by higher levels of extragranular fillers. Acceptable interfacial strength of bilayer tablets was achieved and tablets could be coated without the need for hydroalcoholic solutions. The study demonstrates preliminary feasibility to develop monolithic and bilayer coated tablet formulations containing up to 10% (w/w) TPGS for the given compound and drug load. Further studies are required to validate these findings at larger scales. PMID:20083178

Jin, Feiyan; Tatavarti, Aditya



Comparative efficacy of a spot-on formulation containing emodepside and praziquantel (Profender ®, Bayer) and praziquantel and pyrantel oral tablets (Drontal ® for Cats) against experimental Ancylostoma ceylanicum infections in cats.  


Ancylostoma ceylanicum is a common zoonotic hookworm of dogs and cats throughout Asia and has also been reported to occur within the Australasian region. The aim of this study to was to determine the efficacy of a spot-on formulation containing emodepside and praziquantel (Profender(®), Bayer) and praziquantel and pyrantel oral tablets (Drontal(®) for Cats, Bayer) against experimental A. ceylanicum infections in cats. Twenty-four kittens were each subcutaneously injected with 100 infective third-stage larvae of A. ceylanicum. Kittens were stratified by egg count and randomly allocated equally into control and two treatment groups. The first group were treated with emodepside 2.1%/praziquantel 8.6% (Profender®, Bayer) at the recommended label dose. The second group was treated with 80 mg pyrantel and 20mg praziquantel (Drontal(®) for Cats, Bayer) at the recommended label dose. The kittens in the control group were not treated. Egg counts were performed daily until the end of the study period and compared for the treated and control groups. No eggs were detected in the treated group of kittens within 4 days of treatment and faecal samples from this group remained negative throughout the rest of the study, resulting in a treatment efficacy (egg reduction) of 100% (P<0.0001). The egg counts remained high (993 ± 666 epg) in the untreated control group for the rest of the study period. This study demonstrated that both combination products containing topical emodepside/praziquantel (Profender(®), Bayer) and praziquantel/pyrantel oral tablets (Drontal(®) for Cats, Bayer) given at the recommended dose is highly effective against infection with A. ceylanicum in cats. PMID:23026558

Taweethavonsawat, Piyanan; Chungpivat, Sudchit; Watanapongchati, Supoj; Traub, Rebecca J; Schaper, Roland



Pharmacokinetics and relative bioavailability of ofloxacin tablets in 12 healthy volunteers.  


Single oral dose of tablet A (Daiichi Pharmaceutical Co Ltd, Japan) and B (Jining Pharmaceutical Factory, Shandong, China) of 300 mg ofloxacin (Ofl) were given to 12 Chinese healthy male volunteers in an open, randomized crossover study. Drug concentrations in serum and urine were assayed by HPLC and partial least squares spectrophotometric method, respectively. The serum concentration-time course after medication conformed to a 2-compartment open model with a first order absorption. Pharmacokinetic parameters after tablet B did not differ significantly from the corresponding values after tablet A. The bioavailability of tablet B was comparable to that of tablet A. PMID:1598824

Diao, Y; Li, L; Zhou, G H; Cheng, Y



[Tablets and tablet production - with special reference to Icelandic conditions].  


Modern tablet compression was instituted in England in 1844 by William Brockedon (1787-1854). The first tablets made according to Brockedon´s procedures contained watersoluble salts and were most likely compressed without expedients. In USA a watershed occurred around 1887 when starch (amylum maydis) was introduced to disperse tablets in aqueous milieu in order to corroborate bioavailability of drugs in the almentary canal. About the same time great advances in tablet production were introduced by the British firm Burroughs Wellcome and Co. In Denmark on the other hand tablet production remained on low scale until after 1920. As Icelandic pharmacies and drug firms modelled themselves mostly upon Danish firms tablet production was first instituted in Iceland around 1930. The first tablet machines in Iceland were hand-driven. More efficent machines came after 1945. Around 1960 three sizeable tablet producers were in Iceland; now there is only one. Numbers of individual tablet species (generic and proprietary) on the market rose from less than 10 in 1913 to 500 in 1965, with wide variations in numbers in between. Tablets have not wiped out other medicinal forms for peroral use but most new peroral drugs have been marketed in the form of tablets during the last decades. PMID:23695970

Skaftason, Jóhannes F; Jóhannesson, Thorkell



Suitability of ?-carrageenan pellets for the formulation of multiparticulate tablets with modified release.  


?-Carrageenan is a novel pelletisation aid with high formulation robustness and quick disintegration leading to fast drug release unlike the matrix-like release from non-disintegrating microcrystalline cellulose pellets. Compression of pellets into tablets is cost effective. The feasibility of formulating multiparticulate tablets with coated ?-carrageenan pellets was investigated. Pellets containing a highly soluble drug in acid, namely bisacodyl and ?-carrageenan or MCC as pelletisation aid were prepared, enteric coated with a mixture of Kollicoat(®) MAE 30 DP and Eudragit(®) NE 30 D and compressed using silicified microcrystalline cellulose as embedding powder. The effect of coating level, type of pellet core, compression force and punch configurations on drug release were studied. A sufficient coating thickness for ?-carrageenan pellets was necessary to obtain multiparticulate tablets with adequate resistance in the acid stage regardless of the compression pressure used. While ?-carrageenan pellets and their tablets released over 80% of the drug during the neutral stage only about 20-24% was released from MCC pellets and their tablets. The type of punches used (oblong or round) did not significantly influence the drug release from the prepared tablets. Moreover, sufficient prolonged release properties were obtained with ?-carrageenan pellets containing theophylline as a model drug and coated with Kollicoat(®) SR 30 D using Kollicoat(®) IR as pore former. A lower coating level and higher amount of pore former were needed in case of theophylline pellets formulated with MCC as pelletisation aid. The sustained release properties of both coated pellet formulations were maintained after compression at different compression pressures. PMID:21335073

Ghanam, Dima; Kleinebudde, Peter



Tablet Process Simulator  

NSDL National Science Digital Library

The North Carolina Community College System BioNetwork's interactive eLearning tools (IETs) are reusable chunks of training that can be deployed in a variety of courses or training programs. IETs are designed to enhance, not replace hands-on training. Learners are able to enter a hands-on lab experience better prepared and more confident. This particular IET is a Tablet Process Simulator in which visitors set up and run a tablet press in a virtual 3D environment. The tool requires the program to be downloaded and installed, and gives helpful installation instructions. Users will start by downloading a zip file to their computer.



CES 2011: Tablet Crazy  

ERIC Educational Resources Information Center

Ereaders are so last year. Tablets were the watchword at this year's annual Consumer Electronics Show (CES) in Las Vegas, January 6-9. This year, the show set new records, with some 2700 companies from around the world exhibiting at the multiple exhibition halls and 30,000 attendees gawking at the products. What did they see? There were still some…

Rapp, David



Development and evaluation of fixed dose bi therapy sublingual tablets for treatment stress hypertension and anxiety  

PubMed Central

Objective: A stress induced rise in the blood pressure. Some believe that patients with hypertension are characterized by a generalized state of increased anxiety. Aim: The purpose of this study is to prepare a fixed dose bi therapy using bisoprolol hemifumarate (BH) as antihypertensive drug and buspirone hydrochloride (BuHCl) as anxiolytic drug, which can be used to treat both diseases concomitantly. Using sublingual tablets is hopeful to improve the BuHCl poor oral bioavailability and to facilitate administration to patients experiencing problems with swallowing. Materials and Methods: A total of 5mg BH and 10mg BuHCl were selected based on compatibility study. A 3×22 full factorial design was adopted for the optimization of the tablets prepared by direct compression method. The effects of the filler type, the binder molecular weight, and the binder type were studied. The prepared formulae were evaluated according to their physical characters as hardness, friability, disintegration time (new modified method and in vivo disintegration time) and wetting properties. In vitro drugs dissolute, permeation through the buccal mucosa and the effect of storage were analyzed by a new valid high pressure liquid chromatography (HPLC) method. Bioavailability study of the selected formula study was carried out and followed by the clinical. Results: The optimized tablet formulation showed accepted average weight, hardness, wetting time, friability, content uniformity, disintegration time (less than 3 min). Maximum drug release could be achieved with in 10 min. In addition enhancing drug permeation through the buccal mucosa and, the maximum concentration of the drug that reached the blood was in the first 10 min which means a rapid onset of action and improved the extent of both drug's absorption. Conclusion: The results revealed that sublingual (F6) tablets containing both drugs would maintain rapid onset of action, and increase bioavailability. BuHCl with BH can be attributed to the marked decline in DBP and SBP. That led to a reduction in the MAP. PMID:24082695

El-Nabarawi, Mohamed A.; Tayel, Saadia A.; Soliman, Nadia A.; Abo Enin, Hadel A.



Drug release behaviour from methyl methacrylate-starch matrix tablets: effect of polymer moisture content.  


The aim of this work was to study the effect of the initial moisture content of the polymer on the tabletting and drug release behaviour of controlled release inert matrices elaborated with methyl methacrylate (MMA)-starch copolymers. The copolymers, obtained by free radical polymerisation and dried by two different methods (oven-drying or freeze-drying), were equilibrated at different relative humidities (0%, 25%, 50% and 75% RH) at room temperature. From these copolymers, matrix systems were directly compressed containing either a slightly water-soluble drug (anhydrous theophylline) or a freely water-soluble drug (salbutamol sulphate), and their compaction properties and in vitro dissolution profiles were evaluated. The release profiles were compared following model-independent methods, such as the Qt parameter and the similarity factor f2. Moreover, several kinetic models were employed to evaluate the possible changes in the release mechanism. For anhydrous theophylline, the initial moisture content of the copolymers did not affect the release characteristics from the inert matrices under study, and a typical Fickian diffusion mechanism was observed for the different formulations. However, in case of salbutamol sulphate, the presence of moisture might induce a fast drug dissolution, promoting the weakness of the matrix structure and hence, its partial disintegration. So, an "anomalous" mixed phenomenon of diffusion and erosion was found, influenced by the initial moisture content of the copolymer. PMID:17997292

Bravo-Osuna, I; Ferrero, C; Jiménez-Castellanos, M R



Evaluation of Three Chitin Metal Silicate Co-Precipitates as a Potential Multifunctional Single Excipient in Tablet Formulations  

PubMed Central

The performance of the novel chitin metal silicate (CMS) co-precipitates as a single multifunctional excipient in tablet formulation using direct compression and wet granulation methods is evaluated. The neutral, acidic, and basic drugs Spironolactone (SPL), ibuprofen (IBU) and metronidazole (MET), respectively, were used as model drugs. Commercial Aldactone®, Fleximex® and Dumazole® tablets containing SPL, IBU and MET, respectively, and tablets made using Avicel® 200, were used in the study for comparison purposes. Tablets of acceptable crushing strength (>40 N) were obtained using CMS. The friability values for all tablets were well below the maximum 1% USP tolerance limit. CMS produced superdisintegrating tablets (disintegration time < 1 min) with the three model drugs. Regarding the dissolution rate, the sequence was as follow: CMS > Fleximex® > Avicel® 200, CMS > Avicel® 200 > Dumazole® and Aldactone® > Avicel® 200 > CMS for IBU, MET and SPL, respectively. Compressional properties of formulations were analyzed using density measurements and the compression Kawakita equation as assessment parameters. On the basis of DSC results, CMS co precipitates were found to be compatible with the tested drugs. Conclusively, the CMS co-precipitates have the potential to be used as filler, binder, and superdisintegrant, all-in-one, in the design of tablets by the direct compression as well as wet granulation methods. PMID:20559493

Hamid, Rana Al-Shaikh; Al-Akayleh, Faisal; Shubair, Mohammad; Rashid, Iyad; Remawi, Mayyas Al; Badwan, Adnan



Multiple-layer compression-coated tablets: formulation and humidity studies of novel chewable amoxicillin/clavulanate tablet formulations.  


The purpose of this study was to produce novel multiple-layer, compression-coated, chewable tablet formulations containing amoxicillin trihydrate, and clavulanic acid as potassium clavulanate, and to test in vitro dissolution characteristics and the effect of humidity stability compared to Augmentin chewable tablets as a reference. Double- and triple-layer tablets were manufactured on a laboratory scale by multiple-layer dry compression, and dissolution profiles of both active ingredients were determined. Tablets were subjected to stability evaluation in laboratory-scale humidity tanks maintained at constant humidity. Assay of content was determined by HPLC or UV spectroscopy. Physical characteristics of the powder mixture, such as angle of repose, and of tablets for hardness and friability, were also determined. Chewable tablets showed similar dissolution profiles in vitro for both active ingredients, compared to the marketed reference, Augmentin. The stability of clavulanic acid, but not amoxicillin, was increased in the novel triple or bilayer formulation. The tablets showed suitable friability, hardness, and angle of repose for starting materials to suggest that industrial scale-up is feasible. This approach to formulation of drugs containing multiple or moisture-sensitive ingredients has been shown to increase the stability of the central core drug without changing the dissolution pattern of the active ingredients. This formulation is expected to be bioequivalent in vivo based on these in vitro results. PMID:9876520

Wardrop, J; Jaber, A B; Ayres, J W



Pharmacokinetic comparison of oral solution and tablet formulations of citalopram: a single-dose, randomized, crossover study  

Microsoft Academic Search

Background: Citalopram tablets fulfill most dosing needs in the treatment of depression, but some patients may have difficulty swallowing tablets and thus may be less likely to comply with their medication regimen. A liquid formulation of citalopram could be beneficial for such patients.Objective: This study was undertaken to compare the pharmacokinetic profiles of oral solution and tablet formulations of citalopram

Marcelo M. Gutierrez; Wattanaporn Abramowitz



In vivo drug release from hydrophilic dextran tablets capable of forming polyion complex.  


The aim of this comparative study was to investigate the in vivo drug release property of hydrophilic dextran tablets with or without swelling in the upper gastrointestinal tract (GIT) in humans. Two kinds of theophylline (TH) tablets were prepared by direct compression from a mixture of carboxymethyldextran and [2-(diethylamino)ethyl]dextran as a matrix capable of forming polyion complex (PIC-tablet), and a mixture of low and medium molecular weight hydroxypropylcellulose as a representative hydrophilic matrix (HPC-tablet). In these tablets, in vitro drug release behaviors and saliva TH level profiles after oral administration to humans were similar to each other, indicating equivalent AUC value. The tablets were then coated with Eudragit S100, enteric-coating polymer, by a dipping method in order to reveal drug release without full swelling in the upper GIT. Although the two enteric-coated tablets showed a similar in vitro release pattern, saliva level profiles were quite different as reflected in AUC values of 16.4 and 4.68 microg h/ml for enteric-coated PIC- and enteric-coated HPC-tablet, respectively. These results demonstrated that HPC-tablet could not release sufficiently without swelling in the upper GIT. In contrast, enteric-coated PIC-tablet showed an equivalent AUC value to PIC-tablet, indicating that TH was released well even in the lower GIT. PMID:16824636

Miyazaki, Yasunori; Tanaka, Yoichi; Yakou, Shigeru; Takayama, Kozo



Preparation and in vitro/in vivo characterization of porous sublingual tablets containing ternary kneaded solid system of vinpocetine with î-cyclodextrin and hydroxy Acid.  


The demand for sublingual tablets has been growing during the previous decades especially for drugs with extensive hepatic first-pass metabolism. Vinpocetine, a widely used neurotropic agent, has low oral bioavailability due to its poor aqueous solubility and marked first-pass metabolism. Accordingly, the aim of this work was to develop tablets for the sublingual delivery of vinpocetine. Initially, the feasibility of improving vinpocetineâs poor aqueous solubility by preparing kneaded solid systems of the drug with Î-Cyclodextrin and hydroxy acids (citric acid and tartaric acid) was assessed. The solid system with improved solubility and dissolution properties was incorporated into porous tablets that rapidly disintegrate permitting fast release of vinpocetine into the sublingual cavity. The pores were induced into these tablets by directly compressing the tabletsâ excipients with a sublimable material, either camphor or menthol, which was eventually sublimated leaving pores. The obtained results demonstrated that the tablets prepared using camphor attained sufficient mechanical strength for practical use together with rapid disintegration and dissolution. In vivo absorption study performed in rabbits indicated that the sublingual administration of the proposed porous tablets containing vinpocetine solid system with Î-Cyclodextrin and tartaric acid could be useful for therapeutic application. PMID:21179352

Aburahma, Mona H; El-Laithy, Hanan M; Hamza, Yassin El-Said



A multicenter, randomized, double-blind, placebo-controlled, factorial design study to evaluate the lipid-altering efficacy and safety profile of the ezetimibe\\/simvastatin tablet compared with ezetimibe and simvastatin monotherapy in patients with primary hypercholesterolemia  

Microsoft Academic Search

Objective:The purpose of this study was to evaluate the efficacy and safety profile of ezetimibe\\/simvastatin(EZE\\/SIMVA) combination tablet, relative to ezetimibe (EZE) and simvastatin (SIMVA) monotherapy, in patients with primary hypercholesterolemia.

Harold E. Bays; Leiv Ose; Neil Fraser; Diane L. Tribble; Katherine Quinto; Robert Reyes; Amy O. Johnson-Levonas; Aditi Sapre; Steven R. Donahue



Randomized, double-blind, placebo-controlled and active-controlled study to assess the relative abuse potential of oxycodone HCl-niacin tablets compared with oxycodone alone in nondependent, recreational opioid users  

PubMed Central

Background Abuse-deterrent formulations attempt to address public health and societal concerns regarding opioid abuse. Oxycodone HCl-niacin tablets combine oxycodone HCl with niacin and functional inactive excipients to create potential barriers to oral, intranasal, and intravenous abuse. This study compared the relative abuse potential of oral immediate-release oxycodone HCl-niacin with that of oral immediate-release oxycodone HCl and placebo in nondependent, recreational opioid users. Methods Forty-nine participants received oxycodone HCl-niacin 40/240 mg and 80/480 mg, oxycodone 40 mg and 80 mg, and placebo in a randomized, double-blind, placebo-controlled and active-controlled, five-way crossover study. Primary endpoints based on a bipolar 100 mm visual analog scale for drug liking were area under effect curve (AUE0–1h, AUE0–2h, AUE0–3h), peak disliking, and effect at 0.5 hours post-dose (E0.5h). Other endpoints included take drug again assessment, overall drug liking, and pupillometry. Results There were statistically significant differences between oxycodone HCl-niacin and oxycodone HCl doses for all primary endpoints (P < 0.0001, all comparisons), suggesting reduced abuse potential with oxycodone HCl-niacin. Take drug again and overall drug liking showed greater liking of oxycodone alone. Oxycodone HCl-niacin 80/480 mg had consistently lower liking assessments than oxycodone HCl-niacin 40/240 mg, suggesting a dose-response to the aversive effects of niacin. Opioid-related adverse events were similar for equivalent oxycodone doses. The treatment-emergent adverse events most specifically associated with oxycodone HCl-niacin (ie, skin-burning sensation, warmth, and flushing) were consistent with the expected vasocutaneous effects of niacin. No serious adverse events were reported. Conclusion Oxycodone HCl-niacin tablets may, in a dose-dependent manner, decrease the potential for oral abuse of oxycodone without unexpected adverse events or clinically signifi-cant differences in safety parameters compared with oxycodone alone. Although statistically powered, the small size of the study sample and the characteristics of its participants may not be generalizable to the population that abuses prescription opioid medications. PMID:24474870

Webster, Lynn R; Rolleri, Robert L; Pixton, Glenn C; Sommerville, Kenneth W



In-line monitoring of the drug content of powder mixtures and tablets by near-infrared spectroscopy during the continuous direct compression tableting process.  


Continuous manufacturing methods offer economic and quality advantages when compared with batch manufacturing methods. In continuous manufacturing, one requires real time assurance of quality of product via the implementation of PAT tools. This study focuses on an in-line near-infrared (NIR) spectroscopic method for determining the drug content of powder mixtures and tablets during a continuous tableting process. Tablets consisting of acetaminophen (20-30%), lactose (69.07-78.93%) and magnesium stearate (0.93-1.07%) were prepared in a continuous direct compression line that consisted of two loss-in-weight feeders, one for acetaminophen and one for premixed lactose and magnesium stearate, and a continuous mixer followed by a rotary tablet press. NIR spectroscopy was applied to the continuous mixer and tablet press to perform a 100% product check at full tableting speed. The UV-spectrophotometric method was used as an off-line reference method to determine the acetaminophen content in the samples. The powder mixture and tablet samples were taken during the process for the calibration of continuous mixer and tablet press, respectively. For the continuous mixer, model creation with the PLS method yielded R-Square and RMSEC (root mean square error of calibration) values of 0.975% and 0.56%, respectively. For the tablet press, the corresponding R-Square and RMSEC values were 0.943% and 0.75%, respectively. A test run demonstrated good predictability in the estimation of the API content in the powder mixtures and tablets during the continuous tableting process. For the continuous mixer and tablet press, the RMSEP (root mean square error of prediction) values were 0.96% and 1.37%, respectively. This study demonstrates that an NIR instrument capable of fast spectra acquisition can be a valuable tool for the in-line monitoring of the continuous mixing and tableting processes. PMID:23313622

Järvinen, Kristiina; Hoehe, Wolfgang; Järvinen, Maiju; Poutiainen, Sami; Juuti, Mikko; Borchert, Sven



[Sanhuang tablets research].  


Sanhuang tablets is one of common traditional Chinese patent preparation, it has effects of clear fever, detoxifcation, dispel inflammation, purgation. It was contained in the ministerial standards of Ministry of Health in 1997, and was contained in Chinese pharmacopoeia version 1 of 2000 and 2005. Its improvement of dosage form, preparation technique, quality analysis, pharmacology and clinical usage were reviewed in this paper. PMID:17993010

Liu, Cui-zhe; Chen, Da-wei



Formulation, development, and performance evaluation of metoclopramide HCl oro-dispersible sustained release tablet.  


The present study was undertaken to develop and evaluate an oro-dispersible, sustained release tablet of metoclopramide HCl. The technology was comprised of developing sustained release microparticles, and compression of resultant microspheres into a fast dispersible tablet by direct compression. The microspheres of metoclopramide HCl were prepared by an emulsification-solvent evaporation method using ethylcellulose as the matrix polymer. The prepared microspheres were evaluated for morphology, particle size, entrapment efficiency, and in vitro drug release characteristics. Scanning electron microscopy demonstrated spherical particles with a mean diameter of 81.27 ± 5.87 ?m and the drug encapsulation efficiency was found to be 70.15 ± 3.06%. The process and formulation variables such as rotation speed, polymer concentration, and drug concentration influenced the drug encapsulation efficiency and in vitro drug release. Optimized microspheres were compressed into tablets which were comprised of metoclopramide HCl microspheres, 53% (w/v) of D-mannitol granules, 7% (w/w) of Polyplasdone XL 10, and 0.5% (w/w) of calcium stearate. The tablets demonstrated a hardness of 59 ± 3 N, friability of 0.21% and disintegration time of 27 ± 3 sec. The formulations were subjected to stability studies as per ICH guidelines and were found to be stable after a 6 month study. In vivo experiments conducted in rats demonstrated that a constant level of metoclopramide HCl in plasma could be maintained for up to 20 h at a suitable concentration for antiemetic activity. An appropriate combination of excipients made it possible to obtain orally disintegrating sustained release tablets of metoclopramide HCl using simple and conventional techniques. PMID:22076769

Kasliwal, Nikhil; Negi, Jeetendra Singh; Jugran, Vandana; Jain, Rahul



New Dissolution Method for Mesalamine Tablets and Capsules  

Microsoft Academic Search

Dissolution methods are different for extended-release mesalamine capsules (pH 7.5 only) and delayed-release tablets (pH 1.4, 6.0, and 7.2). Mesalamine is used for the treatment of ulcerative colitis. The USP methods have several drawbacks in that they do not mimic gastrointestinal tract environments; tablets are removed from vessels to change dissolution medium; and neither method has been adopted to compare

Monica C. Chuong; J. Mark Christensen; James W. Ayres


A randomised trial of glucose tablets to aid smoking cessation  

Microsoft Academic Search

Rationale Oral glucose has been found to decrease tobacco craving among abstaining smokers. One study has demon- strated an effect of glucose on short-term abstinence. There is a need to examine any long-term benefit of glucose on abstinence. Objectives To assess whether glucose tablets improve 6-month continuous abstinence rates compared with low- calorie placebo tablets. Methods Smokers attempting to stop

Robert West; Sylvia May; Andy McEwen; Hayden McRobbie; Peter Hajek; Eleni Vangeli



Photoimages and the release characteristics of lipophilic matrix tablets containing highly water-soluble potassium citrate with high drug loadings.  


Two types of the carnauba wax-based lipophilic matrix tablet using spray-dried granules (SDT) or directly compressible powdered mixtures (DCT) were prepared for sustained release. The model drug was a highly water-soluble potassium citrate and loaded about 74% of the total tablet weight. The SDT slowly eroded and disintegrated during the release study without showing sustained release when the hydrophilic excipients were added. In contrast, the DCT was more efficient for sustained release. The release rate decreased with increasing carnauba wax concentration. In particular, the sustained release rate was markedly pronounced when the lipophilic stearyl alcohol and stearic acid were combined with the carnauba wax. The surface of the intact DCT appeared to be smooth and rusty. The DCT rose to the surface from the bottom of the vessel during the release test, and numerous pores and cracks with no signs of disintegration were also observed after the release test. The release profile was dependent on the formulation composition and preparation method of the matrix tablet. Diffusion-controlled leaching through the channels of the pores and cracks of the lipophilic matrix tablet (DCT) is a key to the sustained release. PMID:17532156

Cao, Qing-Ri; Kim, Tae-Wan; Lee, Beom-Jin



Effects of disintegration on anaerobic degradation of sewage excess sludge in downflow stationary fixed film digesters.  


The effects of mechanical disintegration on anaerobic digestibility of sewage excess sludge in downflow stationary fixed film (DSFF) digesters were investigated on laboratory scale. Mechanical pretreatment using a high pressure homogenizer led to significantly enhanced concentrations of soluble proteins and carbohydrates in the feed sludge. Using DSFF digesters with two different tubular plastic media as support material it was shown that a stable digestion process could be achieved at hydraulic retention times (HRT) down to 5 days. Compared to conventional digesters at 10 d and 15 d HRT respectively, the degradation of volatile solids was enhanced up to 25%, also resulting in a higher specific biogas production. Further investigations on degradation of soluble proteins and carbohydrates showed that a slowly degradable fraction of carbohydrates was released via disintegration. Using the distribution of chain length and the concentrations of volatile fatty acids as process parameters, the dependability on the HRT and the degree of disintegration (the release of soluble COD) predominated the effects of specific surface area of the support media. PMID:11381989

Engelhart, M; Krüger, M; Kopp, J; Dichtl, N



Formulation and evaluation of time-controlled triple-concentric mefenamic acid tablets for rheumatoid arthritis.  


A triple-concentric time-controlled release mefenamic acid (MA) tablet was developed using Carbopol and Ethocel polymers. The burst dose was programed to release immediately after an ingestion of tablet to be followed by a lag period of 2-4?h, and thereafter an 8?h controlled release of MA from core tablet. Core tablets were prepared using Carbopols 971P, 974P, 71G or 907 at various concentrations. The core tablet provided a controlled release of MA and the release rate decreased with increasing polymer concentration. Highly cross-linked Carbopol 974P released MA at a faster rate compared to release from Carbopol 971P with medium degree of cross-linking. Carbopols 71G and 971P exhibited essentially similar release rates. Carbopol 907, a linear polymer, showed fastest release of MA. The extent of uptake of dissolution medium by core tablets was inversely related to the rate of release of MA from the tablets. Compression coating of core tablet with Ethocel provided the lag period to delay release of MA from core tablet. Increase in lateral coating thickness decreased MA release and increased lag period. Compression forces applied during compression coating with Ethocel for lag period, and immediate-release MA coating for burst release did not affect the integrity of core tablet. PMID:23611159

Patel, Pooja; Madan, Parshotam; Lin, Senshang



Pharmacokinetics of Buspirone Extended-Release Tablets: A Single-Dose Study  

Microsoft Academic Search

The objective of this study is to evaluate the absorption of buspirone and its biotransformation to 1-(2-pyrimidinyl) piperazine (1-PP) from two different extended-release (ER) formulations of buspirone HCl tablets (12-hour and 24-hour in vitro release) and from a commercially available immediate-release (IR) tablet. A single dose of the 30 mg ER tablets was compared with two doses of the 15

Adel Sakr; Mahalaxmi Andheria



An osmotic bioequivalent nifedipine tablet  

Microsoft Academic Search

A new osmotic nifedipine tablet with a controlled release profile of 24 hours, was developed. It is composed of a core containing nifedipine, a polymeric membrane and a laser drilled orifice to allow the release of the drug. The aim of the study was to assess the bioequivalency between the osmotic nifedipine tablet and the innovator Procardia® XL (nifedipine extended

E. C. Feleder; M. Befumo; M. A. Ricci; M. A. Coppari; J. Faour



Review of bilayer tablet technology.  


Therapeutic strategies based on oral delivery of bilayer (and multilayer) tablets are gaining more acceptance among brand and generic products due to a confluence of factors including advanced delivery strategies, patient compliance and combination therapy. Successful manufacturing of these ever more complex systems needs to overcome a series of challenges from formulation design to tablet press monitoring and control. This article provides an overview of the state-of-the-art of bilayer tablet technology, highlighting the main benefits of this type of oral dosage forms while providing a description of current challenges and advances toward improving manufacturing practices and product quality. Several aspects relevant to bilayer tablet manufacturing are addressed including material properties, lubrication, layer ordering, layer thickness, layer weight control, as well as first and final compression forces. A section is also devoted to bilayer tablet characterization that present additional complexities associated with interfaces between layers. The available features of the manufacturing equipment for bilayer tablet production are also described indicating the different strategies for sensing and controls offered by bilayer tablet press manufacturers. Finally, a roadmap for bilayer tablet manufacturing is advanced as a guideline to formulation design and selection of process parameters and equipment. PMID:24370841

Abebe, Admassu; Akseli, Ilgaz; Sprockel, Omar; Kottala, Niranjan; Cuitiño, Alberto M



Novel chitosan-magnesium aluminum silicate nanocomposite film coatings for modified-release tablets.  


Chitosan (CS), a positively charged polysaccharide, and magnesium aluminum silicate (MAS), a negatively charged clay with silicate layers, can electrostatically interact to form nanocomposite films. In this study, CS-MAS nanocomposite films were evaluated for use in tablet film coating. Effects of CS-MAS ratio and coating level on water uptake and drug release from the coated tablets were investigated. Surface and film matrix morphology of the coated film and the effect of enzymes in the simulated gastro-intestinal fluid on drug release were also examined. The results demonstrated that the CS-MAS coated tablets had a rough surface and a layered matrix film, whereas a smooth surface and dense matrix film on the CS coated tablets was found. However, the CS-MAS coated tablets provided fewer film defects than the CS coated tablets. Nanocomposite formation between CS and MAS could retard swelling and erosion of CS in the composite films in acidic medium. The higher MAS ratio of the CS-MAS coated tablets gave lower water uptake and slower drug release when compared with the CS coated tablets. Moreover, the CS-MAS films on the tablets presented good stability towards enzymatic degradation in simulated intestinal fluid. The release of drug from the CS-MAS coated tablets could be modulated by varying CS-MAS ratios and coating levels. Additionally, drug solubility also influenced drug release characteristics of the CS-MAS coated tablets. These findings suggest that the CS-MAS nanocomposites displays a strong potential for use in tablet film coating intended for modifying drug release from tablets. PMID:21291977

Khunawattanakul, Wanwisa; Puttipipatkhachorn, Satit; Rades, Thomas; Pongjanyakul, Thaned



Dynamic vapor sorption properties of sodium starch glycolate disintegrants.  


Dynamic vapor sorption (DVS) was used to determine the moisture sorption properties of sodium starch glycolates. The results were compared to similarly obtained data for potato starch, pregelatinized starch, microcrystalline cellulose (MCC), and crystalline lactose. As expected, sodium starch glycolates exhibit a large mass gain at 90% relative humidity (RH), compared to the other anhydroglucose-based excipients. However, the sorption capacities of potato starch and the modified starches between 10%-70% RH were similar. Analysis of the DVS data using the Brunauer-Emmett-Teller (BET) and Guggenheim, Anderson, and deBoer (GAB) theories to obtain the so-called monolayer (Xm), as expected, showed that there was an increasing Xm with apparent mass gain that is probably related to crystallinity, purity, and surface area and represents the number and accessibility of amorphous anhydroglucose units present. The value of x(m) was related to the degree of crystallinity or order as determined by X-ray diffraction, suggesting that x(m) can be used to further describe the amorphous nature of semi-crystalline polymers containing anhydroglucose units, in particular the chemically modified sodium starch glycolate. Additionally, it appears that the sorption capacity between 10%-70% RH is not dramatically affected by the presence or type of cross-linking and sodium carboxymethylation (in sodium starch glycolates) and gelatinization (in pregelatinized starch) and that the superdisintegrant properties of the sodium starch glycolates are a consequence of some water-structure interaction that is well beyond the available number of hydration sites, as represented by x(m). Further evaluation of the structure and sorption properties of excipients may aid the development of disintegrants for solid dosage forms. PMID:15926674

Young, Paul M; Edge, Stephen; Staniforth, John N; Steele, D Fraser; Price, Robert



Fabrication and Evaluation of Bi-layer Tablet Containing Conventional Paracetamol and Modified Release Diclofenac Sodium.  


The objectives of present investigation were to achieve immediate release of paracetamol and tailored release of diclofenac sodium from bi-layer tablets. A 2(3) full factorial design was adopted using the amount of polyethylene glycol, microcrystalline cellulose and crospovidone as independent variables for fabricating paracetamol tablets. Diclofenac sodium tablets were prepared using hydroxypropyl methylcellulose as a matrixing agent. The results of analysis of variance showed that the friability of paracetamol was distinctly influenced by the formulation variables. The in vitro drug release behaviour of diclofenac tablets was compared with a marketed formulation. The optimized formulations of paracetamol and diclofenac sodium were used for manufacturing of bi-layer tablets. The bi-layer tablets showed immediate release of paracetamol and modified release of diclofenac. PMID:20838522

Gohel, M C; Parikh, R K; Nagori, S A; Jethwa, B A



Soyabean Powder as a Novel Diluent in Tablet Formulation of Simvastatin  

PubMed Central

The present research paper introduces soyabean nuggets powder, as a novel excipient with nutraceutical value for tablets containing cholesterol lowering drug, simvastatin. Experiments were carried out to evaluate the suitability of soyabean nuggets powder as a diluent by incorporating in tablet formulation of simvastatin. The formulation was compared with the marketed product to determine its relative efficacy. Soyabean nuggets powder was found to be a promising diluent for tablets for both pharmaceutical and nutraceutical purposes. Simavastatin soya tablet showed acceptable pharmacotechnical properties and assay requirement. PMID:21218051

Swami, G.; Gupta, Khushboo; Kymonil, K. M.; Saraf, Shubhini



Preparation, characterization and tableting of cilnidipine solid dispersions.  


Solid dispersion technique has been developed many years for improving solubility of water-insoluble drugs, aiming to achieve a better oral bioavailability. However, this technique exhibits many inconveniences when used for large-scale tableting procedures. The objective of current research work was to develop cilnidipine solid dispersions (SDs) to improve the dissolution behaviors of this water-insoluble drug. Moreover, an innovative granulation method was designed to simplify the traditional tableting technology used in solid dispersion technique. Three different kinds of polymers, polyethylene glycol (PEG), polyvinylpyrrolidone (PVP) and poloxamer, were used as carriers to prepare solid dispersions. The interactions in the solid state were characterized by differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. The designed granulation method was employed to prepare solid dispersion tablets and the formulation was optimized through investigating the dissolution behaviors. The results indicated PEG solid dispersion showed the best effect both on physical characterizations and dissolution studies. Furthermore, all type of solid dispersions significantly improved the dissolution rates when compared to pure drug and its corresponding physical mixture (PM). The solid dispersion tablets prepared in simplified tableting method exhibited better operability, stability and dissolution behavior than the tablets prepared in traditional ways, which brought more opportunities to solid dispersion technique for industrial production. PMID:23625441

Hu, Liandong; Song, Weihua; Niu, Feng; Jiao, Kuiliang; Jia, Zheng



Validation of tablet-based evaluation of color fundus images  

PubMed Central

Purpose To compare diabetic retinopathy (DR) referral recommendations made by viewing fundus images using a tablet computer to recommendations made using a standard desktop display. Methods A tablet computer (iPad) and a desktop PC with a high-definition color display were compared. For each platform, two retinal specialists independently rated 1200 color fundus images from patients at risk for DR using an annotation program, Truthseeker. The specialists determined whether each image had referable DR, and also how urgently each patient should be referred for medical examination. Graders viewed and rated the randomly presented images independently and were masked to their ratings on the alternative platform. Tablet- and desktop display-based referral ratings were compared using cross-platform, intra-observer kappa as the primary outcome measure. Additionally, inter-observer kappa, sensitivity, specificity, and area under ROC (AUC) were determined. Results A high level of cross-platform, intra-observer agreement was found for the DR referral ratings between the platforms (?=0.778), and for the two graders, (?=0.812). Inter-observer agreement was similar for the two platforms (?=0.544 and ?=0.625 for tablet and desktop, respectively). The tablet-based ratings achieved a sensitivity of 0.848, a specificity of 0.987, and an AUC of 0.950 compared to desktop display-based ratings. Conclusions In this pilot study, tablet-based rating of color fundus images for subjects at risk for DR was consistent with desktop display-based rating. These results indicate that tablet computers can be reliably used for clinical evaluation of fundus images for DR. PMID:22495326

Christopher, Mark; Moga, Daniela C.; Russell, Stephen R.; Folk, James C.; Scheetz, Todd; Abramoff, Michael D.



Stability, bioavailability, and ulcerative activity of diclofenac sodium-mastic controlled release tablets.  


Controlled release tablets containing 50 mg diclofenac sodium (DS) and 40% mastic with other natural additives were prepared. Drug release was examined and stability was studied using non-isothermal and isothermal thermogravimetric analysis (TGA). The bioavailability of two controlled release tablet formulations was studied and compared to that of commercial tablets, and rabbit stomachs were also histologically examined 24 h after administration of the various tablets. Additives of pectin and sodium alginate indicated the controlled release profile of the drug. Non-isothermal TG revealed two stages of thermal decomposition for all formulations. Isothermal TG revealed that degradation of the drug in the tablet formulations follows first-order kinetics. The obtained degradation rate constants at various temperatures were plotted according to the Arrhenius equation. The degradation rate constant at 25°C was determined and used in estimation of shelf life. The obtained shelf lives of all formulations ranged from 3.38-4.92 years. In comparative studies with commercial tablets, the bioavailability of the drug from the two formulated tablets had no statistically significant difference in terms of the AUC and produced prolonged blood levels of DS with a delayed peak. The two controlled release tablet formulations resulted in no histological alterations in the stomach in terms of mucous surface cells and glands; in comparison, commercial tablets resulted in a disrupted mucous layer, necrotic ulcerations, hemorrhaging, and inflammatory cell infiltration along the base of the gastric glands. PMID:22491166

Nouh, A T; Abd El-Gawad, A H; Guda, T K



Formulation and evaluation of bilayer tablet by using melt granulation technique for treatment of diabetes mellitus  

PubMed Central

The objective of present study was to prepare and characterize Bilayer tablet formulation containing Metformin HCl in extended release matrix form and Pioglitazone HCl in immediate release form for the treatment of diabetes mellitus. Different formulations containing Metformin HCl were manufactured using 32 factorial designs. Influence of hydrophilic carrier, hydrophobic polymer on drug release was studied. Immediate release layer of Pioglitazone was optimized using different super disintegrants. All formulations were evaluated for percentage drug release. Optimization results indicated that release rate of Metformin is directly proportional to the levels of Eudragit S 100 and PEG 6000. Results confirmed that Bilayer tablet formulation containing extended release of Metformin HCl and immediate release of Pioglitazone HCl could be developed by using melt granulation technique. PMID:23066199

Patel, Dhruvita; Patel, Ankita; Solanki, Trupti



Larsen Iceshelf: Iceshelf Partial Disintegration and Iceberg Calving  

NSDL National Science Digital Library

Visitors can study this account of the calving of the Larsen ice shelf and the disintegration of the ice shelf around James Ross Island that occured in Austral Summer of 1994-95. The account is in chronolgical order and is accompanied by photographs. Follow-up examinations from 1996-2002 and links to related material are provided.


Tyrannical Greed and National Disintegration of the Sudanese Nation  

Microsoft Academic Search

The present paper is part of unpublished book divided into three interrelated manuscripts that analyze the collapse of the Sudan. The current paper conclude that the decision of the International Criminal Court to arrest President Bashir triggered a process for the disintegration of an unprecedented tyrannical regime that embezzled the Sudanese nation under the pretext of imposing Islamic Sharia Laws.

Issam A. W. Mohamed



Cultural Disintegration Perpetuated through Substance Abuse among American Indians.  

ERIC Educational Resources Information Center

Alcohol, perhaps more than any other factor, symbolizes the degree of cultural disintegration experienced by American Indians today. It has been recognized as a symptom of the numerous cultural adjustments forced upon American Indians since white contact. Indeed, alcohol among Indian groups was prohibited for a far longer period than the…

French, Laurence Armand


Mea Culpa: Formal Education and the Dis-Integrated World  

Microsoft Academic Search

Formal education has removed itself so far from any truly integrated view of the Natural World that fragmentation and certainty are prevailing ethics. Technological progress has resulted in increased specialization within academic disciplines and their concurrent separation from each other. Knowledge is extracted from a fully integrated world, but is examined and defined by the 'dis-integrated' objectives.

Brian P. Coppola; Douglas S. Daniels



Mea Culpa: Formal Education and the Dis-Integrated World  

NASA Astrophysics Data System (ADS)

Formal education has removed itself so far from any truly integrated view of the Natural World that fragmentation and certainty are prevailing ethics. Technological progress has resulted in increased specialization within academic disciplines and their concurrent separation from each other. Knowledge is extracted from a fully integrated world, but is examined and defined by the 'dis-integrated' objectives.

Coppola, Brian P.; Daniels, Douglas S.


Dabrowski's Theory of Positive Disintegration and Giftedness: Overexcitability Research Findings  

ERIC Educational Resources Information Center

During the past 20 years, a significant body of literature has emerged focusing on the application of Dabrowski's theory of positive disintegration (TPD) to the study of gifted individuals. Although much of this literature is prescriptive, some research reports spanning this time period are available. A perusal of research on TPD's applicability…

Mendaglio, Sal; Tillier, William



Development of a novel electric field-assisted modified hydrodynamic cavitation system for disintegration of waste activated sludge.  


In this current study, we present a modified hydrodynamic cavitation device that combines an electric field to substitute for the chemical addition. A modified HC system is basically an orifice plate and crisscross pipe assembly, in which the crisscross pipe imparts some turbulence, which creates collision events. This study shows that for maximizing disintegration, combining HC system, which called electric field-assisted modified orifice plate hydrodynamic cavitation (EFM-HC) in this study, with an electric field is important. Various HC systems were compared in terms of disintegration of WAS, and, among them, the EFM-HC system exhibited the best performance with the highest disintegration efficiency of 47.0±2.0% as well as the destruction of WAS morphological characteristics. The experimental results clearly show that a conventional HC system was successfully modified. In addition, electric field has a great potential for efficient disintegration of WAS for as a additional option in a combination treatment. This study suggests continued research in this field may lead to an appropriate design for commercial use. PMID:24798225

Jung, Kyung-Won; Hwang, Min-Jin; Yun, Yeo-Myeong; Cha, Min-Jung; Ahn, Kyu-Hong



A novel approach to sustained pseudoephedrine release: differentially coated mini-tablets in HPMC capsules.  


We developed and optimized a novel pseudoephedrine hydrochloride (PSE) sustained-release dosage form. The system comprises immediate-release mini-tablets (IRMT) and sustained-release mini-tablets (SRMT) contained in a hydroxypropyl methylcellulose (HPMC) capsule. The IRMT contained PSE, excipients and low-substituted hydroxypropyl cellulose (a disintegrant), and the tablets were coated with HPMC, a water-soluble polymer. IRMT prepared with varying amounts of low-substituted hydroxypropyl cellulose all dissolved completely within the first 60min, so low-substituted hydroxypropyl cellulose content does not greatly influence PSE release. The SRMT contained only PSE and excipients, and were coated with a mixture of HPMC and the water-insoluble polymer ethylcellulose. The PSE release profile for the SRMT could be controlled by varying the thickness of the coat, and the lag time could be controlled by varying the amount of ethylcellulose present in the polymer coat. PSE was released immediately from our encapsulated mini-tablet system and release was sustained over an extended period of time: the PSE in the IRMT dissolved within 60min, whereas the PSE in the SRMT was released over 8-10h. This system can be modified to yield various extended drug-release profiles, thereby harnessing the benefits of both SRMT and IRMT. PMID:18467046

Ishida, Makoto; Abe, Kenichi; Hashizume, Minoru; Kawamura, Masao



Tablet PC and Computing Curriculum Initiative Evaluation of Tablet PC Supported Pedagogy  

E-print Network

Tablet PC and Computing Curriculum Initiative 2006 Evaluation of Tablet PC Supported Pedagogy http holders react to the technology? Does the student submissions pedagogy increase engagement? Which types

Anderson, Richard


Floating tablet of trimetazidine dihydrochloride: an approach for extended release with zero-order kinetics.  


Trimetazidine dihydrochloride is an effective anti-anginal agent; however, it is freely soluble in water and suffers from a relatively short half-life. To solve this encumbrance, it is a prospective candidate for fabricating trimetazidine extended-release formulations. Trimetazidine extended-release floating tablets were prepared using different hydrophilic matrix forming polymers including HPMC 4000 cps, carbopol 971P, polycarbophil, and guar gum. The tablets were fabricated by dry coating technique. In vitro evaluation of the prepared tablets was performed by the determination of the hardness, friability, content uniformity, and weight variation. The floating lag time and floating duration were also evaluated. Release profile of the prepared tablets was performed and analyzed. Furthermore, a stability study of the floating tablets was carried out at three different temperatures over 12 weeks. Finally, in vivo bioavailability study was done on human volunteers. All tablet formulas achieved < 0.5 min of floating lag time, more than 12 h of floating duration, and extended t (1/2). The drug release in all formulas followed zero-order kinetics. T4 and T8 tablets contained the least polymer concentration and complied with the dissolution requirements for controlled-release dosage forms. These two formulas were selected for further stability studies. T8 exhibited longer expiration date and was chosen for in vivo studies. T8 floating tablets showed an improvement in the drug bioavailability compared to immediate-release tablets (Vastrel® 20 mg). PMID:20582493

Abdelbary, Ahmed; El-Gazayerly, Omaima N; El-Gendy, Nashwa A; Ali, Adel A



Light induced fluorescence for predicting API content in tablets: sampling and error.  


The use of a light induced fluorescence (LIF) instrument to estimate the total content of fluorescent active pharmaceutical ingredient in a tablet from surface sampling was demonstrated. Different LIF sampling strategies were compared to a total tablet ultraviolet (UV) absorbance test for each tablet. Testing was completed on tablets with triamterene as the active ingredient and on tablets with caffeine as the active ingredient, each with a range of concentrations. The LIF instrument accurately estimated the active ingredient within 10% of total tablet test greater than 95% of the time. The largest error amongst all of the tablets tested was 13%. The RMSEP between the techniques was in the range of 4.4-7.9%. Theory of the error associated with the surface sampling was developed and found to accurately predict the experimental error. This theory uses one empirically determined parameter: the deviation of estimations at different locations on the tablet surface. As this empirical parameter can be found rapidly, correct use of this prediction of error may reduce the effort required for calibration and validation studies of non-destructive surface measurement techniques, and thereby rapidly determine appropriate analytical techniques for estimating content uniformity in tablets. PMID:20156535

Domike, Reuben; Ngai, Samuel; Cooney, Charles L



Optimization of matrix tablets controlled drug release using Elman dynamic neural networks and decision trees.  


The main objective of the study was to develop artificial intelligence methods for optimization of drug release from matrix tablets regardless of the matrix type. Static and dynamic artificial neural networks of the same topology were developed to model dissolution profiles of different matrix tablets types (hydrophilic/lipid) using formulation composition, compression force used for tableting and tablets porosity and tensile strength as input data. Potential application of decision trees in discovering knowledge from experimental data was also investigated. Polyethylene oxide polymer and glyceryl palmitostearate were used as matrix forming materials for hydrophilic and lipid matrix tablets, respectively whereas selected model drugs were diclofenac sodium and caffeine. Matrix tablets were prepared by direct compression method and tested for in vitro dissolution profiles. Optimization of static and dynamic neural networks used for modeling of drug release was performed using Monte Carlo simulations or genetic algorithms optimizer. Decision trees were constructed following discretization of data. Calculated difference (f(1)) and similarity (f(2)) factors for predicted and experimentally obtained dissolution profiles of test matrix tablets formulations indicate that Elman dynamic neural networks as well as decision trees are capable of accurate predictions of both hydrophilic and lipid matrix tablets dissolution profiles. Elman neural networks were compared to most frequently used static network, Multi-layered perceptron, and superiority of Elman networks have been demonstrated. Developed methods allow simple, yet very precise way of drug release predictions for both hydrophilic and lipid matrix tablets having controlled drug release. PMID:22402474

Petrovi?, Jelena; Ibri?, Svetlana; Betz, Gabriele; ?uri?, Zorica



Chitosan and sodium sulfate as excipients in the preparation of prolonged release theophylline tablets.  


The major objectives of this study were to monitor the effect of cross-linking of cationic chitosan in acidic media with sulfate anion during granules preparation by wet granulation method prior to tableting using theophylline (TPH) as a model drug. The prepared granules and the compressed tablets were subjected to in vitro evaluation. The properties of the prepared matrix granules and the compressed tablets were dependent on chitosan:sodium sulfate weight ratios, chitosan content, and molecular weight of chitosan. The prepared granules of all batches showed excellent to passable flowability and were suitable for compression into tablets. Most of the granules were hard and expected to withstand handling during the subsequent compression into tablets. Granules with high friabilities were only those prepared with a high amount of sodium sulfate or low amount of chitosan. Compression of granule batches yield nondisintegrating tablets that showed a decrease in tensile strength with the increase of sodium sulfate content at high chitosan:sodium sulfate weight ratio or with decrease of chitosan content. On the other hand, friability of tablets was increased in the presence of an excessive amount of sodium sulfate and low chitosan content as observed with granules. Slow TPH release from the formulated tablets was achieved at 1:0.5 and 1:1 chitosan:sodium sulfate weight ratios where all or most of the cationic chitosan and sulfate anions were used in a cross-linking reaction during wet granulation. Ratios of 1:2 and 1:3 showed fast drug release, which support the hypothesis that excessive unreacted water-soluble sodium sulfate might increase the porosity of the nondesintegrating tablets during dissolution. Slow drug release was also obtained with high molecular weight chitosan, whereas changing the hardness of the tablets did not significantly change the release profile of the drug as long as the tablets are intact during dissolution. Furthermore, slow drug release was observed as the total amount of chitosan was increased in the formulated tablets. A comparative in vivo study between the chosen formulated tablets (1:1 chitosan:sodium sulfate ratio that contains 10% high molecular weight chitosan) and the commercial Quibron tablets indicated prolonged appearance of the drug in dogs' plasma for both formulations with no significant differences (p > 0.05) in rate and extent of drug absorption. The formulated tablets showed 103.16% bioavailability relative to that of the commercial tablets. PMID:16093204

Alsarra, Ibrahim A; El-Bagory, Ibrahim; Bayomi, Mohsen A



Disintegration of rocks based on magnetically isolated high voltage discharge  

NASA Astrophysics Data System (ADS)

Recently, a method utilizing pulsed power technology for disintegration of rocks arouses great interest of many researchers. In this paper, an improved method based on magnetic switch and the results shown that the uniform dielectrics like plastic can be broken down in water is presented, and the feasible mechanism explaining the breakdown of solid is proposed and proved experimentally. A high voltage pulse of 120 kV, rise time 0.2 ?s was used to ignite the discharging channel in solids. When the plasma channel is formed in the solid, the resistance of the channel is quiet small; even if a relatively low voltage is applied on the channel on this occasion, it will produce high current to heat the plasma channel rapidly, and eventually disintegrate the solids. The feasibility of promising industrial application in the drilling and demolition of natural and artificial solid materials by the method we presented is verified by the experiment result in the paper.

He, Mengbing; Jiang, Jinbo; Huang, Guoliang; Liu, Jun; Li, Chengzu



Formulation development and optimization of fast dissolving tablets of aceclofenac using natural superdisintegrant.  


The current research work involves preparation of fast dissolving tablets of Aceclofenac by direct compression method using different concentrations of Lepidium sativum mucilage as natural superdisintegrant. A two-factor three-level (3(2)) factorial design is being used to optimize the formulation. Nine formulation batches (D1-D9) were prepared accordingly. Two factors as independent variables (X 1-amount of ?-cyclodextrin and X 2-amount of Lepidium sativum mucilage) were taken with three levels (+1, 0, -1). The levels of two factors were selected on the basis of preliminary experiments conducted and their effect on three dependent variables (disintegration time, wetting time, and in vitro drug release) was studied along with their % prediction error. All the active blends were evaluated for postcompression parameters (angle of repose, Carr's index, Hausner ratio, etc.) and the tablets were evaluated for postcompression parameters (weight variation, hardness, and friability, wetting time, disintegration time, water absorption ratio, and in vitro drug release studies). The optimum batch was further used for SEM and stability studies. Formulation D5 was selected by the Design-Expert software which exhibited DT (15.5?sec), WT (18.94?sec), and in vitro drug release (100%) within 15 minutes. PMID:24944837

Kaur, Lovleen; Bala, Rajni; Kanojia, Neha; Nagpal, Manju; Dhingra, Gitika Arora



Interaction between Supersonic Disintegrating Liquid Jets and Their Shock Waves  

Microsoft Academic Search

We used ultrafast x radiography and developed a novel multiphase numerical simulation to reveal the origin and the unique dynamics of the liquid-jet-generated shock waves and their interactions with the jets. Liquid-jet-generated shock waves are transiently correlated to the structural evolution of the disintegrating jets. The multiphase simulation revealed that the aerodynamic interaction between the liquid jet and the shock

Kyoung-Su Im; Seong-Kyun Cheong; X. Liu; Wang Jin; M.-C. Lai; Mark W. Tate; Alper Ercan; Matthew J. Renzi; Daniel R. Schuette; Sol M. Gruner



Pharmacokinetics of naproxen after oral administration of two tablet formulations in healthy volunteers.  


The pharmacokinetics of two naproxen tablet formulations were compared after oral administration. The 250-mg naproxen tablets, tablet I from AFI, Oslo, Norway, and tablet II Naprosyn, Astra-Syntex, were taken by 12 healthy volunteers in a randomized two-period crossover study. Plasma levels of naproxen were measured by a sensitive and specific HPLC method. The data were analyzed by means of two-way analysis of variance to test for significant differences between tablet formulation and differences between the first and second trial periods. Rapid absorption, with most Cmax values from 50-60 micrograms/ml reached within 1.5-3 h, was found for both tablet formulations. No significant difference was found in the rate and extent of absorption between the two formulations: the relative bioavailability of tablet I compared to tablet II was 1.05 +/- 0.21 (mean +/- SD). The naproxen concentration 2 h after ingestion and the Cmax were higher on the second occasion, regardless of preparation, suggesting that the subjects were clinically different on the two occasions. PMID:6885201

Aarbakke, J; Gadeholt, G; Høylandskjaer, A



White matter disintegration in cluster headache  

PubMed Central

Background Previous studies in primary headache disorders showed microstructural alterations in the white matter as measured by diffusion imaging. However these investigations are not in full agreement and some of those, especially in cluster headache, restricted the analysis to only a limited number of diffusion parameters. Therefore, in the current study we examined white matter microstructure in cluster headache patients. Methods Diffusion weighted MRI images with 60 directions were acquired from thirteen patients with cluster headache and sixteen age-matched healthy controls. Tract based spatial statistics were used to compare white matter integrity in the core of the fibre bundles. Correlation of the diffusion parameters with cumulative number of headache days was examined. Results There was a significant increment of the mean, axial and perpendicular diffusivity in widespread white matter regions in the frontal, parietal, temporal and occipital lobes. Reduced fractional anisotropy was found in the corpus callosum and some frontal and parietal white matter tracts mainly in the contralateral side of the pain. Axial diffusivity showed negative correlation to the number of the headache attacks. Conclusions The in vivo analysis of microstructural alterations in cluster headache provides important features of the disease, which might offer a deeper insight into the pathomechanism of the disease. PMID:23883140



Disintegrating Asteroid P/2013 R3  

E-print Network

Splitting of the nuclei of comets into multiple components has been frequently observed but, to date, no main-belt asteroid has been observed to break-up. Using the Hubble Space Telescope, we find that main-belt asteroid P/2013 R3 consists of 10 or more distinct components, the largest up to 200 m in radius (assumed geometric albedo of 0.05) each of which produces a coma and comet-like dust tail. A diffuse debris cloud with total mass roughly 2x10^8 kg further envelopes the entire system. The velocity dispersion among the components is about V = 0.2 to 0.5 m/s, is comparable to the gravitational escape speeds of the largest members, while their extrapolated plane-of-sky motions suggest break-up between February and September 2013. The broadband optical colors are those of a C-type asteroid. We find no spectral evidence for gaseous emission, placing model-dependent upper limits to the water production rate near 1 kg/s. Breakup may be due to a rotationally induced structural failure of the precursor body.

Jewitt, David; Li, Jing; Weaver, Harold; Mutchler, Max; Larson, Stephen



Design of Controlled Release Non-erodible Polymeric Matrix Tablet Using Microwave Oven-assisted Sintering Technique.  


The objective of the present study was to evaluate the effect of sintering condition on matrix formation and subsequent drug release from polymer matrix tablet for controlled release. The present study highlights the use of a microwave oven for the sintering process in order to achieve more uniform heat distribution with reduction in time required for sintering. We could achieve effective sintering within 8 min which is very less compared to conventional hot air oven sintering. The tablets containing the drug (propranolol hydrochloride) and sintering polymer (eudragit S-100) were prepared and kept in a microwave oven at 540 watt, 720 watt and 900 watt power for different time periods for sintering. The sintered tablets were evaluated for various tablet characteristics including dissolution study. Tablets sintered at 900 watt power for 8 min gave better dissolution profile compared to others. We conclude that microwave oven sintering is better than conventional hot air oven sintering process in preparation of controlled release tablets. PMID:21897655

Patel, Dm; Patel, Bk; Patel, Ha; Patel, Cn



Preparation and Evaluation of Microencapsulated Fast Melt Tablets of Ambroxol Hydrochloride  

PubMed Central

Natural resources in general and plant materials in particular are receiving more attention due to their safety as pharmaceutical excipients. Present work assessed the potential of a natural polysaccharide, pectin to mask the bitter taste of ambroxol hydrochloride, by microencapsulation technique, and its possibility to formulate as a fast disintegrating dosage form. Taste masking is an important developmental challenge in fast dissolving drug delivery system since it dissolves or disintegrates in the patient's mouth in close proximity to the taste buds. The prepared microspheres by emulsion solvent evaporation technique possessed good sphericity, smooth surface morphology, uniform and narrow size distribution (10-90 ?m), when analyzed by scanning electron microscopy, laser diffraction and optical microscopy. Method of preparation has influenced the particle size and drug loading efficiency. Drug-polymer compatibility was confirmed by Fourier transform infrared spectroscopy and thin layer chromatography. DSC and X-ray diffraction studies revealed that the drug was dispersed inside the microspheres in the form of an insoluble matrix. The formation of microspheres was affected by glass transition temperature of the polymer, surfactant, type of plasticizers, volume of internal phase, stirrer speed etc. Fast dissolving tablets were prepared by the modification of melt granulation technique. The resulting granules were found to melt fast at body temperature, have smooth mouth feel and good physical stability. This study demonstrated that pectin could be a right choice in developing patient favored formulations for bitter drugs and can be utilized in fast disintegrating dosage forms as well. PMID:20490294

Jacob, S.; Shirwaikar, A.



21 CFR 520.1510 - Nitenpyram tablets.  

Code of Federal Regulations, 2010 CFR

...DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ...Conditions of use —(1) Dogs —(i) Amount —(A) One 11.4-mg tablet for dogs weighing less than 25 pounds...or one 57-mg tablet for dogs weighing more than 25...



21 CFR 520.312 - Carnidazole tablets.  

Code of Federal Regulations, 2013 CFR

...Conditions of use —(1) Amount. Adult pigeons: 1 tablet (10 milligrams); newly weaned pigeons: 1/2 tablet (5 milligrams). (2...trichomoniasis (canker) in ornamental and homing pigeons. (3) Limitations. Not for...



21 CFR 520.312 - Carnidazole tablets.  

...Conditions of use (1) Amount. Adult pigeons: 1 tablet (10 milligrams); newly weaned pigeons: 1/2 tablet (5 milligrams). (2...trichomoniasis (canker) in ornamental and homing pigeons. (3) Limitations. Not for...



21 CFR 520.312 - Carnidazole tablets.  

Code of Federal Regulations, 2012 CFR

...Conditions of use —(1) Amount. Adult pigeons: 1 tablet (10 milligrams); newly weaned pigeons: 1/2 tablet (5 milligrams). (2...trichomoniasis (canker) in ornamental and homing pigeons. (3) Limitations. Not for...



Multifragment disintegration of the sup 129 Xe+ sup 197 Au system at E / A =50 MeV  

SciTech Connect

Multifragment disintegrations following {sup 129}Xe+{sup 197}Au collisions at {ital E}/{ital A}=50 MeV have been studied with a multidetector system covering 88% of 4{pi} in solid angle. The average number of intermediate-mass fragments ({ital Z}=3--20) increases strongly as a function of charged-particle multiplicity and reaches values larger than six for the most violent collisions. The results are compared to calculations with both dynamical and statistical models.

Bowman, D.R.; Peaslee, G.F.; de Souza, R.T.; Carlin, N.; Gelbke, C.K.; Gong, W.G.; Kim, Y.D.; Lisa, M.A.; Lynch, W.G.; Phair, L.; Tsang, M.B.; Williams, C. (National Superconducting Cyclotron Lab., East Lansing, MI (United States) Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy); Colonna, N.; Hanold, K.; McMahan, M.A.; Wozniak, G.J.; Moretto, L.G. (Lawrence Berkeley Lab., CA (United States). Nuclear Science Div. Lawrence Berkeley Lab., CA (United States). Accelerator and Fusion Research Div.); Friedman, W.A. (University of Wisconsin, Madison, Wisconsin (United States). Department of Physics)



Comparison of extraction techniques for spray dried dispersion tablet formulations.  


Non-traditional sample preparation/extraction techniques that utilized the Caliper Life Sciences Tablet Processing Workstation II (TPW II), Microwave Assisted Extraction (MAE), and Accelerated Solvent Extraction (ASE) were evaluated for the extraction of Compound A from a 50 mgA, 15% Spray Dried Dispersion (SDD) immediate released (IR) tablet formulation. The TPW II consistently provided complete recoveries with very short preparation/extraction times (approximately 30 min). MAE also provided complete recovery of the API from the tablet formulation, but required approximately twice the extraction time, while ASE provided the lowest recovery of the three non-traditional techniques. The sample preparation/extraction efficiencies of the three non-traditional techniques were compared to that of the 5.5 h long manual method. PMID:17888606

Lee, Carlos; Gallo, Jenny; Arikpo, William; Bobin, Vincent



A randomised trial of glucose tablets to aid smoking cessation  

Microsoft Academic Search

Rationale  Oral glucose has been found to decrease tobacco craving among abstaining smokers. One study has demonstrated an effect of\\u000a glucose on short-term abstinence. There is a need to examine any long-term benefit of glucose on abstinence.\\u000a \\u000a \\u000a \\u000a Objectives  To assess whether glucose tablets improve 6-month continuous abstinence rates compared with low-calorie placebo tablets.\\u000a \\u000a \\u000a \\u000a Methods  Smokers attempting to stop (n?=?928) were randomised to receive

Robert West; Sylvia May; Andy McEwen; Hayden McRobbie; Peter Hajek; Eleni Vangeli



Safety and Colon-Cleansing Efficacy of a New Residue-Free Formulation of Sodium Phosphate Tablets  

Microsoft Academic Search

OBJECTIVE:A residue-free sodium phosphate tablet (RF-NaP) was formulated that lacks microcrystalline cellulose, which can appear as a whitish residue in the colon. A multicenter, randomized, investigator-blinded study was conducted to compare the colon-cleansing efficacy of 40 or 32 tablets of RF-NaP with the marketed 40-tablet NaP treatment regimen.METHODS:Eight hundred sixteen patients were randomized prior to colonoscopy to receive either 40

Douglas K. Rex; Howard Schwartz; Michael Goldstein; John Popp; Seymour Katz; Charles Barish; Robyn G. Karlstadt; Martin Rose; Kelli Walker; Sandra Lottes; Nancy Ettinger; Bing Zhang



Biopharmaceutical evaluation of new slow release tablets obtained by hot tableting of coated pellets with tramadol hydrochloride.  


This study was aimed at a biopharmaceutical evaluation of a new oral dosage form of tramadol hydrochloride (TH)--slow release tablets obtained by hot tableting of coated pellets, 100 mg (TP), compared to the conventional slow release tablets, Tramal Retard, 100 mg (TR). Both TP and TR formulations showed a similar release profile of TH (f2 was 71) in in vitro release studies. The in vivo study was a two-treatment, two-period, two-sequence, single-oral dose 100 mg, crossover design using rabbit model with the phases separated by a washout period of 14 days. It was shown that the amount of TH absorbed into the systemic circulation is similar for TP and TR (the 90% confidence intervals for the AUC(0-1), AUC(0-infinity) and ratios were 85-122 and 92-107%, respectively). However, after administration of slow release tablets obtained by hot tableting of coated pellets, a prolonged absorption and elimination processes and a smoother and more extended plasma profile of TH were observed. It can be assumed that the use of a new oral dosage form of TH in patients affects the extension of analgesia after single administration of the drug, with its gradual absorption into the systemic circulation. PMID:25362810

Szkutnik-Fiedler, Danuta; Sawicki, Wies?aw; Balcerkiewicz, Monika; Mazgalski, Jaros?aw; Grabowski, Tomasz; Grze?kowiak, Edmund



Scaffolding Equals Success in Teaching Tablet PCs  

ERIC Educational Resources Information Center

After many years of using the mouse and keyboard as the primary means of computer input, people are seeing a strong surge into a new generation of input technologies such as tablet PCs. As more professionals adopt tablet PCs for use in the workplace, there is a subsequent increased demand for tablet PC instruction in the classroom. Examples of…

Dickerson, Jeremy; Williams, Scott; Browning, J. B.



Mathematics Instruction and the Tablet PC  

ERIC Educational Resources Information Center

The use of tablet PCs in teaching is a relatively new phenomenon. A cross between a notebook computer and a personal digital assistant (PDA), the tablet PC has all of the features of a notebook with the additional capability that the screen can also be used for input. Tablet PCs are usually equipped with a stylus that allows the user to write on…

Fister, K. Renee; McCarthy, Maeve L.



Touch Screen Tablets and Emergent Literacy  

ERIC Educational Resources Information Center

The use of touch screen tablets by young children is increasing in the home and in early childhood settings. The simple tactile interface and finger-based operating features of tablets may facilitate preschoolers' use of tablet application software and support their educational development in domains such as literacy. This article reviews…

Neumann, Michelle M.; Neumann, David L.



Preparation, evaluation and need of spherical crystallization in case of high speed direct tabletting.  


In direct compression (DC), the significance of usual flow properties of powder from the hopper to the dies of the tablet machine cannot be overstressed. Ensuring the free flow of powder presents a number of challenges to the pharmaceutical formulator in case of high speed tabletting. This research work was conceived to obtain directly compressible agglomerates by spherical crystallization technique and were comparatively evaluated for physicochemical properties as well as tableting properties of agglomerates and unprocessed aceclofenac. Agglomerates of aceclofenac were developed via spherical crystallization method by a solvent arrangement containing dichloromethane (DCM) as a good solvent, water as a bad solvent and acetone as a bridging liquid. Hydroxypropyl cellulose (HPC) in variable quantity was implemented as hydrophilic polymer. The agglomerates were evaluated for yield, solubility, drug content, FTIR spectroscopy, porosity, particle size, micromeritic properties, differential scanning calorimetry (DSC), X-ray diffraction studies (XRD), scanning electron microscopy (SEM), and dissolution studies. The agglomerates expressed improved micromeritic and dissolution properties, in equivalence to pure drug. Formulation F3 (optimized agglomerates) exposed estimable rotundity, better drug release, and easily compression into tablets by high speed DC Technique. The tablets showed acceptable physicochemical properties and complied with the pharmacopoeial specifications. The dissolution rate of prepared tablets from agglomerates was better than the tablets of pure drug. The F3 agglomerates show splendid physicochemical and micromeritic properties. Agglomerated compression mix also showed good tableting properties as needed for high speed compression and enough stability under accelerated conditions at least for 1 month. PMID:23848355

Pandey, Suneel; Patil, Arun T



Gastro-floating tablets of cephalexin: preparation and in vitro/in vivo evaluation.  


Gastro-floating tablets of cephalexin were developed to prolong the residence time in major absorption sites. Gastro-floating tablets were prepared and optimized using hydroxypropyl methylcellulose (HPMC K100M) as matrix and sodium bicarbonate as a gas-forming agent. The properties of the tablets in terms of floating lag time, floating time and in vitro release were evaluated. Furthermore, in vivo pharmacokinetic study in fed and fasted beagle dogs was performed. The gastro-floating tablets had short floating lag time and exhibited a satisfactory sustained-release profile in vitro. Compared with conventional capsules, the gastro-floating tablets presented a sustained-release behavior with a relative bioavailability of 99.4%, while the reference sustained-release tablets gave a relative bioavailability of only 39.3%. Meanwhile, the food had significant effect on the pharmacokinetics of sustained-release tablets. It was concluded that the gastro-floating tablets had a sustained-release effect in vitro and in vivo, as well as desired pharmacokinetic properties in both fed and fasted conditions. PMID:23680730

Yin, Lifang; Qin, Chao; Chen, Kaisheng; Zhu, Chunli; Cao, Hui; Zhou, Jianping; He, Wei; Zhang, Qiang



Graft copolymers of ethyl methacrylate on waxy maize starch derivatives as novel excipients for matrix tablets: drug release and fronts movement kinetics.  


A previous paper deals with the physicochemical and technological characterization of novel graft copolymers of ethyl methacrylate (EMA) on waxy maize starch (MS) and hydroxypropylstarch (MHS). The results obtained suggested the potential application of these copolymers as excipients for compressed non-disintegrating matrix tablets. Therefore, the purpose of the present study was to investigate the mechanism governing drug release from matrix systems prepared with the new copolymers and anhydrous theophylline or diltiazem HCl as model drugs with different solubility. The influence of the carbohydrate nature, drying procedure and initial pore network on drug release kinetics was also evaluated. Drug release experiments were performed from free tablets. Radial drug release and fronts movement kinetics were also analysed, and several mathematical models were employed to ascertain the drug release mechanisms. The drug release markedly depends on the drug solubility and the carbohydrate nature but is practically not affected by the drying process and the initial matrix porosity. A faster drug release is observed for matrices containing diltiazem HCl compared with those containing anhydrous theophylline, in accordance with the higher drug solubility and the higher friability of diltiazem matrices. In fact, although diffusion is the prevailing drug release mechanism for all matrices, the erosion mechanism seems to have some contribution in several formulations containing diltiazem. A reduction in the surface exposed to the dissolution medium (radial release studies) leads to a decrease in the drug release rate, but the release mechanism is not essentially modified. The nearly constant erosion front movement confirms the behaviour of these systems as inert matrices where the drugs are released mainly by diffusion through the porous structure. PMID:22210473

Marinich, J A; Ferrero, C; Jiménez-Castellanos, M R



Cell disintegration by laser-induced transient microbubbles and its simultaneous monitoring by interferometry  

NASA Astrophysics Data System (ADS)

Selective retina treatment (SRT) is a novel short pulsed laser therapy of several retinal diseases associated with a decreased metabolism at the retinal pigment epithelium (RPE). The range of laser pulse energies is small, in which the desired selective RPE disintegration is achieved without adverse effects to the neural retina. Thus, a real-time dosimetry control is required. We investigated a noninvasive interferometric technique able to monitor microbubble formation around the intracellular melanin granula, which is the origin of the desired RPE damage. A porcine ex vivo RPE model was irradiated by single pulses (350 ns/1.7 µs) of a neodymium: yttrium lithium fluoride laser (527 nm). The specimen was simultaneously probed by a Michelson interferometer (helium neon-laser: 633 nm) and by a hydrophone. Cell viability assays (Calcein-AM) were performed after irradiation. At threshold radiant exposure for cell death (ED50=129+/-5 mJ/cm2 for 350 ns; ED50=180+/-5 mJ/cm2 for 1.7 µs), the interferometric transients changed due to microbubble formation. No major differences in the bubble dynamics were observed between both pulse durations. An algorithm to determine cell death from the interferometric transients showed less than 10% false positive or false negative results for the applied laser expositions compared to the viability assay. Interferometry is a reliable noncontact technique to monitor RPE disintegration and may serve as real-time dosimetry control during SRT.

Neumann, Jörg; Brinkmann, Ralf



Cell disintegration by laser-induced transient microbubbles and its simultaneous monitoring by interferometry.  


Selective retina treatment (SRT) is a novel short pulsed laser therapy of several retinal diseases associated with a decreased metabolism at the retinal pigment epithelium (RPE). The range of laser pulse energies is small, in which the desired selective RPE disintegration is achieved without adverse effects to the neural retina. Thus, a real-time dosimetry control is required. We investigated a noninvasive interferometric technique able to monitor microbubble formation around the intracellular melanin granula, which is the origin of the desired RPE damage. A porcine ex vivo RPE model was irradiated by single pulses (350 ns1.7 mus) of a neodymium: yttrium lithium fluoride laser (527 nm). The specimen was simultaneously probed by a Michelson interferometer (helium neon-laser: 633 nm) and by a hydrophone. Cell viability assays (Calcein-AM) were performed after irradiation. At threshold radiant exposure for cell death (ED(50)=129+/-5 mJ cm2 for 350 ns; ED50=180+/-5 mJ cm2 for 1.7 mus), the interferometric transients changed due to microbubble formation. No major differences in the bubble dynamics were observed between both pulse durations. An algorithm to determine cell death from the interferometric transients showed less than 10% false positive or false negative results for the applied laser expositions compared to the viability assay. Interferometry is a reliable noncontact technique to monitor RPE disintegration and may serve as real-time dosimetry control during SRT. PMID:16965140

Neumann, Jörg; Brinkmann, Ralf



Advantages of impact testing over hardness testing in determining physical integrity of tablets.  


An investigation of four different tablet strength tests was carried out on four different placebo formulations (differing in Avicel: Pharmatose ratios). The results analysis compared fatigue failure, work of failure, and impact failure to diametrical compression measurements (hardness). The impact results clearly show how different formulations can have the same hardness, yet their impact resistance can vary by as much as 200%. The impact test used in this work and other tests described are useful in tablet development to understand, compare, and mitigate tablet breakage during subsequent unit operations. PMID:9876556

Wilson, K E; Potter, A



Development of taste masked fast disintegrating films of levocetirizine dihydrochloride for oral use.  


Fast disintegrating films of levocetirizine dihydrochloride useful for the treatment of acute allergic rhinitis and chronic urticaria have been developed by using the taste masking ability of cyclodextrins. The fast disintegrating films were prepared by solvent casting method. The films contained water-soluble polymers such as Kollicoat IR or pullulan, aspartame and sucralose as sweeteners and pre-gelatinized starch as disintegrant. Levocetirizine dihydrochloride was incorporated into these films by in-situ complex formation with hydroxy propyl beta-cyclodextrin. The optimized films were evaluated for weight variation, film thickness, folding endurance, tackiness, tensile strength, assay, content uniformity, in vitro disintegration and dissolution, in vivo disintegration and taste masking ability by human gustatory sensation test. Results revealed that the organoleptic properties of levocetirizine dihydrochloride were improved by complexation with hydroxy propyl beta-cyclodextrin and the complex could be successfully formulated into a fast disintegrating film. PMID:19863484

Mahesh, A; Shastri, Nalini; Sadanandam, M



Real-time tablet formation monitoring with ultrasound measurements in eccentric single station tablet press.  


A real-time ultrasound measurement system for tablet compression monitoring is introduced. The measurement system was tested in actual manufacturing environment and found to be capable of measuring the ultrasound response of the tabletting process from bulk to tablet. The tablet sets were compressed and the ultrasound measurements were conducted as implemented in eccentric single station tabletting apparatus in through transmission geometry. The speed of sound and ultrasound spectrum was measured during dynamic compression for microcrystalline cellulose/paracetamol tablets. The ultrasound system introduced in this study was found to be suitable for tabletting process monitoring as the mechanical properties of compressed tablets can be estimated during compression using the ultrasound system. In addition, it was found that the ultrasound was sensitive to the mixing time of magnesium stearate and the concentration of paracetamol. Thus, ultrasound measurements made during the compression can be used to monitor the tablet formation process. PMID:22985771

Leskinen, Jari T T; Simonaho, Simo-Pekka; Hakulinen, Mikko; Ketolainen, Jarkko



In vitro and in vivo evaluation of guar gum matrix tablets for oral controlled release of water-soluble diltiazem hydrochloride.  


The objective of the study was to develop guar gum matrix tablets for oral controlled release of water-soluble diltiazem hydrochloride. Matrix tablets of diltiazem hydrochloride, using various viscosity grades of guar gum in 2 proportions, were prepared by wet granulation method and subjected to in vitro drug release studies. Diltiazem hydrochloride matrix tablets containing either 30% wt/wt low-viscosity (LM1), 40% wt/wt medium-viscosity (MM2), or 50% wt/wt high-viscosity (HM2) guar gum showed controlled release. The drug release from all guar gum matrix tablets followed first-order kinetics via Fickian-diffusion. Further, the results of in vitro drug release studies in simulated gastrointestinal and colonic fluids showed that HM2 tablets provided controlled release comparable with marketed sustained release diltiazem hydrochloride tablets (D-SR tablets). Guar gum matrix tablets HM2 showed no change in physical appearance, drug content, or in dissolution pattern after storage at 40 degrees C/relative humidity 75% for 6 months. When subjected to in vivo pharmacokinetic evaluation in healthy volunteers, the HM2 tablets provided a slow and prolonged drug release when compared with D-SR tablets. Based on the results of in vitro and in vivo studies it was concluded that that guar gum matrix tablets provided oral controlled release of water-soluble diltiazem hydrochloride. PMID:16353958

Al-Saidan, Saleh M; Krishnaiah, Yellela S R; Patro, Srinivas S; Satyanaryana, Vemulapalli



Formulation, bioavailability, and pharmacokinetics of sustained-release potassium chloride tablets.  


The release of potassium chloride incorporated into hydrogenated vegetable oil and hydroxypropyl methylcellulose matrix tablets was studied in vitro. The formulations containing 20% hydrogenated vegetable oil and hydroxypropyl methylcellulose showed a sustained-release profile comparable to that of a standard commercially available sustained-release preparation, containing 8 mEq potassium chloride embedded in a wax material. The formulated and standard sustained-release potassium chloride tablets were compared to a conventional enteric-coated potassium chloride tablet in 10 healthy subjects. Mean recoveries in 24-hr urine potassium levels from four dosage forms (after subtracting normal urine potassium excretion levels) were 76 +/- 32% from hydroxypropyl methylcellulose, 95 +/- 22% from hydrogenated vegetable oil-incorporated matrix tablets, 91 +/- 29% from commercially available sustained-release tablets, and 97 +/- 13% from enteric-coated tablets. There was no significant difference (P greater than 0.05) in the time to reach maximum excretion rates among the three sustained-release tablets. No significant adverse effect was experienced with any of the preparations. PMID:1796051

Senel, S; Capan, Y; Dalkara, T; Inanç, N; Hincal, A A



Experimental analysis of tablet properties for discrete element modeling of an active coating process.  


Coating of solid dosage forms is an important unit operation in the pharmaceutical industry. In recent years, numerical simulations of drug manufacturing processes have been gaining interest as process analytical technology tools. The discrete element method (DEM) in particular is suitable to model tablet-coating processes. For the development of accurate simulations, information on the material properties of the tablets is required. In this study, the mechanical parameters Young's modulus, coefficient of restitution (CoR), and coefficients of friction (CoF) of gastrointestinal therapeutic systems (GITS) and of active-coated GITS were measured experimentally. The dynamic angle of repose of these tablets in a drum coater was investigated to revise the CoF. The resulting values were used as input data in DEM simulations to compare simulation and experiment. A mean value of Young's modulus of 31.9 MPa was determined by the uniaxial compression test. The CoR was found to be 0.78. For both tablet-steel and tablet-tablet friction, active-coated GITS showed a higher CoF compared with GITS. According to the values of the dynamic angle of repose, the CoF was adjusted to obtain consistent tablet motion in the simulation and in the experiment. On the basis of this experimental characterization, mechanical parameters are integrated into DEM simulation programs to perform numerical analysis of coating processes. PMID:23354469

Just, Sarah; Toschkoff, Gregor; Funke, Adrian; Djuric, Dejan; Scharrer, Georg; Khinast, Johannes; Knop, Klaus; Kleinebudde, Peter



Laboratory study of gravel-bed cluster formation and disintegration  

NASA Astrophysics Data System (ADS)

knowledge of clusters is essential for the understanding of sediment transport behavior and the monitoring and protection of aquatic life. A physical study using graded river gravels is conducted in a laboratory environment. Using photogrammetry and painted gravels, a cluster identification tool (CIT) is developed based on image subtraction between subsequent frames, allowing identification of any stable areas and groups of particles on the bed. This is combined with digital particle tracking (DPT) to present a novel approach for monitoring the formation and disintegration of clusters. Clusters from graded gravels are formed successfully during the experimental stage, allowing investigation into the complex dynamic behavior of cluster formation and disintegration in a simulated natural environment. Various anchor stone arrangements are used in the experiments. However, only about one fifth of the potential anchor stones on the bed surface enable cluster formation. In general, clusters classified as "typical" and "heap" are most common. Inspection of temporal cluster coverage of the test-bed surface shows that the proportion of clusters present on the surface tends to grow with time. Maximum cluster surface coverage of between 5% and 34% is observed. In addition, particles entering and departing from clusters are monitored. Most commonly, particles enter from directly upstream of the cluster, however >20% of particles approach from a direction >20 deg from the streamwise direction. Approximately 35% of all particles directly upstream of a cluster bypass the cluster.

Heays, K. G.; Friedrich, H.; Melville, B. W.



Soot particle disintegration and detection using two laserELFFS  

SciTech Connect

A two laser technique is used to study laser-particle interactions and the disintegration of soot by high power UV light. Two separate 20 ns laser pulses irradiate combustion generated soot nanoparticles with 193 nm photons. The first laser pulse, from 0 to 14.7 J/cm{sup 2}, photofragments the soot particles and electronically excites the liberated carbon atoms. The second laser pulse, held constant at 13 J/cm{sup 2}, irradiates the remaining particle fragments and other products of the first laser pulse. The atomic carbon fluorescence at 248 nm produced by the first laser pulse increases linearly with laser fluence from 1 to 6 J/cm{sup 2}. At higher fluences, the signal from atomic carbon signal saturates. The carbon fluorescence from the second laser pulse decreases as the fluence from the first laser increases, ultimately approaching zero as first laser fluence approaches 10 J/cm{sup 2}, suggesting that the particles fully disintegrate at high laser fluences. We use an energy balance parameter, called the photon-atom ratio (PAR), to aid in understanding laser-particle interactions. These results help define the regimes where photofragmentation fluorescence methods quantitatively measure total soot concentrations.

Stipe, Christopher B.; Lucas, Donald; Koshland, Catherine P.; Sawyer, Robert F.



Graft copolymers of ethyl methacrylate on waxy maize starch derivatives as novel excipients for matrix tablets: physicochemical and technological characterisation.  


Nowadays, graft copolymers are being used as an interesting option when developing a direct compression excipient for controlled release matrix tablets. New graft copolymers of ethyl methacrylate (EMA) on waxy maize starch (MS) and hydroxypropylstarch (MHS) were synthesised by free radical polymerization and alternatively dried in a vacuum oven (OD) or freeze-dried (FD). This paper evaluates the performance of these new macromolecules and discusses the effect of the carbohydrate nature and drying process on their physicochemical and technological properties. Grafting of EMA on the carbohydrate backbone was confirmed by IR and NMR spectroscopy, and the grafting yields revealed that graft copolymers present mainly a hydrophobic character. The graft copolymerization also leads to more amorphous materials with larger particle size and lower apparent density and water content than carbohydrates (MS, MHS). All the products show a lack of flow, except MHSEMA derivatives. MSEMA copolymers underwent much plastic flow and less elastic recovery than MHSEMA copolymers. Concerning the effect of drying method, FD derivatives were characterised by higher plastic deformation and less elasticity than OD derivatives. Tablets obtained from graft copolymers showed higher crushing strength and disintegration time than tablets obtained from raw starches. This behaviour suggests that these copolymers could be used as excipients in matrix tablets obtained by direct compression and with a potential use in controlled release. PMID:19146956

Marinich, J A; Ferrero, C; Jiménez-Castellanos, M R



Using Tablets as Tools for Learner-Generated Drawings in the Context of Teaching the Kinetic Theory of Gases  

ERIC Educational Resources Information Center

Even though research suggests that the use of drawings could be an important part of learning science, learner-generated drawings have not received much attention in physics classrooms. This paper presents a method for recording students' drawings and group discussions using tablets. Compared to pen and paper, tablets offer unique benefits,…

Lehtinen, A.; Viiri, J.



Comparison of infrared attenuated total reflection and Raman spectroscopy in the quantitative analysis of diclofenac sodium in tablets  

Microsoft Academic Search

The quantification of diclofenac sodium (DS) in tablets was performed using partial least squares (PLS) models based on FTIR ATR (Fourier transform infrared attenuated total reflection) and FT-Raman spectra. Separate calibration models were built for two groups of tablets, standard and sustained release, containing different excipients. To compare the predictive ability of these models the relative standard errors of prediction

Sylwester Mazurek; Roman Szostak



A single-dose, randomized, open-label, two-period crossover bioequivalence study comparing a fixed-dose pediatric combination of lamivudine and stavudine tablet for oral suspension with individual liquid formulations in healthy adult male volunteers.  


Lamivudine (CAS 134678-17-4) is a synthetic nucleoside analogue with activity against HIV-1 and HBV. Stavudine (CAS 3056-17-5) is a synthetic thymidine nucleoside analogue, active against the human immunodeficiency virus (HIV). Lamivudine and stavudine in combination with other antiretroviral (ARV) agents are indicated for the treatment of HIV infection. As there are no suitable pediatric ARVs, adult fixed-dose ARVs are commonly used in children. This practice poses concerns about dose inaccuracy, which may lead to resistance or toxicity. A new fixed-dose combination (FDC) tablet for oral suspension, containing lamivudine 40 mg and stavudine 10 mg has been developed. An open-label, balanced, randomised, two-treatment, two-period, two-sequence, single-dose, crossover bioequivalence study was conducted following administration of a fixed-dose combination of lamivudine and stavudine tablet for oral suspension (test formulation) and innovator products (reference formulations) in healthy, adult, male human subjects under fasting condition. Multiple blood samples were collected up to 36 h post dose. Plasma concentrations of lamivudine and stavudine were assayed using validated high-performance liquid chromatography with mass spectrometry analytical method. Pharmacokinetic parameters were calculated using non-compartmental analysis and bioequivalence was assessed using a mixed effect ANOVA model. The ratio of the least-square means (FDC to individual products) and 90% confidence intervals (CIs) of AUC(0-t), AUC(0-infinity) and C(max) for lamivudine and stavudine were all within 80.00-125.00%, suggesting a similar rate and extent of ARVs exposure in the bloodstream. The FDC and individual products were equally safe and well tolerated. The current FDC of lamivudine and stavudine is expected to provide a similar efficacy/safety profile as co-administration of the individual products, a better adherence to treatment, and considerable cost savings in the treatment of HIV in children. PMID:19338141

Monif, Tausif; Reyar, Simrit; Tiwari, Hari Krishan; Tippabhotla, Sudhakar Koundinya; Khuroo, Arshad; Thudi, Nageshwar Rao; Ahmed, Sarfaraz; Raghuvanshi, Rajeev



Using NMR chemical shift imaging to monitor swelling and molecular transport in drug-loaded tablets of hydrophobically modified poly(acrylic acid): methodology and effects of polymer (in)solubility.  


A new technique has been developed using NMR chemical shift imaging (CSI) to monitor water penetration and molecular transport in initially dry polymer tablets that also contain small low-molecular weight compounds to be released from the tablets. Concentration profiles of components contained in the swelling tablets could be extracted via the intensities and chemical shift changes of peaks corresponding to protons of the components. The studied tablets contained hydrophobically modified poly(acrylic acid) (HMPAA) as the polymer component and griseofulvin and ethanol as hydrophobic and hydrophilic, respectively, low-molecular weight model compounds. The water solubility of HMPAA could be altered by titration with NaOH. In the pure acid form, HMPAA tablets only underwent a finite swelling until the maximum water content of the polymer-rich phase, as confirmed by independent phase studies, had been reached. By contrast, after partial neutralization with NaOH, the polyacid became fully miscible with water. The solubility of the polymer affected the water penetration, the polymer release, and the releases of both ethanol and griseofulvin. The detailed NMR CSI concentration profiles obtained highlighted the clear differences in the disintegration/dissolution/release behavior for the two types of tablet and provided insights into their molecular origin. The study illustrates the potential of the NMR CSI technique to give information of importance for the development of pharmaceutical tablets and, more broadly, for the general understanding of any operation that involves the immersion and ultimate disintegration of a dry polymer matrix in a solvent. PMID:24106807

Knöös, Patrik; Topgaard, Daniel; Wahlgren, Marie; Ulvenlund, Stefan; Piculell, Lennart



Use of natural gums and cellulose derivatives in production of sustained release metoprolol tablets.  


Metoprolol tartrate sustained-release tablets (100 mg) were prepared using xanthan/guar gums and also hydroxypropyl methyl cellulose (HPMC) carboxymethyl-Cellulose (CMC) polymers by direct compression method. Physical characteristics of the tablets and water uptake in addition to their dissolution profiles were compared with standard (Lopressor SR) tablets. Dissolution test was performed in the phosphate buffer solution (pH 6.8) and the samples were analyzed spectrophotometerically in 275.7 nm. Dissolution studies showed that formulations containing 100 and 80% of HPMC, 100% of guar, and 20% of xanthan followed the Higuchi model, while those containing 60 and 40% HPMC and 100 and 80% xanthan followed a zero-order model. The tablets with 40% xanthen followed a Hixon-Crowell model. In cellulose derivatives the highest MDT and dissolution efficiency until 8 hr (DE8%) belonged to tablets with 40% HPMC, increasing the amount of CMC decreased the drug release rate, and formulations containing 60 and 40% of HPMC had the USP dissolution standards. While, in the gum formulations, the highest mean dissolution time and the lowest DE(8)% belonged to tablets with 100% xanthan, increasing the xanthan decreased the release rate of metoprolol, and formulations containing 80 and 100% xanthan had the USP dissolution standards. Results showed that natural gums are suitable for production of sustained-release tablets of metoprolol. PMID:16423799

Varshosaz, Jaleh; Tavakoli, Nasser; Eram, S Ali



Investigation of critical polymer properties for polymer release and swelling of HPMC matrix tablets.  


Four different HPMC batches were characterized to investigate properties related to critical functionality for their use in hydrophilic matrix tablets. In this study, the HPMC batches were chemically characterized and correlated to the behaviour of pure HPMC tablets. Parameters such as the molecular weight, viscosity, intrinsic viscosity and radius of gyration were kept in a rather limited range, which resulted in a weak correlation to polymer release and degree of swelling. The hydrophilic/hydrophobic character of the HPMC samples was elucidated by the degree of substitution and by the clouding behaviour, where an increased hydrophilicity increased the tablet swelling. This phenomenon was interpreted in a refined model for water transport into HPMC tablets. A five times slower polymer release and a considerably larger degree of swelling were found for one batch of HPMC tablets compared to the others, although the characterized average polymer parameters were in the same range. However, the conformation plot displayed a fraction with compact aggregates. In conclusion, the existence of aggregates in aqueous solution seems to perturb the functionality of HPMC tablets and it seems important to understand and characterize these aggregates to fully predict the polymer release and swelling of HPMC tablets. PMID:19038336

Viridén, Anna; Wittgren, Bengt; Larsson, Anette



Relative bioavailability of ofloxacin tablets in comparison to oral solution.  


Single oral doses of solution and tablet preparations of 300 mg ofloxacin were given to 13 healthy male volunteers in an open, randomized crossover study. Concentrations of the unchanged drug were monitored at various times in serum and urine, over 28 hours and 48 hours, respectively. Each dose was followed by a 1-week washout period. Drug concentrations were measured both by a specific high pressure liquid chromatography (HPLC) method and a microbiological assay. A linear distribution independent regression analysis for method comparisons was calculated and good agreement between the two methods was found. Medians of maximum serum concentrations (Cmax) of ofloxacin after oral solution and tablet form were 5.0 mg/l and 3.5 mg/l, respectively. The times to maximal serum concentration (tmax) were 0.5 hr and 1.0 hr, respectively. The lower Cmax and later tmax after the tablet form were both statistically (p less than 0.05) different when compared to the corresponding values after the oral solution. However, the areas under the serum concentration-time curves (AUC0-28), as also the urinary recoveries did not differ significantly, showing that only the speed of absorption, but not the bioavailability of the tablet is changed in comparison to the oral solution form. Long-lasting, clinically relevant urine concentrations of ofloxacin were observed after both forms until the last collecting fraction (36 to 48 hours after medication). General tolerability was good; no side-effects were reported. PMID:3479296

Malerczyk, V; Verho, M; Korn, A; Rangoonwala, R



Total disintegration of Ag and Br nuclei by 4. 5[ital A] GeV/[ital c] silicon nuclei  

SciTech Connect

Complete disintegrations of Ag and Br nuclei caused by a 4.5[ital A] GeV/[ital c] [sup 28]Si projectile have been analyzed to study the characteristics of the collisions with small impact parameters. The results are systematically compared with their corresponding values obtained for the interactions with comparatively larger impact parameters at the same beam momentum per nucleon. The variations of the mean multiplicity of the relativistic charged particles with the mean number of the interacting nucleons of the projectile nuclei and the normalized pseudorapidity density have also been examined.

Ahmad, T.; Nasr, M.A.; Irfan, M. (Department of Physics, Aligarh Muslim University, Aligarh-202002 (India))



21 CFR 520.88f - Amoxicillin trihydrate tablets.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Amoxicillin trihydrate tablets. 520.88f ...ANIMAL DRUGS § 520.88f Amoxicillin trihydrate tablets. (a) Specifications... Each tablet contains amoxicillin trihydrate equivalent to 50,...



Protein analysis as a simple method for the quantitative assessment of sewage sludge disintegration  

Microsoft Academic Search

Three different parameters were tested for the description of the efficiency of sewage sludge disintegration. Two parameters were based on COD-analysis, the third parameter was the protein content. These parameters were correlated to the gas yield during anaerobic treatment after disintegration. The protein content showed the best correlation with the gas yield and, additionally, is the simplest and cheapest one

Ulrich Schmitz; Christian R. Berger; Hermann Orth



A Novel Mechanism for $J/?$ Disintegration in Relativistic Heavy Ion Collisions  

E-print Network

In this paper we discuss the possibility of $J/\\psi$ disintegration due the $Z(3)$ domain walls that are expected to form in QGP medium. These domain walls give rise to localised color electric field which disintegrates $J/\\psi$, on interaction, by changing the color composition and simultaneously exciting it to higher states of $c\\bar{c}$ system.

Abhishek Atreya; Partha Bagchi; Ajit M. Srivastava



Brief Report: Childhood Disintegrative Disorder as a Likely Manifestation of Vitamin B12 Deficiency  

ERIC Educational Resources Information Center

Childhood disintegrative disorder is a rare disorder, characterized by regression of acquired skills after a period of normal development. The case of childhood disintegrative disorder presented here was found to have vitamin B12 deficiency and hyperhomocysteinemia on extensive evaluation to find a probable cause for regression. This case…

Malhotra, Savita; Subodh, B. N.; Parakh, Preeti; Lahariya, Sanjay



Airborne imagery of a disintegrating Sargassum drift line  

NASA Astrophysics Data System (ADS)

Airborne hyperspectral and thermal infrared imagery collected over the Florida Current provide a view of the disintegration of a Sargassum drift line in 5 m s -1 winds. The drift line consists mostly of rafts 20-80 m 2 in size, though aggregations larger than 1000 m 2 also occur. Rafts tend to be elongated, curved in the upwind direction, and 0.1-0.5 °C warmer than the surrounding ocean surface. Long weed 'trails' extending upwind from the rafts are evidence of plants dropping out and being left behind more rapidly drifting rafts. The raft line may be a remnant of an earlier Sargassum frontal band, which is detectible as an upwind thermal front and areas of submerged weed. Issues are identified that require future field measurements.

Marmorino, George O.; Miller, W. D.; Smith, Geoffrey B.; Bowles, Jeffrey H.



Interaction between supersonic disintegrating liquid jets and their shock waves.  


We used ultrafast x radiography and developed a novel multiphase numerical simulation to reveal the origin and the unique dynamics of the liquid-jet-generated shock waves and their interactions with the jets. Liquid-jet-generated shock waves are transiently correlated to the structural evolution of the disintegrating jets. The multiphase simulation revealed that the aerodynamic interaction between the liquid jet and the shock waves results in an intriguing ambient gas distribution in the vicinity of the shock front, as validated by the ultrafast x-radiography measurements. The excellent agreement between the data and the simulation suggests the combined experimental and computational approach should find broader applications in predicting and understanding dynamics of highly transient multiphase flows. PMID:19257675

Im, Kyoung-Su; Cheong, Seong-Kyun; Liu, X; Wang, Jin; Lai, Ming-Chia; Tate, Mark W; Ercan, Alper; Renzi, Matthew J; Schuette, Daniel R; Gruner, Sol M



Universal scaling laws for the disintegration of electrified drops  

PubMed Central

Drops subjected to strong electric fields emit charged jets from their pointed tips. The disintegration of such jets into a spray consisting of charged droplets is common to electrospray ionization mass spectrometry, printing and coating processes, and raindrops in thunderclouds. Currently, there exist conflicting theories and measurements on the size and charge of these small electrospray droplets. We use theory and simulation to show that conductivity can be tuned to yield three scaling regimes for droplet radius and charge, a finding missed by previous studies. The amount of charge that electrospray droplets carry determines whether they are coulombically stable and charged below the Rayleigh limit of stability or are unstable and hence prone to further explosions once they are formed. Previous experiments reported droplet charge values ranging from 10% to in excess of . Simulations unequivocally show that electrospray droplets are coulombically stable at the instant they are created and that there exists a universal scaling law for droplet charge, . PMID:23487744

Collins, Robert T.; Sambath, Krishnaraj; Harris, Michael T.; Basaran, Osman A.



Interaction between Supersonic Disintegrating Liquid Jets and Their Shock Waves  

SciTech Connect

We used ultrafast x radiography and developed a novel multiphase numerical simulation to reveal the origin and the unique dynamics of the liquid-jet-generated shock waves and their interactions with the jets. Liquid-jet-generated shock waves are transiently correlated to the structural evolution of the disintegrating jets. The multiphase simulation revealed that the aerodynamic interaction between the liquid jet and the shock waves results in an intriguing ambient gas distribution in the vicinity of the shock front, as validated by the ultrafast x-radiography measurements. The excellent agreement between the data and the simulation suggests the combined experimental and computational approach should find broader applications in predicting and understanding dynamics of highly transient multiphase flows.

Im, Kyoung-Su; Cheong, Seong-Kyun; Liu, X.; Wang Jin; Lai, M.-C.; Tate, Mark W.; Ercan, Alper; Renzi, Matthew J.; Schuette, Daniel R.; Gruner, Sol M. [Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Wayne State University, Detroit, Michigan 48202 (United States); Cornell University, Ithaca, New York 14853 (United States)



Solid dispersion tablets of breviscapine with polyvinylpyrrolidone K30 for improved dissolution and bioavailability to commercial breviscapine tablets in beagle dogs.  


Breviscapine, one of cardiovascular drugs extracted from a Chinese herb Erigeron breviscapinus, has been frequently used to treat cardiovascular diseases such as hypertension, angina pectoris, coronary heart disease and stroke. However, its poor water solubility and low bioavailability in vivo severely restrict the clinical application. To overcome these drawbacks, breviscapine solid dispersion tablets consisting of breviscapine, polyvinylpyrrolidone K30 (PVP K30), microcrystalline cellulose and crospovidone were appropriately prepared. In vitro dissolution profiles showed that breviscapine released percentage of solid dispersion tablets reached 90 %, whereas it was only 40 % for commercial breviscapine tablets. Comparative pharmacokinetic study between solid dispersion tablets and commercial products was investigated on the normal beagle dogs after oral administration. Results showed that the bioavailability of breviscapine was greatly increased by 3.45-fold for solid dispersion tablets. The greatly improved dissolution rate and bioavailability might be attributed to intermolecular hydrogen bonding reactions between PVP K30 and scutellarin. These findings suggest that our solid dispersion tablets can greatly improve the bioavailability as well as the dissolution rate of breviscapine. PMID:24061692

Cong, Wenjuan; Shen, Lan; Xu, Desheng; Zhao, Lijie; Ruan, Kefeng; Feng, Yi



A study on maize proteins as a potential new tablet excipient.  


This investigation has examined the use of zein proteins from maize as the major component in oral controlled-release tablets, such formulations often being required to improve patient compliance. Tablets containing ground zein proteins, calcium hydrogen orthophosphate, polyvinyl pyrrolidone, theophylline and magnesium stearate were produced by wet granulation and compression on a single station tablet press and were compared to directly compressed tablets based on zein proteins, calcium hydrogen orthophosphate and theophylline. Non invasive techniques such as Fourier Transform infrared spectroscopy and Fourier Transform Raman spectroscopy were employed to investigate any changes in the secondary structure of zein proteins during tablet production. Random coils, alpha helices and beta sheets predominated and their relative content remained unaffected during grinding, wet granulation and compression, indicating that formulations based on zeins will be robust, i.e. insensitive to minor changes in the production conditions. Drug release from the tablets was studied using a standard pharmacopoeial dissolution test. Dissolution profiles in water, 0.1M HCl (pH=1) and phosphate buffer (pH=6.8) show that only a limited amount of theophylline was released after 4.5h, suggesting that zein proteins could act as a potential vehicle for oral controlled drug release. Analysis of the theophylline release profiles using the Peppas and Sahlin model reveals that diffusion and polymer relaxation occurred in acidic (pH=1) and buffered (pH=6.8) conditions for wet granulated tablets, whereas diffusion was predominant in directly compressed tablets. In conclusion, the present study has shown that zeins can be successfully used as a pharmaceutical excipient, and in particular as a matrix in monolithic controlled release tablets. PMID:18294824

Georget, Dominique M R; Barker, Susan A; Belton, Peter S



Mercury porosimetry of microcrystalline cellulose tablets: effect of scanning speed and moisture.  


The effect of pretreatment and scanning speed of mercury porosimetry on the porosity result of microcrystalline cellulose tablets was studied. The porosity parameters followed were total pore volume, mean and median pore size, and volume pore size distribution. Scanning speed did not affect the total pore volume of tablets compressed from microcrystalline cellulose. With increasing speed, the smallest pores of powder tablets were not properly determined, which increased the mean pore size. The median pore size of tablets compressed from powder and granules decreased and the maximum at the pore size range 500-1000 nm changed towards smaller pores with increasing scanning speed. Scanning speed appears to affect in different ways the samples with different physical structures. In tablet samples, scanning speed affects the volume of the pores at the whole pore size range determined. Thus, it is important to use about the same, reasonably low scanning speed in the measurements when comparing the samples. Swelling of microcrystalline cellulose in tablet samples is observed by mercury porosimetry measurement; a change in the pore structure is detected after storage at 88% relative humidity as increased total pore volumes and median pore sizes. Due to swelling, the maximum at the pore size range 500-2000 nm changed towards larger pores with increasing moisture. Swelling is observed similarly in tablets manufactured from powder and granules. When storing in humid conditions, water fills the smallest pores of microcrystalline cellulose powder tablets, hinders the intrusion of mercury and, thus, the mean pore size increases. Contrary to this, the volume of the smallest pores of granule tablets compressed with the highest compression pressure increased with increasing moisture. Careful pretreatment before the measurements is important. PMID:10962244

Westermarck, S



Quantitative determination of captopril and prednisolone in tablets by FT-Raman spectroscopy  

Microsoft Academic Search

A procedure for the quantitative determination of captopril and prednisolone in commercial tablets based on partial least squares (PLS) and principal component regression (PCR) treatment of FT-Raman spectroscopic data is described. In the studied medicines active pharmaceutical ingredients (APIs) constitute 4.2–16.7% of the tablet mass. Results obtained from calibration models built using unnormalised spectra were compared with the values found

Sylwester Mazurek; Roman Szostak



The content of ecstasy tablets: implications for the study of their long-term effects  

Microsoft Academic Search

Aims To examine the variation in the content of ecstasy tablets seized in the north-west of England during 2001 and to compare it to the UK average from 1991 to 2001. Measurements All tablets submitted to the Forensic Science Service in the north-west of England during 2001 were analysed by high performance liquid chromatography with diode array detection (HPLC-DAD). The

Jon C. Cole; Mike Bailey; Harry R. Sumnall; Graham F. Wagstaff; Les A. King



Studies on the compressibility of wax matrix granules of acetaminophen and their admixtures with various tableting bases.  


Matrix granules of acetaminophen have been formed by a melt granulation process whereby the acetaminophen powder was triturated with the melted wax--goat wax, glyceryl monostearate or carnuba wax. The compressibility of the matrix granules and their admixture, with diluent granules (lactose, alpha-cellulose or microcrystalline cellulose) was investigated. The granules were compressed to tablets at a constant load (30 arbitrary units on the load scale) of a manesty single punch machine. Resulting tablets were evaluated for tensile strength (T) and disintegration times (DT). Granule flow was determined by measuring their angle of repose when allowed to fall freely on a level surface. Matrix granules prepared by melt granulation with goat wax or glyceryl monostearate were too sticky and therefore did not flow at all. They were also poorly compressible (T values = 0.20MN/m2). Inclusion of the diluent remarkably improved granule flow property and compressibility. The T values of the tablets (measure of compressibility) increased from about 0.24 to 0.65 MN/m2 during increase in diluent (lactose) content from 20 to 80 %w/w. Microcrystalline cellulose and alpha-cellulose were more effective than lactose in promoting compressibility of the granules. By contrast the matrix granules formed with carnuba wax were free flowing (angle of repose, 18.60). Addition of the diluent further improved flowability slightly. The matrix granules (without a diluent) were readily compressible (T value, 1.79MN/m2). Addition of the diluent (80%w/w) reduced T values (MN/m2) slightly to 1.32 (lactose), 1.48 (alpha-cellulose) and 1.74 (microcrystalline cellulose). Tablets of the matrix granules only, disintegrated rapidly within 3 minutes. DT was further reduced to <30 s by addition of any of the diluents. The indication is that the inclusion of the diluents studied can be used to improve the compressibility of the otherwise poorly compressible matrix granules. Based on the flowability, compressibility, and disintegration data, carnuba wax proved most promising in the melt granulation of the test drug for sustained release applications. PMID:16751119

Uhumwangho, M U; Okor, R S



A study of tablet dissolution by magnetic resonance electric current density imaging  

NASA Astrophysics Data System (ADS)

The electric current density imaging technique (CDI) was used to monitor the dissolution of ion releasing tablets (made of various carboxylic acids and of sodium chloride) by following conductivity changes in an agar-agar gel surrounding the tablet. Conductivity changes in the sample were used to calculate spatial and temporal changes of ionic concentrations in the sample. The experimental data for ion migration were compared to a mathematical model based on a solution of the diffusion equation with moving boundary conditions for the tablet geometry. Diffusion constants for different acids were determined by fitting the model to the experimental data. The experiments with dissolving tablets were used to demonstrate the potential of the CDI technique for measurement of ion concentration in the vicinity of ion releasing samples.

Mikac, Urša; Demsar, Alojz; Demsar, Franci; Serša, Igor



The reality of in-line tablet coating.  


The possibility of continuous processing in pharmaceutical tablet manufacturing is hampered by the viscoelastic recovery of tablets post-compaction. Compacted tablets are typically aged before coating to allow complete viscoelastic recovery so as to avoid subsequent coating defects. There has been little attempt to overcome tablet recovery in order to enable continuous processing and improve manufacturing efficiency. However, with the introduction of improved or newly developed types of tablet-coating equipment, there is renewed interest in the coating of tablets in-line. In-line tablet coating is defined as the coating of tablets immediately after compaction. It is a one-step highly integrated system that circumvents the delay in processing time typically given to allow viscoelastic recovery of tablets. This review aims to summarize the requirements of an in-line tablet-coating system. The possibility of carrying out in-line tablet coating in the near future will also be discussed. PMID:21649557

Cahyadi, Christine; Chan, Lai Wah; Heng, Paul Wan Sia



Systemic or local treatment of erythrasma? A comparison between erythromycin tablets and Fucidin cream in general practice.  


In a Danish multi-practice study the efficacy of erythromycin tablets (Abboticin 500 mg tablets), fusidic acid cream (Fucidin cream), and placebo was compared in 86 patients (71 men and 15 women) with erythrasma. The patients were treated 'double-blind' for 14 days with either active tablets + placebo cream, placebo tablets + active cream, or placebo tablets + placebo cream. The signs of erythrasma, i.e. colour intensity, demarcation, and scaling of the affected area, as well as degree of fluorescence under Wood's light, were recorded before treatment, after one and two weeks, and at follow-up four weeks later. Cure/improvement was obtained in 77% of the cases in the erythromycin group, 87% in the fusidic acid group, and 42% in the placebo group. There was no difference between the active preparations, whereas both were significantly better than placebo, P = 0.01. PMID:2041927

Hamann, K; Thorn, P



Tablet PCs: A Physical Educator's New Clipboard  

ERIC Educational Resources Information Center

Computers in education have come a long way from the abacus of 5,000 years ago to the desktop and laptop computers of today. Computers have transformed the educational environment, and with each new iteration of smaller and more powerful machines come additional advantages for teaching practices. The Tablet PC is one. Tablet PCs are fully…

Nye, Susan B.



Putting Tablet PCs to the Test  

ERIC Educational Resources Information Center

Like many educators, the author and her colleagues (five faculty members and two IT techs) in the department of Media Communications and Technology at East Stroudsburg University in Pennsylvania were interested to find out the status of tablet PCs in education. Microsoft listed 10 manufacturers of tablet PCs following two forms: the slate and the…

Amirian, Susan



A comparison of the bioavailability of digoxin in capsule, tablet, and solution taken orally with intravenous digoxin.  


Six healthy volunteers were given five single-dose treatments of 0.40 mg digoxin either intravenously, in liquid form, in conventional tablet form (dissolution rate 76 per cent in 1-hour), or in new capsule preparations containing 0.05, 0.10, or 0.20 mg digoxin per capsule. Serum levels, area under the concentration-time curve, and daily urinary digoxin excretion were measured for six days. Higher serum digoxin levels were seen after ingestion of the capsules than after the tablets, with peak levels for the former being 2.2-2.8 times higher than after tablet digoxin. Bioavailability was assessed further by comparing the area under a six-hour concentration-time curve, and again the capsules gave a consistently higher value than the tablets. In addition, the absorption of 0.40 mg digoxin from any of the capsule preparations was much greater than 0.50 mg digoxin in commercially available tablets. The six-day cumulative urinary digoxin excretion was also greater for the capsules than for the 0.20-mg tablets. In comparison with intravenous digoxin, tablets provide 75 per cent maximum bioavailability, whereas the capsule preparations of digoxin improve the bioavailability of digoxin and the 0.20-mg digoxin capsule is absorbed better than 0.25-mg digoxin tablet. PMID:977789

Binnion, P F



Calpains mediate axonal cytoskeleton disintegration during Wallerian degeneration  

PubMed Central

In both the central nervous system (CNS) and peripheral nervous system (PNS), transected axons undergo Wallerian degeneration. Even though Augustus Waller first described this process after transection of axons in 1850, the molecular mechanisms may be shared, at least in part, by many human diseases. Early pathology includes failure of synaptic transmission, target denervation, and granular disintegration of the axonal cytoskeleton (GDC). The Ca2+-dependent proteases calpains have been implicated in GDC but causality has not been established. To test the hypothesis that calpains play a causal role in axonal and synaptic degeneration in vivo, we studied transgenic mice that express human calpastatin (hCAST), the endogenous calpain inhibitor, in optic and sciatic nerve axons. Five days after optic nerve transection and 48 hours after sciatic nerve transection, robust neurofilament proteolysis observed in wild-type controls was reduced in hCAST transgenic mice. Protection of the axonal cytoskeleton in sciatic nerves of hCAST mice was nearly complete 48 hours post-transection. In addition, hCAST expression preserved the morphological integrity of neuromuscular junctions. However, compound muscle action potential amplitudes after nerve transection were similar in wild-type and hCAST mice. These results, in total, provide direct evidence that calpains are responsible for the morphological degeneration of the axon and synapse during Wallerian degeneration. PMID:23542511

Ma, Marek; Ferguson, Toby A.; Schoch, Kathleen M.; Li, Jian; Qian, Yaping; Shofer, Frances S.; Saatman, Kathryn E.; Neumar, Robert W.



Meteoritic dust from the atmospheric disintegration of a large meteoroid.  


Much of the mass of most meteoroids entering the Earth's atmosphere is consumed in the process of ablation. Larger meteoroids (> 10 cm), which in some cases reach the ground as meteorites, typically have survival fractions near 1-25 per cent of their initial mass. The fate of the remaining ablated material is unclear, but theory suggests that much of it should recondense through coagulation as nanometre-sized particles. No direct measurements of such meteoric 'smoke' have hitherto been made. Here we report the disintegration of one of the largest meteoroids to have entered the Earth's atmosphere during the past decade, and show that the dominant contribution to the mass of the residual atmospheric aerosol was in the form of micrometre-sized particles. This result is contrary to the usual view that most of the material in large meteoroids is efficiently converted to particles of much smaller size through ablation. Assuming that our observations are of a typical event, we suggest that large meteoroids provide the dominant source of micrometre-sized meteoritic dust at the Earth's surface over long timescales. PMID:16121174

Klekociuk, Andrew R; Brown, Peter G; Pack, Dee W; ReVelle, Douglas O; Edwards, W N; Spalding, Richard E; Tagliaferri, Edward; Yoo, Bernard B; Zagari, Joseph



Management of tarsal disintegration (T.D.) in leprosy.  


Tarsal Disintegration (T.D.) is a known entity occurring exclusively in neuropathic foot of Leprosy and being influenced by several factors among which the disease itself and altered biomechanics constitute the main. In this study done on more than fifty cases at the Dr. Bandorawalla Leprosy Hospital, Kondhawa these factors have been studied in detail and it has been found that the increased and abnormal shearing forces constitute one of the major factors both in occurrence and progression of T.D. Treatment based mainly on the conservative lines is thus aimed at minimizing these forces which occur during the heel-toe pattern gait. Depending upon the severity of the case immobilization, periodic check x-rays, graded weight bearing and suitable modified footwear appliance is recommended. A Fixed Ankle Brace (FAB) serves well controlling the ankle movements by its rocker action and ultimately reducing the forces occurring during the normal heel-toe pattern. It has also been found that if the case is detected early and treated promptly the process can be controlled satisfactorily. Careful screening in high risk group is stressed and health education emphasized. PMID:2837521

Kulkarni, V N; Mehta, J M; Sane, S B; Sharangpani, R C



Systematic comparison of mechanical and thermal sludge disintegration technologies.  


This study presents a systematic comparison and evaluation of sewage sludge pre-treatment by mechanical and thermal techniques. Waste activated sludge (WAS) was pre-treated by separate full scale Thermo-Pressure-Hydrolysis (TDH) and ball milling facilities. Then the sludge was processed in pilot-scale digestion experiments. The results indicated that a significant increase in soluble organic matter could be achieved. TDH and ball milling pre-treatment could offer a feasible treatment method to efficiently disintegrate sludge and enhance biogas yield of digestion. The TDH increased biogas production by ca. 75% whereas ball milling allowed for an approximately 41% increase. The mechanisms of pre-treatment were investigated by numerical modeling based on Anaerobic Digestion Model No. 1 (ADM1) in the MatLab/SIMBA environment. TDH process induced advanced COD-solubilisation (COD(soluble)/COD(total)=43%) and specifically complete destruction of cell mass which is hardly degradable in conventional digestion. While the ball mill technique achieved a lower solubilisation rate (COD(soluble)/COD(total)=28%) and only a partial destruction of microbial decay products. From a whole-plant prospective relevant release of ammonia and formation of soluble inerts have been observed especially from thermal hydrolysis. PMID:20060704

Wett, B; Phothilangka, P; Eladawy, A



Formulation and evaluation of sustained release bioadhesive tablets of ofloxacin using 32 factorial design  

PubMed Central

Background: Oral sustained release gastroretentive dosage forms offer many advantages for drugs having absorption from upper gastrointestinal tract and improve the bioavailability of medications that are characterized by narrow absorption window. The aim of current study was to design sustained release bioadhesive gastroretentive dosage form of ofloxacin. Materials and Methods: A 32 full factorial design was employed to systematically study the drug release profile and bioadhesive strength. Carbopol 934P and HPMC K100M were selected as the independent variables. Compatibility between drug and polymer was tested by fourier transform infrared (FTIR) and X-ray diffraction (XRD) techniques. Tablets were prepared by direct compression and were evaluated for tablet characteristics, swelling study, adhesion strength, percent drug released, radiographic imaging study and stability study. The optimized formulation was then compared with marketed formulation (Oflin OD®). Results: Tablets prepared showed good tablet characteristics, optimum swelling property, and good adhesion strength with high detachment force. Most of the formulations including the optimized formulation followed Higuchi kinetics and the drug release mechanism was found to be anomalous. Radiographic image proved that tablet remains intact in its structural integrity and shape in stomach up to 24 h. The short-term accelerated stability testing was carried out for the optimized formulation, and results revealed that drug content, in-vitro dissolution and all other parameters were within acceptable limits. Conclusion: Thus, the prepared bioadhesive gastroretentive ofloxacin tablet may prove to be a potential candidate which increases the bioavailability of ofloxacin for any intragastric condition. PMID:23071937

Gangurde, Hemant H; Chordiya, Mayur A; Tamizharasi, S; Senthilkumaran, K; Sivakumar, T



Controlled-Release Carbamazepine Matrix Granules and Tablets Comprising Lipophilic and Hydrophilic Components  

PubMed Central

The objective of this study was to investigate the effect of lipophilic (Compritol® 888 ATO) and hydrophilic components (combination of HPMC and Avicel) on the release of carbamazepine from granules and corresponding tablet. Wet granulation followed by compression was employed for preparation of granules and tablets. The matrix swelling behavior was investigated. The dissolution profiles of each formulation were compared to those of Tegretol® CR tablets and the mean dissolution time (MDT), dissolution efficiency (DE%), and similarity factor (f2 factor) were calculated. It was found that increase in the concentration of HPMC results in reduction in the release rate from granules and achievement of zero-order is difficult from the granules. The amount of HPMC plays a dominant role for the drug release. The release mechanism of CBZ from matrix tablet formulations follows non-Fickian diffusion shifting to Case II by the increase of HPMC content, indicating significant contribution of erosion. Increasing in drug loading resulted in acceleration of the drug release and in anomalous controlled-release mechanism due to delayed hydration of the tablets. These results suggest that wet granulation followed by compression could be a suitable method to formulate sustained release CBZ tablets. PMID:19555310

Barakat, Nahla S.; Elbagory, Ibrahim M.; Almurshedi, Alanood S.



Self nano-emulsifying simvastatin based tablets: design and in vitro/in vivo evaluation.  


The aim of this work is to improve the oral bioavailability of poorly water soluble drug, simvastatin (SV) through combining the advantages of self-nanoemulsifying systems (SNEs) and tablets. Ternary phase diagram was constructed using Labrafil, Tween 80 and Transcutol, in order to evaluate self-nanoemulsification domain. The particle size distribution and zeta potential of the prepared systems were evaluated using Malvern Zetasizer. Liquisolid powders were prepared using Aeroperl(®) as a coating material and Avicel(®) or Starch 1500 as carrier materials, the powder flow properties were then evaluated. Compressed SV SNE based tablets were evaluated regarding their physical characteristics, in-vitro release properties as well as in-vivo pharmacokinetic evaluation in six healthy human volunteers using a validated LC/MS/MS method. The in-vitro release results revealed that the developed SNE based tablets improved the release of SV significantly, compared to commercially available SV tablets (Zocor(®)). The optimal SV SNE tablet formulation was S3St10 (10% Labrafil, 60% Tween 80, and 30% Transcutol). The in-vivo evaluation of S3St10 revealed that rapid and enhanced absorption of SV could be obtained from the SNE based tablet, with a 1.5 fold increase in bioavailability than that obtained after administration of Zocor(®). Hence such an approach could be promising in improving the bioavailability of SV. PMID:22468935

Abdelbary, Ghada; Amin, Maha; Salah, Salwa



Effect of controlled-release metoprolol on blood pressure and exercise heart rate in hypertension: A comparison with conventional tablets  

Microsoft Academic Search

Summary In a double-blind study with parallel groups a new controlled-release (CR) formulation of metoprolol1, 100 mg once daily, was compared with conventional metoprolol tablets, 100 mg once daily, in 27 patients with primary hypertension.

L. Rydén; B. E. Kristensson; G. Westergren



Low volume bowel preparation for colonoscopy: randomized, endoscopist-blinded trial of liquid sodium phosphate versus tablet sodium phosphate  

Microsoft Academic Search

ObjectiveThe aim of this study was to compare the colon-cleansing effectiveness, ease of consumption, and side effect profiles of two commercially available preparations of sodium phosphate: liquid Fleet Phospho-soda and Visicol tablets.

David H Balaban; Byrd S Leavell; Michael J Oblinger; William O Thompson; Nancy D Bolton; Daniel J Pambianco



78 FR 74154 - Draft Guidance for Industry on Size, Shape, and Other Physical Attributes of Generic Tablets and...  

Federal Register 2010, 2011, 2012, 2013

...Physical Attributes of Generic Tablets and Capsules...Availability AGENCY: Food and Drug Administration, HHS...these characteristics of generic drugs are too varied compared...characteristics of the originator drug when developing a generic version. This...



Single dose bioavailability of two different digoxin tablets.  


In a single dose bioequivalence study in 10 healthy young adults the absorption profiles and bioavailability of two digoxin containing tablets (A = digoxin-Pharbita 0.25 mg and reference drug B) were compared and related to the in vitro dissolution rate of both tablets. Two tablets of each product (= 0.50 mg of digoxin) were taken at random on an empty stomach; two weeks elapsed between the two treatments. Frequent blood sampling was performed up to 24 h after intake of the dose. Digoxin plasma concentrations were measured by means of radioimmunoassay. No significant differences (p greater than 0.05) were found in the mean values of the peak plasma concentration (cmax), time to peak (tmax) and area under the plasma concentration versus time curve for the period of 0-10 h after drug intake (AUC0-10), although in most subjects the absorption process after intake of product A was slightly faster, with slightly higher peak. This might be related to a slightly faster release of digoxin from the product A dosage form, as was seen from the dissolution test data. The relative bioavailability of product A as compared to product B, accounted for 97.7 +/- 28.7% (mean +/- S.D.). These results indicate, that both products can be considered as being bioequivalent. PMID:3566859

Jonkman, J H; Gusdorf, C F; van der Boon, W J; Grasmeijer, G; Jedema, J N



Identity, Rationality, and Emotion in the Processes of State Disintegration and Reconstruction  

E-print Network

I wish to address both a substantive and a methodological issue in this chapter. Substantively, I will discuss the process of state disintegration and reconstruction. Here, I will draw on the experience of Eastern Europe ...

Petersen, Roger D.


75 FR 39025 - Determination That ACTONEL (Risendronate Sodium) Tablets, 75 Milligrams, and ACTONEL WITH CALCIUM...  

Federal Register 2010, 2011, 2012, 2013

...CALCIUM (Risendronate Sodium and Calcium Carbonate (Copackaged)) Tablets, 35...CALCIUM (risendronate sodium and calcium carbonate (copackaged)) Tablets, 35...CALCIUM (risendronate sodium and calcium carbonate (copackaged)) Tablets,...



Laser irradiation induced disintegration of a bubble in a glass melt  

Microsoft Academic Search

We report on removal of micrometer-sized bubbles from molten glass by a 1064 nm wavelength cw-laser radiation focused using\\u000a an objective lens of numerical aperture 0.55. The heating of a bubble and surrounding glass by tightly focused laser beam\\u000a had reduced surface tension and caused disintegration of the bubble. Disintegration occurred at typically 185050 C. Emission\\u000a of a heated gas inside the

S. Juodkazis; N. Murazawa; H. Wakatsuki; H. Misawa



Functional disintegration in paranoid schizophrenia using resting-state fMRI  

Microsoft Academic Search

Functional disintegration has been observed in schizophrenia during task performance. We sought to investigate functional disintegration during rest because an intrinsic functional brain organization, including both “task-negative” (i.e., “default mode”) and “task-positive” networks, has been suggested to play an important role in integrating ongoing information processing. Additionally, the brain regions that are involved in the intrinsic organization are believed to

Yuan Zhou; Meng Liang; Lixia Tian; Kun Wang; Yihui Hao; Haihong Liu; Zhening Liu; Tianzi Jiang



Properties of lipophilic matrix tablets containing phenylpropanolamine hydrochloride prepared by hot-melt extrusion.  


The objective of the present study was to investigate the influence of formulation factors on the physical properties of hot-melt extruded granules and compressed tablets containing wax as a thermal binder/retarding agent, and to compare the properties of granules and tablets with those prepared by a high-shear melt granulation (MG) method. Powder blends containing phenylpropanolamine hydrochloride, Precirol and various excipients were extruded in a single-screw extruder at open-end discharge conditions. The extrudates were then passed through a 14-mesh screen to form granules. The extrusion conditions and the optimum amount of wax to function as the thermal binder were dependent on the properties of the filler excipients. At the same wax level, drug release from tablets decreased in the order of using microcrystalline cellulose (MCC), lactose and Emcompress as the filler excipient. The observed differences in the dissolution properties of the tablets were due to the differences in the solubility, swellability and density of the filler excipients. Replacing Precirol with Sterotex K, a higher melting point wax, resulted in slightly increased dissolution rates, when the extrusion was performed at the same temperature conditions. Hot-melt extruded granules were observed to be less spherical than high-shear melt granules and showed lower values of bulk/tap densities. However, tablets containing MCC or lactose granules prepared by hot-melt extrusion (HME) exhibited higher hardness values. Slower drug release rates were found for tablets containing MCC by HME compared with MG. Analysis of the hot-melt extruded granules showed better drug content uniformity among granules of different size ranges compared with high-shear melt granules, resulting in a more reproducible drug release from the corresponding tablets. PMID:11522484

Liu, J; Zhang, F; McGinity, J W



Optimization and in vivo pharmacokinetic study of a novel controlled release venlafaxine hydrochloride three-layer tablet.  


Several matrix tablet formulations (hydrophilic-based, wax-based, and three-layer tablets) were designed for controlling the release of the highly water soluble drug, venlafaxine hydrochloride (VenHCl) for once-daily administration. The three-layer tablets consist of non-swellable, compritol-based middle layers containing the drug to which hydrophilic top and bottom barrier layers were applied. A 2(3) full-factorial design was employed for optimization and to explore the effect of different variables on the release rate of the drug from the three-layer tablets. The optimized levels of each independent variable were based on the criterion of desirability. The calculated values of f(1) and f(2) were 4.131 and 79.356, respectively; indicating that the release profile of the optimized PEO layered tablet formulation is comparable to that of the target release model. The pharmacokinetic parameters of VenHCl from the optimized three-layer tablet was compared to the marketed extended release capsule as a reference in healthy human subjects using a randomized crossover design. In this study, the 90% confidence interval for AUC(0-24) and AUC(0-?) are within (0.8-1.25), which satisfied the bioequivalence criteria. It could be concluded that a promising once-daily extended-release three-layer tablet of the highly water soluble drug, VenHCl, was successfully designed. PMID:20532709

Aboelwafa, Ahmed A; Basalious, Emad B



Modeling drug release from PVAc/PVP matrix tablets.  


Kollidon SR-based matrix tablets containing various amounts of diprophylline were prepared and thoroughly characterized in vitro. This includes drug release measurements in 0.1M HCl and phosphate buffer pH 7.4, monitoring of changes in the tablet's height and diameter, morphology as well as dry mass upon exposure to the release media. Based on these experimental results, a mechanistic realistic mathematical theory is proposed, taking into account the given initial and boundary conditions as well as radial and axial mass transport in cylinders. Importantly, good agreement between theory and experiment was obtained in all cases, indicating that drug diffusion with constant diffusivity is the dominant mass transport mechanism in these systems. Furthermore, the proposed theory was used to quantitatively predict the effects of the initial tablet height and diameter on the resulting drug release patterns. These theoretical predictions were compared with independently measured drug release kinetics. Good agreement was observed in all cases, proving the validity of the mathematical theory and illustrating the latter's practical benefit: The model can help to significantly facilitate the recipe optimization of this type of advanced drug delivery systems in order to achieve a desired release profile. PMID:19737588

Siepmann, F; Eckart, K; Maschke, A; Kolter, K; Siepmann, J



FT-Raman quantitative determination of ambroxol in tablets  

NASA Astrophysics Data System (ADS)

A procedure for quantitative determination of ambroxol in commercial tablets by Partial Least Squares (PLS) treatment of FT-Raman spectroscopic data is proposed. In a number of published reports, the quantification of pharmaceuticals, usually containing 30-90% of the analysed ingredient, with the application of the Raman technique is described. In the product under consideration, the active component constitutes less than 15% of the tablet mass. A calibration model was built using unnormalized spectra and the results obtained were compared with values found from a second approach in which an internal standard was added to each sample. To appraise the quality of the PLS models, the relative standard error of prediction (RSEP) was calculated. For ambroxol, it amounts to 2.3-3.0% for a testing sample set quantification. The mean content of ambroxol in tablets determined from the model based on unnormalised spectra equals 29.6±0.4 mg. It was found to be 29.6±0.6 mg and 30.8±0.3 mg from models built using spectra normalised by the intensity at maximum and integral intensity of the internal standard band, respectively. These values correlate well with the declared value of 30 mg of ambroxol in the studied medicine.

Szostak, Roman; Mazurek, Sylwester



Difference in the lubrication efficiency of bovine and vegetable-derived magnesium stearate during tabletting.  


The purpose of this work was to evaluate and compare the functionality of bovine fatty acids-derived (MgSt-B) and vegetable fatty acids-derived (MgSt-V) magnesium stearate powders when used for the lubrication of granules prepared by high-shear (HSG) and fluid bed (FBG) wet granulation methods. The work included evaluation of tablet compression and ejection forces during tabletting and dissolution testing of the compressed tablets. Granules prepared by both granulation methods required significantly lower ejection force (p < 0.01) when lubricated with the MgSt-V powder as compared to those lubricated with the MgSt-B powder. Granules prepared by the HSG method and lubricated with the MgSt-V powder also required significantly lower compression force (p < 0.01) to produce tablets of similar weight and hardness as compared to those lubricated with the MgSt-B powder. The dissolution profiles were not affected by these differences and were the same for tablets prepared by same granulation method and lubricated with either magnesium stearate powder. The results indicate significant differences (p < 0.01) between lubrication efficiency of the MgSt-B and the MgSt-V powders and emphasize the importance of functionality testing of the MgSt powders to understand the impact of these differences. PMID:19390976

Gupta, Abhay; Hamad, Mazen L; Tawakkul, Mobin; Sayeed, Vilayat A; Khan, Mansoor A



In vitro release of valerenic and hydroxyvalerenic acids from valerian tablets.  


Although most commercial valerian formulations are coated tablets not any comparison study of their drug release profiles has been published so far. The main objective of this work is to establish a drug release test suitable for studying and comparing different valerian tablets. Thus, hydroxyvalerenic and valerenic acid concentrations were assayed by HPLC using a C18 Kromasil (200 x 4.6 mm, 5 microm) column and a mobile phase containing methanol and an orthophosphoric acid solution 0.5% v/v in water at a ratio of 75:25 at a constant flow rate of 1 ml/min. Saturation solubilities for hydroxyvalerenic and valerenic acid at pH 6.8 were 26 +/- 5.1 and 1 +/- 0.6 microg/ml, respectively. Usually for drugs with such low solubility values, their oral absorption and hence bioavailability are limited by their dissolution characteristics. A dissolution test was conducted according to the general method 2 (paddles) of USP 24 using 500 ml buffer medium (pH 6.8) at 50 rpm. Five different formulations were studied and compared: one uncoated tablet formulation and four marketed coated tablets. The uncoated tablet formulation had the fastest release profile, whereas the coated tablets manifested very different release patterns, depending on the type of formulation. Because of these differences in drug release pattern not every tablet formulation may be appropriate for the same clinical indications. Clinical data are required to confirm the correlation between drug release pattern and the therapeutically value of each formulation. PMID:14531459

Torrado, J J



Tablets for Timely Design Documentation  

NSDL National Science Digital Library

One of the biggest challenges we have experienced in supervising digital systems senior design projects is the quality and completeness of the individual lab notebooks. Of the five outcomes we continuously track for this capstone course, the lab notebooks have consistently received the lowest quantitative scores. A significant improvement was achieved three years ago when we transitioned from carbon paper and pen notebooks to on-line (HTML) notebooks. Many teams took advantage of (and put to good use) the ability to post digital pictures of prototyping setups, provide hyperlinks to all their device datasheets, post their latest schematics and software listings for evaluation, and post video clips of their project in action (as verification of their project success criteria). The primary drawback has been the need for students to be in front of a networked computer to make lab notebook entries; consequently, the notebook updates still tended to be done in spurts (typically after the fact) rather than in real time. Project work (and inspiration), in fact, does not always occur in a lab setting, where networked computers are readily available, nor does it occur when all team members are working in the same physical location. Our hypothesis is that equipping each project team with wireless Tablet PCs should not only significantly improve the spontaneity (and regularity) with which the on-line lab notebooks are updated, but also facilitate collaboration among team members working on the design project at different locations. An HP Technology for Teaching Grant has provided a critical mass of Tablet PCs to test this hypothesis. A description of how the equipment provided is being utilized, along with a discussion of the preliminary results obtained, is presented in this paper.

Brown, Cordelia; Johnson, Mark; Meyer, David



Pharmaceutical tablet compaction : product and process design  

E-print Network

This thesis explores how tablet performance is affected by microstructure, and how microstructure can be controlled by selection of excipients and compaction parameters. A systematic strategy for formulation and process ...

Pore, Mridula



Onsite Wastewater Treatment Systems: Tablet Chlorination  

E-print Network

Wastewater that is sprayed onto lawns must first be disinfected to prevent odors and remove disease-causing organisms. This publication explains how tablet chlorinators disinfect wastewater and gives tips on how to maintain them....

Lesikar, Bruce J.



21 CFR 520.1870 - Praziquantel tablets.  

...tablets to weak or debilitated animals and for assistance in the diagnosis, treatment, and control of parasitism. (B) If weak or debilitated animals, and for assistance in the diagnosis, treatment, and control of parasitism. [46 FR...



Chitosan-kaolin coprecipitate as disintegrant in microcrystalline cellulose-based pellets elaborated by extrusion-spheronization.  


The usefulness of a coprecipitate of chitosan and kaolin as disintegrant in the pellets of microcrystalline cellulose (MCC) and hydrochlorothiazide (HCT) (as a model of poorly water-soluble drug) produced by extrusion-spheronization was evaluated in this study. The effectiveness of chitosan-kaolin coprecipitate to increase the dissolution rate was compared with that of kaolin and chitosan. A possible synergy effect was also evaluated between the coprecipitate, kaolin or chitosan and sorbitol, added to the pellets as a very water-soluble diluent. The chitosan-kaolin coprecipitate, the kaolin or the chitosan allowed pellets to be obtained of adequate size, roundness, mechanical strength and flow properties. Furthermore, the incorporation of chitosan-kaolin coprecipitate or chitosan significantly increased the dissolution rate of HCT independently of the sorbitol content. The effects on the dissolution of HCT derived from the incorporation of coprecipitate to the pellets can be attributed to its content of chitosan. However, the addition of kaolin into the pellets did not significantly affect the HCT dissolution process. The pellets incorporating coprecipitated chitosan-kaolin or chitosan and the maximum proportion of sorbitol (50%) led to the highest HCT dissolution rate and experienced a rapid and complete disintegration in the dissolution medium. PMID:22309024

Goyanes, Alvaro; Souto, Consuelo; Martínez-Pacheco, Ramón



Early clinical development of artemether-lumefantrine dispersible tablet: palatability of three flavours and bioavailability in healthy subjects  

PubMed Central

Background Efforts to ease administration and enhance acceptability of the oral anti-malarial artemether-lumefantrine (A-L) crushed tablet to infants and children triggered the development of a novel dispersible tablet of A-L. During early development of this new formulation, two studies were performed in healthy subjects, one to evaluate the palatability of three flavours of A-L, and a second one to compare the bioavailability of active principles between the dispersible tablet and the tablet (administered crushed and intact). Methods Study 1 was performed in 48 healthy schoolchildren in Tanzania. Within 1 day, all subjects tasted a strawberry-, orange- and cherry-flavoured oral A-L suspension for 10 seconds (without swallowing) in a randomized, single-blind, crossover fashion. The palatability of each formulation was rated using a visual analogue scale (VAS). Study 2 was an open, randomized crossover trial in 48 healthy adults given single doses of A-L (80 mg artemether + 480 mg lumefantrine) with food. The objectives were to compare the bioavailability of artemether, dihydroartemisinin (DHA) and lumefantrine between the dispersible tablet and the tablet administered crushed (primary objective) and intact (secondary objective). Results Study 1 showed no statistically significant difference in VAS scores between the three flavours but cherry had the highest score in several ratings (particularly for overall liking). Study 2 demonstrated that the dispersible and crushed tablets delivered bioequivalent artemether, DHA and lumefantrine systemic exposure (area under the curve [AUC]); mean ± SD AUC0-tlast were 208 ± 113 vs 195 ± 93 for artemether, 206 ± 81 vs 199 ± 84 for DHA and 262 ± 107 vs 291 ± 106 h.?g/ml for lumefantrine. Bioequivalence was also shown for peak plasma concentrations (Cmax) of DHA and lumefantrine. Compared with the intact tablet, the dispersible tablet resulted in bioequivalent lumefantrine exposure, but AUC and Cmax values of artemether and DHA were 20-35% lower. Conclusions Considering that cherry was the preferred flavour, and that the novel A-L dispersible tablet demonstrated similar pharmacokinetic performances to the tablet administered crushed, a cherry-flavoured A-L dispersible tablet formulation was selected for further development and testing in a large efficacy and safety study in African children with malaria. PMID:20815879



Bioavailability of ibuprofen from matrix mini-tablets based on a mixture of starch and microcrystalline wax.  


The bioavailability of ibuprofen from matrix mini-tablets based on microcrystalline wax and a starch derivative was tested. An oral dose of 300 mg of ibuprofen was administered to healthy volunteers (n=8) in a randomized cross-over study design either as a commercial matrix formulation (Ibu-Slow 600) or as mini-tablets (filled into hard gelatin capsules). The mini-tablets consisted of 60% ibuprofen, 15% Paracera M (wax), 22.5% DDWM (starch) and 2.5% triacetin (lubricant). t50% of the in vitro release was 4.5 and 5 h for the mini-tablet and Ibu-slow formulations, respectively. Both formulations behaved in vivo as sustained-release formulation; their HVDt50%Cmax value was determined at 5.6 and 5.1 h for the mini-tablet and Ibu-slow formulations, respectively. A significantly higher value of Cmax was seen for the mini-tablet formulation, resulting in a relative bioavailability of 116 +/- 22.6% compared to the Ibu-slow matrix. These data demonstrate that the experimental mini-tablets can be used to formulate sustained-release dosage forms. PMID:11203270

De Brabander, C; Vervaet, C; Görtz, J P; Remon, J P; Berlo, J A



Evaluation of contents-based image retrieval methods for a database of logos on drug tablets  

NASA Astrophysics Data System (ADS)

In this research an evaluation has been made of the different ways of contents based image retrieval of logos of drug tablets. On a database of 432 illicitly produced tablets (mostly containing MDMA), we have compared different retrieval methods. Two of these methods were available from commercial packages, QBIC and Imatch, where the implementation of the contents based image retrieval methods are not exactly known. We compared the results for this database with the MPEG-7 shape comparison methods, which are the contour-shape, bounding box and region-based shape methods. In addition, we have tested the log polar method that is available from our own research.

Geradts, Zeno J.; Hardy, Huub; Poortman, Anneke; Bijhold, Jurrien



Caspase-3 is required in the apoptotic disintegration of the nuclear matrix  

SciTech Connect

Apoptotic breakdown of cellular structures is largely mediated by caspases. One target of degradation is a proteinaceous framework of the nucleus termed the nuclear matrix. We compared the apoptotic changes of the nuclear matrix in staurosporine-treated caspase-3-deficient MCF-7 cells transfected with intact CASP-3 gene (MCF-7c3) or an empty vector (MCF-7v) as a control. Nuclear Mitotic Apparatus protein (NuMA), lamin A/C and lamin B were used as markers for internal nuclear matrix and peripheral nuclear lamina, respectively. In both cell lines, staurosporine induced rapid cytoplasmic shrinkage and partial chromatin condensation. MCF-7c3 cells formed apoptotic bodies, whereas MCF-7v cells did not. NuMA and lamins were actively cleaved in MCF-7c3 cells following caspase-3 activation, but only minimal or no cleavage was detected in MCF-7v cells. Interestingly, lamin B but not lamin A/C was relocated into cytoplasmic granules in apoptotic MCF-7v cells. Pancaspase inhibitor, z-VAD-fmk, prevented the apoptotic changes, while caspase-3 inhibitor, z-DEVD-fmk, induced lamin B granules in both cell lines. These results show that caspase-3 is involved in the cleavage of NuMA and lamins either directly or by activating other proteases. This may be essential for disintegration of the nuclear structure during apoptosis.

Kivinen, Katri [Department of Pathology, University of Turku, MediCity Research Laboratory, Tykistoekatu 6 A, 4th floor, FIN-20520 Turku (Finland); Turku Graduate School of Biomedical Sciences, Turku (Finland); Kallajoki, Markku [Department of Pathology, University of Turku, MediCity Research Laboratory, Tykistoekatu 6 A, 4th floor, FIN-20520 Turku (Finland); Taimen, Pekka [Department of Pathology, University of Turku, MediCity Research Laboratory, Tykistoekatu 6 A, 4th floor, FIN-20520 Turku (Finland)]. E-mail:



Rayleigh-Taylor Instability in Disintegration of Liquid Globule due to Constant Acceleration  

NASA Astrophysics Data System (ADS)

Fragmentation of droplets is of fundamental importance in several applications, from volcanic eruption to combustion engines. In the current study, the fragmentation of an initially spherical droplet accelerated by a constant body force is examined in 3D. A finite volume-volume of fluid (FV-VOF) numerical technique is employed for direct numerical simulation (DNS) of the two-phase system. The numerical code uses a combination of octree spatial discretization and a multilevel Poisson solver. It is shown that the fragmentation has four main steps: 1-Deformation of the initially spherical droplet and bag formation. 2-Bursting of the bag generating upper and lower tori. 3-Deformation and breakup of the tori. 4-Disintegration of remaining ligaments and drops. The role of Rayleigh-Taylor instability (RTI) at each step is studied in detail. It is showed RTI is the prevailing mechanism in bursting of the bag, flattened core and tori. Stability analyses are also provided based on the linearized Navier-Stokes equations, and the most amplified wave numbers were compared with the observations in DNS. Reasonable agreement is observed between the numerical and analytical solutions.

Jalaal, Maziyar; Mehravaran, Kian



Development of novel fast-dissolving tacrolimus solid dispersion-loaded prolonged release tablet.  


The goal of this research was to develop a novel prolonged release tablet bioequivalent to the commercial sustained release capsule. A number of tacrolimus-loaded fast-dissolving solid dispersions containing various amounts of DOSS were prepared using the spray drying technique. Their solubility, dissolution and pharmacokinetics in rats were studied. DOSS increased drug solubility and dissolution in the solid dispersions. Compared with the drug powder, the solubility, dissolution and bioavailability of tacrolimus with the fast-dissolving solid dispersion containing tacrolimus/HP-?-CD/DOSS in the weight ratio of 5:40:4 were boosted by approximately 700-, 30- and 2-fold, respectively. Several tablet formulations were accomplished with this solid dispersion in combination with various ratios of HPMC/ethylcellulose. The release behaviour and pharmacokinetic studies in beagle dogs were assessed compared with the commercial prolonged release capsule. A decrease in HPMC/ethylcellulose ratios reduced the dissolution of tacrolimus from the tablets. Particularly, the tacrolimus-loaded prolonged release tablet consisting of fast-dissolving tacrolimus solid dispersion, HPMC, ethylcellulose and talc at the weight ratio of 20:66:112:2 exhibited a dissolution profile similar to that produced by the commercial prolonged release capsule. Furthermore, there were no significant differences in the AUC, Cmax, Tmax and MRT values between them in beagle dogs. Consequently, this tacrolimus-loaded prolonged release tablet might be bioequivalent to the tacrolimus-loaded commercial capsule. PMID:24388864

Cho, Jung Hyun; Kim, Yong-Il; Kim, Dong-Wuk; Yousaf, Abid Mehmood; Kim, Jong Oh; Woo, Jong Soo; Yong, Chul Soon; Choi, Han-Gon



Prospective Pilot Study of a Tablet Computer in an Emergency Department  

PubMed Central

Background The recent availability of low-cost tablet computers can facilitate bedside information retrieval by clinicians. Objective To evaluate the effect of physician tablet use in the emergency department. Design Prospective cohort study comparing physician workstation usage with and without a tablet. Setting 55,000 visits/year Level 1 Emergency Department at a tertiary academic teaching hospital. Participants 13 emergency physicians (7 Attendings, 4 EM3s, and 2 EM1s) worked a total of 168 scheduled shifts (130 without and 38 with tablets) during the study period. Intervention Physician use of a tablet computer while delivering direct patient care in the Emergency Department. Main Outcome Measures The primary outcome measure was the time spent using the Emergency Department Information System (EDIS) at a computer workstation per shift. The secondary outcome measure was the number of EDIS logins at a computer workstation per shift. Results Clinician use of a tablet was associated with a 38-minute (17-59) decrease in time spent per shift using the EDIS at a computer workstation (p<0.001) after adjusting for clinical role, location, and shift length. The number of logins was also associated with a 5-login (2.2-7.9) decrease per shift (p<0.001) after adjusting for other covariates. Conclusion Clinical use of a tablet computer was associated with a reduction in the number of times physicians logged into a computer workstation and a reduction in the amount of time they spent there using the EDIS. The presumed benefit is that decreasing time at a computer workstation increases physician availability at the bedside. However, this association will require further investigation. PMID:22226927

Horng, Steven; Goss, Foster R.; Chen, Richard S.; Nathanson, Larry A.



The Laws of Conservation of Momentum, Energy, and Angular Momentum Fluxes during Capillary Disintegration of a Rotating Jet  

Microsoft Academic Search

On the basis of the energy and momentum conservation laws for the process of disintegration of a rotating cylindrical jet as a capillary continuum, rigorous and outstandingly simple universal equations of disintegration are derived. The Bernoulli equation for a steady-state “stream tube” is shown to have the same form for jet disintegration as well. The effect of capillary–centrifugal self-retardation of

V. V. Krotov



Pharmaceutical applications of shellac: moisture-protective and taste-masking coatings and extended-release matrix tablets.  


Shellac is a natural polymer, which is used as enteric coating material in pharmaceutical applications. The major objective of the present study was to investigate the potential of shellac for other purposes, namely to provide moisture-protective and taste-masking coatings as well as extended-release matrix tablets. The efficiency of shellac to achieve moisture protection and taste masking was compared with that of hydroxypropyl methylcellulose (HPMC), which is most frequently used for these purposes. Shellac-coated tablets showed lower water uptake rates than HPMC-coated systems at the same coating level. The stability of acetylsalicylic acid was higher in tablets coated with shellac compared with HPMC-coated systems, irrespective of the storage humidity. Therefore, lower shellac coating levels were required to achieve the same degree of drug protection. Shellac coatings effectively masked the unpleasant taste of acetaminophen tablets. Compared to HPMC, again lower coating levels were required to achieve similar effects. The resulting drug release in simulated gastric fluid was not significantly altered by the thin shellac coatings, which rapidly ruptured due to the swelling of the coated tablet core. In addition, shellac was found to be a suitable matrix former for extended-release tablets. The latter could be prepared by direct compression or via wet granulation using ethanolic or ammoniated aqueous shellac binder solutions. The resulting drug-release patterns could effectively be altered by varying different formulation and processing parameters. PMID:14570313

Pearnchob, N; Siepmann, J; Bodmeier, R



Large Eddy Simulation Study for Fluid Disintegration and Mixing  

NASA Technical Reports Server (NTRS)

A new modeling approach is based on the concept of large eddy simulation (LES) within which the large scales are computed and the small scales are modeled. The new approach is expected to retain the fidelity of the physics while also being computationally efficient. Typically, only models for the small-scale fluxes of momentum, species, and enthalpy are used to reintroduce in the simulation the physics lost because the computation only resolves the large scales. These models are called subgrid (SGS) models because they operate at a scale smaller than the LES grid. In a previous study of thermodynamically supercritical fluid disintegration and mixing, additional small-scale terms, one in the momentum and one in the energy conservation equations, were identified as requiring modeling. These additional terms were due to the tight coupling between dynamics and real-gas thermodynamics. It was inferred that if these terms would not be modeled, the high density-gradient magnitude regions, experimentally identified as a characteristic feature of these flows, would not be accurately predicted without the additional term in the momentum equation; these high density-gradient magnitude regions were experimentally shown to redistribute turbulence in the flow. And it was also inferred that without the additional term in the energy equation, the heat flux magnitude could not be accurately predicted; the heat flux to the wall of combustion devices is a crucial quantity that determined necessary wall material properties. The present work involves situations where only the term in the momentum equation is important. Without this additional term in the momentum equation, neither the SGS-flux constant-coefficient Smagorinsky model nor the SGS-flux constant-coefficient Gradient model could reproduce in LES the pressure field or the high density-gradient magnitude regions; the SGS-flux constant- coefficient Scale-Similarity model was the most successful in this endeavor although not totally satisfactory. With a model for the additional term in the momentum equation, the predictions of the constant-coefficient Smagorinsky and constant-coefficient Scale-Similarity models were improved to a certain extent; however, most of the improvement was obtained for the Gradient model. The previously derived model and a newly developed model for the additional term in the momentum equation were both tested, with the new model proving even more successful than the previous model at reproducing the high density-gradient magnitude regions. Several dynamic SGS-flux models, in which the SGS-flux model coefficient is computed as part of the simulation, were tested in conjunction with the new model for this additional term in the momentum equation. The most successful dynamic model was a "mixed" model combining the Smagorinsky and Gradient models. This work is directly applicable to simulations of gas turbine engines (aeronautics) and rocket engines (astronautics).

Bellan, Josette; Taskinoglu, Ezgi



An investigation into the in vivo performance variability of pH responsive polymers for ileo-colonic drug delivery using gamma scintigraphy in humans.  


Gastrointestinal performance of tablets coated with pH responsive acrylic polymers (Eudragit) was investigated in human volunteers. Tablet cores were coated with Eudragit S dissolved in ethanol (organic), Eudragit S aqueous dispersion (aqueous), or Eudragit FS aqueous dispersion. Eight fasted volunteers received the tablets in a two-way crossover design-treatment 1: Eudragit S (organic) and Eudragit FS coated tablets; treatment 2: Eudragit S (aqueous) and Eudragit FS coated tablets. Eudragit FS coated tablets were included in both treatments to assess its intra-subject performance. Tablets were radiolabelled and followed by gamma scintigraphy; the disintegration times and positions were recorded. Tablets coated with Eudragit S (aqueous) disintegrated in all volunteers mainly in the proximal to mid small intestine. Eudragit S (organic) tablets failed to disintegrate in three out of eight volunteers, while disintegration was in the ileo-caecal junction and ascending colon in all others. Eudragit FS coated tablets disintegrated in 14 out of the 16 administrations. The Eudragit FS coated tablets that did disintegrate exhibited consistent intra- and inter-subject performance, with the site of disintegration focused on the ileo-caecal junction and ascending colon. These in vivo results correlate better with our published in vitro dissolution data in physiological bicarbonate buffers compared to phosphate buffers. PMID:16917845

Ibekwe, Valentine C; Liu, Fang; Fadda, Hala M; Khela, Mandeep K; Evans, David F; Parsons, Gary E; Basit, Abdul W



Formulation and optimisation of raft-forming chewable tablets containing H2 antagonist  

PubMed Central

Purpose: The purpose of this research work was to formulate raft-forming chewable tablets of H2 antagonist (Famotidine) using a raft-forming agent along with an antacid- and gas-generating agent. Materials and Methods: Tablets were prepared by wet granulation and evaluated for raft strength, acid neutralisation capacity, weight variation, % drug content, thickness, hardness, friability and in vitro drug release. Various raft-forming agents were used in preliminary screening. A 23 full-factorial design was used in the present study for optimisation. The amount of sodium alginate, amount of calcium carbonate and amount sodium bicarbonate were selected as independent variables. Raft strength, acid neutralisation capacity and drug release at 30 min were selected as responses. Results: Tablets containing sodium alginate were having maximum raft strength as compared with other raft-forming agents. Acid neutralisation capacity and in vitro drug release of all factorial batches were found to be satisfactory. The F5 batch was optimised based on maximum raft strength and good acid neutralisation capacity. Drug–excipient compatibility study showed no interaction between the drug and excipients. Stability study of the optimised formulation showed that the tablets were stable at accelerated environmental conditions. Conclusion: It was concluded that raft-forming chewable tablets prepared using an optimum amount of sodium alginate, calcium carbonate and sodium bicarbonate could be an efficient dosage form in the treatment of gastro oesophageal reflux disease. PMID:23580933

Prajapati, Shailesh T; Mehta, Anant P; Modhia, Ishan P; Patel, Chhagan N



Formulation and evaluation of sustained release matrix tablet of rabeprazole using wet granulation technique  

PubMed Central

Introduction: Rabeprazole, a member of substituted benzimidazoles, inhibits the final step in gastric acid secretions. This drug claims to cause fastest acid separation (due to higher pKa), and more rapidly converts to the active species to aid gastric mucin synthesis. The most significant pharmacological action of Rabeprazole is dose dependent suppression of gastric acid secretion; without anticholinergic or H2-blocking action. It completely abolishes the hydrochloric acid secretion as it is powerful inhibitor of gastric acid. Rabeprazole is acid labile and hence commonly formulated as an enteric coated tablet. The absorption of rabeprazole occurs rapidly as soon as tablet leaves the stomach. Aim: In the present study an attempt was made to formulate and evaluate Rabeprazole sustained release matrix tablet using wet granulation technique incorporating various polymers like HPMC-E15, Carbopol934, and sodium carboxymethyl cellulose (CMC). Materials and Methods: The Formulated tablets were evaluated for different physicochemical properties like rheological properties, weight variation, thickness, hardness, % friability, in vitro release studies and drug content. Results: Studies revealed that all the physicochemical parameters comply with the official standards. The in vitro release studies exhibits the release up to 90%, over a prolonged period of time which confirms the extended release profile of formulation, having better bioavailability as well as decreased dosing frequency with reduced doses. Conclusion: The sustained release matrix tablets of rabiprazole shown better bioavailability, efficacy and potency, when compared with official standards. PMID:25035637

Khan, Ruqaiyah; Ashraf, Md Shamim; Afzal, Muhammad; Kazmi, Imran; Jahangir, Mohammed Asadullah; Singh, Rajbala; Chandra, Ramesh; Anwar, Firoz



In vitro release kinetics and bioavailability of gastroretentive cinnarizine hydrochloride tablet.  


An oral sustained release dosage form of cinnarizine HCl (CNZ) based on gastric floating matrix tablets was studied. The release of CNZ from different floating matrix formulations containing four viscosity grades of hydroxypropyl methylcellulose, sodium alginate or polyethylene oxide, and gas-forming agent (sodium bicarbonate or calcium carbonate) was studied in simulated gastric fluid (pH 1.2). CNZ release data from the matrix tablets were analyzed kinetically using Higuchi, Peppas, Weibull, and Vergnaud models. From water uptake, matrix erosion studies, and drug release data, the overall release mechanism can be explained as a result of rapid hydration of polymer on the surface of the floating tablet and formation of a gel layer surrounding the matrix that controls water penetration into its center. On the basis of in vitro release data, batch HP1 (CNZ, HPMC-K100LV, SBC, LTS, and MgS) was subjected to bioavailability studies in rabbits and was compared with CNZ suspension. It was concluded that the greater bioavailability of HP1 was due to its longer retention in the gastric environment of the test animal. Batch no. HP1 of floating tablet in rabbits demonstrated that the floating tablet CNZ could be a 24-h sustained release formulation. PMID:20182827

Nagarwal, Ramesh C; Ridhurkar, Devendra N; Pandit, J K



Development of a multiple-unit tablet containing enteric-coated pellets.  


Film coating of pellets is a common way to design modified-release systems. The aim of this study was to produce a multiple-unit tablet compressed from enteric-coated pellets. The dosage form should comply with Pharmacopoeial demands, especially regarding dissolution, but preferably also all other parameters, including sufficient hardness for packaging procedures. Various approaches, such as using different cushioning excipients, using different enteric coating polymers, changing the tablet shape, and application of an additional protective coating, were employed to develop the dosage form. The final formulation released 9.0?±?1.8% of the drug in an acidic medium and was compliant regarding uniformity of mass, content, and friability, and had a hardness of 59 N. An optimal coating was obtained by mixing two acrylic polymers: relatively brittle Eudragit® L30 D-55 with more flexible Eudragit® FS 30 D. A mixture of Avicel® PH 101 as filler and Kollidon(®) VA 64 as dry binder was found to be optimal as a cushioning excipient. It was found that tablet shape and an additional protective pellet coating of Kollidon(®) VA 64 were the key elements for this development. A biconvex tablet shape was found to approximately halve the release in an acidic medium compared to a round flat-faced tablet. PMID:20088675

Dreu, Rok; Ili?, Ilija; Sr?i?, Stanko



Influence of methacrylic acid and hydroxypropylmethyl cellulose on the tablet properties and in vitro release of dextromethorphan hydrobromide.  


The release of dextromethorphan hydrobromide from matrices containing hydroxypropylmethyl cellulose (HPMC K100LV) and methacrylic acid copolymer (Eudragit L100-55) has been evaluated at different ratios of the polymers. The physicochemical properties (including weight, thickness, crushing strengh, friability and disintegration time) were also determined at 1000, 2000 and 4000 p compression forces. No significant differences in weight uniformity and thickness values were observed between the different formulations. The crushing strength of the tablets increased with increasing compression force and it reached a constant level at 4000 p. The formulations containing only HPMC K100LV resulted in an extended release pattern, however, Eudragit L100-55 alone could not effectively prolong the drug release. A combination of HPMC K100LV and Eudragit L100-55 in a 1:1 ratio at the 40% level provided an almost similar drug release profile than the marketed product. PMID:14703967

Takka, S; Singh Bharaj, S; Sakr, A



Mitochondrial Ca(2+) influx targets cardiolipin to disintegrate respiratory chain complex II for cell death induction.  


Massive Ca(2+) influx into mitochondria is critically involved in cell death induction but it is unknown how this activates the organelle for cell destruction. Using multiple approaches including subcellular fractionation, FRET in intact cells, and in vitro reconstitutions, we show that mitochondrial Ca(2+) influx prompts complex II of the respiratory chain to disintegrate, thereby releasing an enzymatically competent sub-complex that generates excessive reactive oxygen species (ROS) for cell death induction. This Ca(2+)-dependent dissociation of complex II is also observed in model membrane systems, but not when cardiolipin is replaced with a lipid devoid of Ca(2+) binding. Cardiolipin is known to associate with complex II and upon Ca(2+) binding coalesces into separate homotypic clusters. When complex II is deprived of this lipid, it disintegrates for ROS formation and cell death. Our results reveal Ca(2+) binding to cardiolipin for complex II disintegration as a pivotal step for oxidative stress and cell death induction. PMID:24948011

Hwang, M-S; Schwall, C T; Pazarentzos, E; Datler, C; Alder, N N; Grimm, S



21 CFR 520.62 - Aminopentamide hydrogen sulphate tablets.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Aminopentamide hydrogen sulphate tablets. 520.62 Section...ANIMAL DRUGS § 520.62 Aminopentamide hydrogen sulphate tablets. (a) Chemical name...Dimethylamino)-2,2-diphenylvaleramide hydrogen sulfate. (b) Specifications....



SANCTUARY : asymmetric interfaces for game-based tablet learning  

E-print Network

This thesis describes the production of Sanctuary, a multiplayer learning game to be played on two tablet computers. Sanctuary's principle innovation is the splitting of the user interface onto two tablets, separating ...

Haas, Jason M. (Jason Matthew)



Interpretation of Benefit-Risk of Enoxaparin as Comparator in the RECORD Program: Rivaroxaban Oral Tablets (10 milligrams) for Use in Prophylaxis in Deep Vein Thrombosis and Pulmonary Embolism in Patients Undergoing Hip or Knee Replacement Surgery  

Microsoft Academic Search

The Regulation of Coagulation in Major Orthopedic surgery reducing the Risk of DVT and PE (RECORD) clinical program of rivaroxaban consists of 4 phase III clinical trials comparing rivaroxaban with enoxaparin for the prevention of venous thromboembolism (VTE) in patients undergoing either total hip or total knee replacement surgery. Despite the comprehensive and extensive nature of this program, it had

David Van Thiel; Evi Kalodiki; Rakesh Wahi; Evan Litinas; Wasimul Haque; Gundu Rao



Zero-order release of aspirin, theophylline and atenolol in water from novel methylcellulose glutarate matrix tablets.  


A novel hydrocolloidal polymer, methylcellulose glutarate (MC-GA), was prepared by esterifying methylcellulose with glutaric anhydride. The formation of ester was confirmed by FTIR and NMR spectroscopy, DSC and elemental analysis. The physicochemical properties such as, rate of swelling in water, viscosity and hygroscopicity of MC-GA were determined and compared with those of methycellulose A (MC). Aspirin, theophylline and atenolol tablets were compacted on a Carver press using the wet granulation method. Each tablet contained: 200 mg active, 80 mg anhydrous lactose, 8 mg povidone, 4 mg magnesium stearate, 4 mg talc, 50mg MC or MC-GA (drug-to-polymer ratio, 4:1). Contrary to the first-order release profile of all the drugs from the MC matrix tablets, a zero-order release was obtained from the MC-GA matrix tablets in water. PMID:16621361

Khairuzzaman, A; Ahmed, S U; Savva, M; Patel, N K



Stability study of losartan/hydrochlorothiazide tablets.  


The purpose of stability testing is to investigate how the quality of a drug product changes with time under the influence of environmental factors, to establish a shelf life for the product and to recommend storage conditions. Stability study of losartan/hydrochlorothiazide tablets is presented in this paper. Losartan (angiotensin II receptor antagonist) and hydrochlorothiazide (diuretic) are successfully used in association in the treatment of hypertension. Stability study of losartan/hydrochlorothiazide tablets consisted of three steps: stress test (forced degradation study), preliminary testing (selection of packaging) and formal stability testing. The results of stress test suggested that losartan/hydrochlorothiazide tablets are sensitive to moisture. It was demonstrated that the developed analytical methods are stability indicating. Additional preliminary testing was performed in order to select appropriate packaging for losartan/hydrochlorothiazide tablets. OPA/Al/PVC//Al blisters were found to provide adequate protection for the product. Based on the first 12 months of the formal stability study, a shelf life of 24 months was proposed. Losartan/hydrochlorothiazide tablets in OPA/Al/PVC//Al blisters are demonstrated to be chemically, physically and microbiologically stable. PMID:15707739

Lusina, Maja; Cindri?, Tanja; Tomai?, Jadranka; Peko, Marijana; Pozai?, Lidija; Musulin, Nenad



Molecular dynamic simulations of ocular tablet dissolution.  


Small tablets for implantation into the subconjunctival space in the eye are being developed to inhibit scarring after glaucoma filtration surgery (GFS). There is a need to evaluate drug dissolution at the molecular level to determine how the chemical structure of the active may correlate with dissolution in the nonsink conditions of the conjunctival space. We conducted molecular dynamics simulations to study the dissolution process of tablets derived from two drugs that can inhibit fibrosis after GFS, 5-fluorouracil (5-FU) and the matrix metalloprotease inhibitor (MMPi), ilomastat. The dissolution was simulated in the presence of simple point charge (SPC) water molecules, and the liquid turnover of the aqueous humor in the subconjunctival space was simulated by removal of the dissolved drug molecules at regular intervals and replacement by new water molecules. At the end of the simulation, the total molecular solvent accessible surface area of 5-FU tablets increased by 60 times more than that of ilomastat as a result of tablet swelling and release of molecules into solution. The tablet dissolution pattern shown in our molecular dynamic simulations tends to correlate with experimental release profiles. This work indicates that a series of molecular dynamic simulations can be used to predict the influence of the molecular properties of a drug on its dissolution profile and could be useful during preformulation where sufficient amounts of the drug are not always available to perform dissolution studies. PMID:24073784

Ru, Qian; Fadda, Hala M; Li, Chung; Paul, Daniel; Khaw, Peng T; Brocchini, Steve; Zloh, Mire



Extracorporeal shock wave lithotripsy of pancreatic duct stones and patient factors related to stone disintegration  

Microsoft Academic Search

Background:\\u000a Background:   Stones in the main pancreatic duct (MPD) are difficult to remove by endoscopic devices alone in some patients who have chronic\\u000a pancreatitis. We treated these patients with extracorporeal shock wave lithotripsy (ESWL) and analyzed the patient factors\\u000a related to disintegration. \\u000a \\u000a \\u000a \\u000a Methods:   Twenty-four patients were treated with ESWL alone or with combined endoscopic-ESWL to disintegrate or remove MPD stones.

Yasuyuki Karasawa; Shigeyuki Kawa; Yuji Aoki; Yasuhide Ochi; Hiroshi Unno; Kendo Kiyosawa; Tomofumi Watanabe



An Evaluation of Some Commercial Test Papers and Tablets for the Determination of Glucose in Urine  

PubMed Central

The commercial test papers, Tes-Tape, Clinistix, Uristix and Combistix, and the tablet preparation, Clinitest, were evaluated as indicators of glucose in urine by means of a quantitative automated glucose oxidase procedure for glucose determination. The semiquantitative Tes-Tape yielded very low values on urine specimens when compared with the quantitative method. More reliable results could be obtained with this product if the urine specimens were first treated with a mixed bed resin to remove inhibitors of the glucose oxidase peroxidase system. The qualitative test papers, Clinistix, Uristix and Combistix, yielded responses in closer agreement with the automated data, the best performance being obtained with Clinistix. The semiquantitative Clinitest tablets generally yielded more accurate results on a direct urine test than did Tes-Tape, although the Clinitest tablet is designed to measure total reducing substances rather than glucose alone. PMID:14175875

Logan, J. E.; Haight, D. E.



Understanding Tablet Use: A Multi-Method Exploration Hendrik Muller  

E-print Network

provides an in-depth pic- ture of frequent tablet activities (e.g., checking emails, play- ing games, social networking), locations of use (e.g., couch, bed, table), and contextual factors (e.g., watching TV, they watch videos, and they play games on their tablets. Existing insights into tablet ownership and use

Tomkins, Andrew


Instructor Use of Tablet PCs in a College Pre-Calculus Course: Implementation & Assessment  

ERIC Educational Resources Information Center

A group of six math instructors used tablet PCs to teach their individual sections of a high enrollment gateway Pre-Calculus course in a diverse urban four-year college. Student performance in the experimental sections were compared to those in 31 other sections in terms of student retention, pass rates, and score on the department-wide…

Connelly Stockton, Julianna; Gregory, Peter



Pharmacokinetic and Safety Analyses of Tenofovir and Tenofovir-Emtricitabine Vaginal Tablets in Pigtailed Macaques  

PubMed Central

Vaginal rapidly disintegrating tablets (RDTs) containing tenofovir (TFV) or TFV and emtricitabine (FTC) were evaluated for safety and pharmacokinetics in pigtailed macaques. Two separate animal groups (n = 4) received TFV (10 mg) or TFV-FTC (10 mg each) RDTs, administered near the cervix. A third group (n = 4) received 1 ml TFV gel. Blood plasma, vaginal tissue biopsy specimens, and vaginal fluids were collected before and after product application at 0, 0.5, 1, 4, and 24 h. A disintegration time of <30 min following vaginal application of the RDTs was noted, with negligible effects on local inflammatory cytokines, vaginal pH, and microflora. TFV pharmacokinetics were generally similar for both RDTs and gel, with peak median concentrations in vaginal tissues and vaginal secretions being on the order of 104 to 105 ng/g (147 to 571 ?M) and 106 ng/g (12 to 34 mM), respectively, at 1 to 4 h postdose. At 24 h, however, TFV vaginal tissue levels were more sustained after RDT dosing, with median TFV concentrations being approximately 1 log higher than those with gel dosing. FTC pharmacokinetics after combination RDT dosing were similar to those of TFV, with peak median vaginal tissue and fluid levels being on the order of 104 ng/g (374 ?M) and 106 ng/g (32 mM), respectively, at 1 h postdose with levels in fluid remaining high at 24 h. RDTs are a promising alternative vaginal dosage form, delivering TFV and/or FTC at levels that would be considered inhibitory to simian-human immunodeficiency virus in the macaque vaginal microenvironment over a 24-h period. PMID:24566178

Pereira, Lara E.; Friend, David R.; Garber, David A.; McNicholl, Janet M.; Hendry, R. Michael; Doncel, Gustavo F.



Hypocitraturia despite potassium citrate tablet supplementation.  


Citrate supplementation is widely used in the prevention of recurrent nephrolithiasis with hypocitraturia. Potassium citrate is the most commonly used citrate agent for this indication. In patients with chronic diarrheal syndromes, the absorption of potassium citrate can be affected. We describe a patient who presented with recurrent nephrolithiasis and chronic diarrhea and was found to have severe hypocitraturia despite citrate supplementation with potassium citrate tablets, likely due to inadequate gastrointestinal absorption of citrate from the slow-release wax-matrix tablets. PMID:17406150

Shenoy, Chetan



Interpretation of benefit-risk of enoxaparin as comparator in the RECORD program: rivaroxaban oral tablets (10 milligrams) for use in prophylaxis in deep vein thrombosis and pulmonary embolism in patients undergoing hip or knee replacement surgery.  


The Regulation of Coagulation in Major Orthopedic surgery reducing the Risk of DVT and PE (RECORD) clinical program of rivaroxaban consists of 4 phase III clinical trials comparing rivaroxaban with enoxaparin for the prevention of venous thromboembolism (VTE) in patients undergoing either total hip or total knee replacement surgery. Despite the comprehensive and extensive nature of this program, it had some logistic issues that included the dosing of the enoxaparin which was not only inconsistent with the recommendations but the dosages used were not optimal. The duration of treatment while consistent with rivaroxaban did vary with enoxaparin and was somewhat short. The bleeding definitions and safety evaluations were not consistent in accordance with the current recommendations. Moreover, the RECORD program has no power to show differences in major bleeding. The cardiovascular rebound phenomenon should have been adequately addressed and may require additional clinical validation to establish the safety of rivaroxaban. Although the US Food and Drug Administration (FDA) advisory committee has recommended approval of rivaroxaban, the reported analysis strongly suggests additional clinical validation on the claimed benefit/risk ratio of this monotherapeutic anticoagulant. PMID:19608550

Van Thiel, David; Kalodiki, Evi; Wahi, Rakesh; Litinas, Evan; Haque, Wasimul; Rao, Gundu



Knowledge DisIntegration: A neglected process in the Organizational Knowledge Debate?  

Microsoft Academic Search

Abstract This paper introduces a fresh ,perspective to ,the current Knowledge ,Management debate by exploring ,Knowledge ,Integration and ,Dis-integration practices. These issues are relatively under-researched in ,studies of organisational knowledge ,even though,issues of integration ,seem ,to underpin ,most of the ,knowledge ,processes

Elena P. Antonacopoulou; Stephanie Geary; Efrosyni Konstantinou



Paleontological Society Experimental Disintegration of Regular Echinoids: Roles of Temperature, Oxygen, and Decay  

E-print Network

Paleontological Society Experimental Disintegration of Regular Echinoids: Roles of Temperature. 16, No. 3 (Summer, 1990), pp. 247-271 Published by: Paleontological Society Stable URL: Paleontological Society is collaborating with JSTOR to digitize, preserve and extend access to Paleobiology. http

Boyce, C. Kevin


Lord of the Flies Community College: A Case Study of Organizational Disintegration.  

ERIC Educational Resources Information Center

An interpretive case study examines the organizational disintegration of a community college that experienced a sudden loss of leadership, focusing on how its culture both contributed to and prevented organizational chaos. It addresses how leaders can honor the culture and mission of educational organizations and simultaneously work to transform…

Cooper, Joanne; Kempner, Ken



Determination of 129 I in large soil samples after alkaline wet disintegration  

Microsoft Academic Search

Large soil samples (up to 500 g) can conveniently be disintegrated by hydrogen peroxide in an utility tank under alkaline conditions to determine subsequently 129I by neutron activation analysis. Interfering elements such as Br are removed already before neutron irradiation to reduce the radiation exposure of the personnel. The precision of the method is 129I also by the combustion method.

K. Bunzl; W. Kracke



Disintegration of sedimentary rocks used as building material: evaluation and quantification in 4D  

Microsoft Academic Search

Many natural building stones are subject to weathering processes that may lead to their disintegration. When rocks are exposed to extreme exogenous factors such as a combination of water and freeze-thaw cycles, they can deteriorate and cause problems concerning the maintenance of the structure. Some rock types are more susceptible to weathering processes than others, in which fluctuating environmental factors

J. Dewanckele; M. A. Boone; T. de Kock; V. Cnudde; M. N. Boone; Y. de Witte; K. Pieters; D. van Loo; L. van Hoorebeke; P. Jacobs



The Production by Certain Species of Clostridium of Enzymes Disintegrating Hide Powder  

Microsoft Academic Search

SUMMARY: The production by certain species of Clostridiwn of enzymes disintegrating hide powder was investigated by measuring the lytic action of broth cultures and toxic filtrates on finely divided hide powder suspended in an agar gel. Cl. histolyticum was the most active producer of enzyme, Cl. welchii A was less active and Cl. sporogenes and Cl. bifermentnns only moderately active.




Expression of the Transcriptional Repressor Protein Kid-1 Leads to the Disintegration of the Nucleolus*  

E-print Network

Expression of the Transcriptional Repressor Protein Kid-1 Leads to the Disintegration, Massachusetts 02129 The rat Kid-1 gene codes for a 66-kDa protein with KRAB domains at the NH2 terminus and two a biochemical and functional analysis of the Kid-1 protein in transfected cells. The full-length Kid-1 protein

Witzgall, Ralph - Naturwissenschaftliche Fakultät III


American Journal of Botany 88(2): 348361. 2001. DISINTEGRATION OF THE SCROPHULARIACEAE1  

E-print Network

348 American Journal of Botany 88(2): 348­361. 2001. DISINTEGRATION OF THE SCROPHULARIACEAE1 AND PATRICK A. REEVES3 3 Department of Botany, Box 355325, University of Washington, Seattle, Washington 98195 78212 USA; and 7 Department of Botany and Microbiology, University of Oklahoma, 770 Van Vleet Oval

Olmstead, Richard


Psychiatrist Availability, Social Disintegration, and Suicide Deaths in U.S. Counties, 1990-1995  

ERIC Educational Resources Information Center

Previous studies have found that primary care resources are associated with various health outcomes. The primary purpose of the study was to test for associations between psychiatrist availability, social disintegration and suicide rates. Data utilized were from the 2002 Area Resource File on U.S. counties (N=3080). Suicide rates were averaged…

Kposowa, Augustine J.



"The disintegration of organic compounds by microorganisms is accompanied by the liberation of  

E-print Network

"The disintegration of organic compounds by microorganisms is accompanied by the liberation of electrical energy." M.C. Potter, 1911. It is well known that microorganisms can produce fuels, such as ethanol, methane and hydrogen, from organic matter. It is less well known that microorganisms can also

Lovley, Derek


Kazimierz Dabrowski's Theory of Positive Disintegration and the American Humanistic Psychology.  

ERIC Educational Resources Information Center

Discusses the differences and similarities between Dabrowski's theory of positive disintegration and the theories of the American humanistic psychologists. Stresses the suffering associated with attaining higher levels of spiritual development. Suggests that Dabrowski and humanists followed different theodicies. (Author/ABL)

Weckowicz, T. E.



Dabrowski without the Theory of Positive Disintegration Just Isn't Dabrowski  

ERIC Educational Resources Information Center

Dabrowski's theory of positive disintegration (K. Dabrowski, 1964, 1967, 1970, 1972, 1973) has been the subject of a number of research projects in the gifted field over the past 20 or so years. Most of this research has focused on Dabrowski's idea of overexcitability and has not discussed the broader context or implications of his theory or…

Tillier, William



The Essential Elements of Dabrowski's Theory of Positive Disintegration and How They Are Connected  

ERIC Educational Resources Information Center

The purpose of this article is to present Dabrowski's theory of positive disintegration (TPD; Dabrowski, 1964) in a thorough and accessible manner so that those in the gifted community can better understand it and its usefulness to the field of gifted studies. The article goes beyond what has typically been presented in recent research literature…

Ackerman, Cheryl M.



Evaluation of novel immediate-/controlled-release tablets of isosorbide-5-mononitrate (5-ISMN): in vitro-in vivo correlation.  


The aim of the present study was to develop the novel immediate-controlled release (ICR) tablets of isosorbide-5-mononitrate (5-ISMN) composed of an osmotic pump tablet core coated with an immediate-release layer. The novel ICR tablets of 5-ISMN could release drug quickly and continuously through a semi-permeable membrane (SPM) composed of ethylcellulose (EC)/polyethylene glycol (PEG) 4000 and cellulose acetate (CA)/PEG4000. Release tended to decrease with storage time. However, the drug release rates changed little for the SPM composed of EC/PVP K30. The weight loss test also confirmed these results. The major release mechanism was diffusion according to the Higuchi equation. The relative bioavailability of the ICR tablets compared to the reference formulation in the single and multiple dose regiments were 90.9 and 111.2%, respectively. They were both bioequivalent to the reference formulation. In vitro-in vivo correlation (IVIVC) studies demonstrated that the dissolution in vitro simulated the absorption in vivo well. In general, 5-ISMN ICR tablets composed of an osmotic pump tablet core and an immediate-release layer may be promising in providing immediate and constant drug delivery with minimum fluctuations during long storage time. PMID:24640599

Li, Xin; Jiang, Qingwei; Du, Lina; Li, Ying; Li, Miao



Drug release characteristics from chitosan-alginate matrix tablets based on the theory of self-assembled film.  


The aim of this study was to better understand the underlying drug release characteristics from chitosan-alginate matrix tablets containing different types of drugs. Theophylline, paracetamol, metformin hydrochloride and trimetazidine hydrochloride were used as model drugs exhibiting significantly different solubilities (12, 16, 346 and >1000 mg/ml at 37 °C in water). A novel concept raised was that drugs were released from chitosan-alginate matrix tablets based on the theory of a self-assembled film-controlled release system. The film was only formed on the surface of tablets in gastrointestinal environment and originated from chitosan-alginate polyelectrolyte complex, confirmed by differential scanning calorimetry characterization. The formed film could decrease the rate of polymer swelling to a degree, also greatly limit the erosion of tablets. Drugs were all released through diffusion in the hydrated matrix and polymer relaxation, irrespective of the drug solubility. The effects of polymer level and initial drug loading on release depended on drug properties. Drug release was influenced by the change of pH. In contrast, the impact of ionic strength of the release medium within the physiological range was negligible. Importantly, hydrodynamic conditions showed a key factor determining the superiority of the self-assembled film in controlling drug release compared with conventional matrix tablets. The new insight into chitosan-alginate matrix tablets can help to broaden the application of this type of dosage forms. PMID:23624081

Li, Liang; Wang, Linlin; Shao, Yang; Ni, Rui; Zhang, Tingting; Mao, Shirui



Enhanced bioavailability of buspirone hydrochloride via cup and core buccal tablets: formulation and in vitro/in vivo evaluation.  


This work aims to prepare sustained release buccal mucoadhesive tablets of buspirone hydrochloride (BH) to improve its systemic bioavailability. The tablets were prepared according to 5×3 factorial design where polymer type was set at five levels (carbopol, hydroxypropyl methylcellulose, sodium alginate, sodium carboxymethyl cellulose and guar gum), and polymer to drug ratio at three levels (1:1, 2:1 and 3:1). Mucoadhesion force, ex vivo mucoadhesion time, percent BH released after 8 h (Q8h) and time for release of 50% BH (T(??%)) were chosen as dependent variables. Additional BH cup and core buccal tablets were prepared to optimize BH release profile and make it uni-directional along with the tablets mucoadhesion. Tablets were evaluated in terms of content uniformity, weight variation, thickness, diameter, hardness, friability, swelling index, surface pH, mucoadhesion strength and time and in vitro release. Cup and core formula (CA10) was able to adhere to the buccal mucosa for 8h, showed the highest Q8h (97.91%) and exhibited a zero order drug release profile. Pharmacokinetic study of formula CA10 in human volunteers revealed a 5.6 fold increase in BH bioavailability compared to the oral commercial Buspar® tablets. Conducting level A in vitro/in vivo correlation showed good correlation (r²=0.9805) between fractions dissolved in vitro and fractions absorbed in vivo. PMID:24412520

Kassem, Mohamed A A; Elmeshad, Aliaa N; Fares, Ahmed R



The ACTION study: a randomized, open-label, multicenter trial comparing once-a-day extended-release morphine sulfate capsules (AVINZA) to twice-a-day controlled-release oxycodone hydrochloride tablets (OxyContin) for the treatment of chronic, moderate to severe low back pain.  


This large, open-label, randomized, parallel-group, multicenter study compared two oral sustained-release opioids (SROs)--AVINZA (A-MQD), morphine sulfate extended-release capsules given once a day, and OxyContin (O-ER), oxycodone modified-release tablets given twice a day--in SRO-naive subjects ages 30 to 70 with chronic, moderate to severe low back pain. Of the 392 subjects enrolled and randomized, 266 (132 in the A-MQD group and 134 in the O-ER group) completed the opioid dose titration phase and entered an eight-week evaluation phase. During the evaluation phase, A-MQD achieved significantly better pain control than O-ER, as demonstrated by a greater decrease from baseline in pain scores obtained four times daily during weeks one, four, and eight (p = 0.002). The number of breakthrough-pain rescue medication doses adjusted for the number of patient days was significantly lower in the A-MQD group (p < 0.0001). Better pain control with A-MQD was achieved with a significantly lower daily opioid dose than with O-ER (mean 69.9 mg and 91 mg morphine equivalents, respectively; p = 0.0125). Quality of sleep was significantly better with A-MQD for the entire evaluation phase (p = 0.0026). The incidence and severity of elicited opioid side effects were similar in the two groups. This trial demonstrated that once-daily A-MQD provides consistent around-the-clock pain relief in patients with low back pain. In patients who completed opioid dose titration, A-MQD was significantly better than O-ER for reducing pain and improving sleep, while requiring a lower daily opioid dose. PMID:17319449

Rauck, Richard L; Bookbinder, Stephen A; Bunker, Timothy R; Alftine, Christopher D; Ghalie, Richard; Negro-Vilar, Andres; de Jong, Egbert; Gershon, Steven



Novel chewable sustained-release tablet containing verapamil hydrochloride.  


The aim of this research is to produce a compactable self-sealing chewable tablet of verapamil hydrochloride. Tablets were prepared by compressing beads coated with multiple layers including drug, hydroxypropyl methylcellulose, polyethylene oxide, ethylcellulose, lactose, and sodium starch glycolate. Dissolution studies were carried out according to the USP XXII paddle method for 14 h. A new tablet formulation was evaluated in three different forms: 1) whole tablet, 2) crushed tablet using a commercial tablet crusher, and 3) tablet chewed in the mouth and then expelled into dissolution fluid. Sustained release from the new formulation was maintained and was similar in all three different treatments, and similar to drug release from intact commercially available Isoptin SR, but crushing or chewing destroyed the sustained release property of Isoptin SR (as expected). This new formulation can be administered either by swallowing the whole tablet or by first crushing or chewing the tablet. Controlled release properties of this new formulation do not change by chewing or crushing the tablet first. Such a tablet could be valuable for all patients including those who have difficulty swallowing, such as pediatrics and geriatrics. PMID:15202577

El-Gazayerly, Omaima N; Rakkanka, Vipaporn; Ayres, James W



Liquisolid technique as a new approach to sustain propranolol hydrochloride release from tablet matrices.  


It is suggested here that liquisolid technique has the potential to be optimized for the reduction of drug dissolution rate and thereby production of sustained release systems. In the present study, propranolol hydrochloride was dispersed in polysorbate 80 as the liquid vehicle. Then a binary mixture of carrier-coating materials (Eudragit RL or RS as the carrier and silica as the coating material) was added to the liquid medication under continuous mixing in a mortar. The final mixture was compressed using the manual tableting machine. The effect of drug concentration, loading factor, thermal treating and aging on release profile of propranolol hydrochloride from liquisolid compacts were investigated at two pH values (1.2 and 6.8). The release rate of propranolol HCl from liquisolid compacts was compared to the release of propranolol HCl from conventional tablets. X-ray crystallography and DSC were used to investigate the formation of any complex between drug and excipients or any crystallinity changes during the manufacturing process. Propranolol HCl tablets prepared by liquisolid technique showed greater retardation properties in comparison with conventional matrix tablets. This investigation provided evidence that polysorbate 80 (Tween 80) has important role in sustaining the release of drug from liquisolid matrices, and a reduction of T(g) of the polymer can be the reason for the release prolongation of liquisolid tablets. The results also showed that wet granulation had remarkable impact on release rate of propranolol HCl from liquisolid compacts, reducing the release rate of drug from liquisolid compacts. The results showed that aging (liquisolid tablets were kept at 25 degrees C/75% relative humidity for 6 months) had no effect on hardness and dissolution profile of drug. The kinetics studies revealed that most of the liquisolid formulations followed the zero-order release pattern. X-ray crystallography and DSC ruled out any changes in crystallinity or complex formation during the manufacturing process of liquisolid formulations. PMID:18647643

Javadzadeh, Yousef; Musaalrezaei, Leila; Nokhodchi, Ali



A Comparison of Tablet Computer and Paper-Based Questionnaires in Healthy Aging Research  

PubMed Central

Background Digital questionnaire delivery offers many advantages to investigators and participants alike; however, evidence supporting digital questionnaire delivery via touchscreen device in the older adult population is lacking. Objective The objective of this study was to compare the use of tablet computer-delivered and printed questionnaires as vehicles for the collection of psychosocial data from older adults to determine whether this digital platform would be readily adopted by the sample, and to identify whether tablet delivery influences the content of data received. Methods The participants completed three questionnaires using both delivery methods, followed by a brief evaluation. Results A nonparametric one-sample binomial test indicated a significantly greater proportion of individuals preferred the tablet-delivered questionnaires (z=4.96, SE 3.428, P<.001). Paired sample t tests and Wilcoxon sign-rank tests indicated that measures collected by each method were not significantly different (all P?.273). Ease of use of the tablet interface and anxiety while completing the digital questionnaires were significantly correlated with preferences, (r s=.665, P<.001 and r s=.552, P<.001, respectively). Participants most frequently reported that the tablet delivery increased speed of use and improved data entry, although navigation was perceived as being more difficult. By comparison, participants felt that the paper packet was easier to read and navigate, but was slow and cumbersome, and they disliked the lack of dynamic features. Conclusions This study provides preliminary evidence suggesting that questionnaires delivered to older adults using contemporary tablet computers may be acceptable and do not substantively influence the content of the collected data. PMID:25048799

McAuley, Edward



Objective color classification of ecstasy tablets by hyperspectral imaging.  


The general procedure followed in the examination of ecstasy tablets for profiling purposes includes a color description, which depends highly on the observers' perception. This study aims to provide objective quantitative color information using visible hyperspectral imaging. Both self-manufactured and illicit tablets, created with different amounts of known colorants were analyzed. We derived reflectance spectra from hyperspectral images of these tablets, and successfully determined the most likely colorant used in the production of all self-manufactured tablets and four of five illicit tablets studied. Upon classification, the concentration of the colorant was estimated using a photon propagation model and a single reference measurement of a tablet of known concentration. The estimated concentrations showed a high correlation with the actual values (R(2) = 0.9374). The achieved color information, combined with other physical and chemical characteristics, can provide a powerful tool for the comparison of tablet seizures, which may reveal their origin. PMID:23683098

Edelman, Gerda; Lopatka, Martin; Aalders, Maurice



Digoxin tablets--a review of the bioavailability problems.  


A review is presented of the more significant aspects of recent bioavailability studies on digoxin tablets that have led to the identification of variations among commercially available tablets and of the correlation of the methods commonly used in such bioavailability evaluations. Pharmacopeial requirements for tablet-to-tablet uniformity of content do not automatically yield uniformity of bioavailability. In vitro dissolution rate of digoxin tablets generally has been shown to correlate with in vivo bioavailability, and this has led to new governmental and pharmacopeial requirements for digoxin tablets. However, some recent reports have shown that in vitro dissolution rate may not always correlate well with bioavailability. The relevance and significance of digoxin tablet bioavailability to clinical effects and therapeutics are briefly discussed. PMID:1266866

Sim, S K



Formulation and in vitro and in vivo evaluation of film-coated montelukast sodium tablets using Opadry® yellow 20A82938 on an industrial scale  

PubMed Central

Purpose: The aim of this study was to formulate stable film-coated montelukast sodium (MS) tablets using Opadry® yellow 20A82938 (Montikast® tablets) and to evaluate their in vitro and in vivo release profile. Methods: MS core tablets were manufactured using a direct compression method. Opadry yellow 20A82938 aqueous coating dispersion was used as the film-coating material. Dissolution of the film-coated tablets was tested in 900 mL of 0.5% sodium lauryl sulfate solution and the bioequivalence of the tablets was tested by comparing them with a reference formulation – Singulair® tablets. In vitro–in vivo correlation was evaluated. The stability of the obtained film-coated tablets was evaluated according to International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines. Results: The efficiency of the film coating was determined by subjecting the coated tablets to gastric pH and drug release was analyzed using high-performance liquid chromatography. The coated tablets had no obvious defects. MS release met the study criterion of not less than 80% dissolved after 30 minutes in 0.5% sodium lauryl sulfate solution. Statistical comparison of the main pharmacokinetic parameters clearly indicated no significant difference between test and reference in any of the calculated pharmacokinetic parameters. Level A correlation between in vitro drug release and in vivo absorption was found to be satisfactory. Conclusion: These findings suggest that aqueous film coating with Opadry yellow 20A82938 is an easy, reproducible, and economical approach for preparing stable MS film-coated tablets without affecting the drug-release characteristics. PMID:23430138

Zaid, Abdel Naser; Natour, Salam; Qaddomi, Aiman; Abu Ghoush, Abeer



Dissolution of tablet-in-tablet formulations studied with ATR-FTIR spectroscopic imaging.  


This work uses ATR-FTIR spectroscopic imaging to study the dissolution of delayed release and pH resistant compressed coating pharmaceutical tablets. Tablets with an inner core and outer shell were constructed using a custom designed compaction cell. The core of the delayed release tablets consisted of hydroxypropyl methylcellulose (HPMC) and caffeine. The shell consisted of microcrystalline cellulose (MCC) and glucose. The core of the pH resistant formulations was an ibuprofen and PEG melt and the shell was constructed from HPMC and a basic buffer. UV/vis spectroscopy was used to monitor the lag-time of drug release and visible optical video imaging was used as a complementary imaging technique with a larger field of view. Two delayed release mechanisms were established. For tablets with soluble shell sections, lag-time was dependent upon rapid shell dissolution. For tablets with less soluble shells, the lag-time was controlled by the rate of dissolution medium ingress through the shell and the subsequent expansion of the wet HPMC core. The pH resistant formulations prevented crystallization of the ibuprofen in the core during dissolution despite an acidic dissolution medium. FTIR imaging produced important information about the physical and chemical processes occurring at the interface between tablet sections during dissolution. PMID:23291036

Wray, Patrick S; Clarke, Graham S; Kazarian, Sergei G



Swelling kinetics of spray-dried chitosan acetate assessed by magnetic resonance imaging and their relation to drug release kinetics of chitosan matrix tablets.  


Magnetic resonance imaging (MRI) was used to assess in situ swelling behaviors of spray-dried chitosan acetate (CSA) in 0.1N HCl, pH 6.8 and pH 5.0 Tris-HCl buffers. The in vitro drug releases from CSA matrix tablets containing the model drugs, diclofenac sodium and theophylline were investigated in all media using USP-4 apparatus. The effect of chitosan molecular weight, especially in pH 6.8 Tris-HCl, was also studied. In 0.1N HCl, the drug release from the matrix tablets was the lowest in relation to the highest swelling of CSA. The swelling kinetics in Tris-HCl buffers are Fickian diffusion according to their best fit to Higuchi's model as well as the drug release kinetics in all the media. The high swelling rate (k(s)(')) was found to delay the drug release rate (k'). The linear relationship between the swelling and fractions of drug release in Tris-HCl buffers was observed, indicating an important role of the swelling on controlling the drug release mechanism. Additionally, CSA of 200 and 800 kDa chitosan did not swell in pH 6.8 Tris-HCl but disintegrated into fractions, and the drug release from the matrix tablets was the highest. PMID:21129484

Huanbutta, Kampanart; Sriamornsak, Pornsak; Limmatvapirat, Sontaya; Luangtana-anan, Manee; Yoshihashi, Yasuo; Yonemochi, Etsuo; Terada, Katsuhide; Nunthanid, Jurairat



Using Tablet Technology for University Lectures  

ERIC Educational Resources Information Center

Tablet PCs provide numerous benefits over traditional electronically projected lectures that use software such as PowerPoint. Flexibility and spontaneity can be achieved by editing or creating notes in real-time. The input pen or stylus is a very useful tool, especially for courses that involve the extensive use of equations or mathematical…

Chester, Victoria



Tablet PC Enhanced Curricula University of Washington  

E-print Network

Tablet PC Enhanced Curricula University of Washington Richard Anderson http://www.cs.washington Classroom Presenter is free for educational and non-commercial use. It is available from: www.cs.washington University of Washington 1. Instructor displays a slide with an exercise

Anderson, Richard



E-print Network

with add-ons to support pen-based input. Digital ink that is input by pen can be stored directly as ABSTRACT Tablet PC's are traditional notebook computers with the ability to process digital ink by writing whiteboard by connecting it to a data projector. The lecture material was archived and accessed

Mock, Kenrick


[Controlled release of prednisolone from suppository prepared using powder of pulverized tablet].  


Prednisolone suppositories have been used successfully for the treatment of ulcerative colitis in hospital settings. However, the raw material of prednisolone suppository, JP prednisolone powder (JP Powder), was recently removed from the market. Therefore we studied the effects of raw material and suppository base on the release of prednisolone suppository for the purpose of designing a new suppository with similar effects to those of suppository prepared using JP powder (old suppository). New suppositories consisting of the powder of pulverized tablet as raw material and Witepsol H-15 and Witepsol E-75 as suppository base were prepared according to the fusion method. Suppository release test was performed by reciprocating dialysis tube method with tapping (RDT method) and dialysis tubing method (DT method). Both RDT method and DT method were performed using a suppository dissolution apparatus (modified JP disintegration apparatus) and a JP15 paddle apparatus, respectively. The test fluid was 50 mM phosphate buffer solution (pH 7.4) maintained at 37+/-0.5 degrees C. The results of release test by RDT method were similar to those of DT method. Release rate of prednisolone from the new suppository was much faster than that of old suppository. The addition of Witepsol E-75 to new suppository base markedly delayed the release of prednisolone from the new suppository. Release rate of prednisolone from the new suppository, consisting of pulverized tablet and Witepsol H-15 and Witepsol E-75 (76:24), corresponded well with that of the old suppository. It was suggested that this suppository could be used as incoming preparation of suppository prepared using JP powder. PMID:18379182

Tatsumi, Akitoshi; Oda, Shoko; Nakamoto, Tomoko; Muraoka, Reiko; Takahashi, Yoshiko; Tanaka, Kuniyoshi; Shikata, Toshiyuki; Tatsumi, Sumiyo; Tagawa, Noriko; Kobayashi, Yoshiharu; Hamaguchi, Tsuneo; Kadobayashi, Muneo



Formulation preference, tolerability and quality of life assessment following a switch from lopinavir\\/ritonavir soft gel capsule to tablet in human immunodeficiency virus-infected patients  

Microsoft Academic Search

BACKGROUND: Lopinavir\\/ritonavir (LPV\\/r) tablet compared to the soft gel capsule (SGC) formulation has no oleic acid or sorbitol, has no refrigeration or food-restriction requirements, and has less pharmacokinetic variability. We compared the tolerability, quality of life (QoL), and formulation preference after switching from LPV\\/r SGC to the tablet formulation. METHODS: In a prospective, single-arm, cohort study-design, 74 human immunodeficiency virus

Ighovwerha Ofotokun; Susan K Chuck; Brian Schmotzer; Kelly L O'Neil



Effects of Lactobacillus salivarius-containing tablets on caries risk factors: a randomized open-label clinical trial  

PubMed Central

Background To evaluate the effects of the lactic acid bacterium Lactobacillus salivarius on caries risk factors. Methods The study was performed in 64 healthy volunteers to evaluate the effects of L. salivarius-containing tablets on caries risk factors. The participants were divided randomly into four groups, and took tablets containing L. salivarius WB21, L. salivarius TI 2711, Ovalgen® DC (antibody against glucosyltransferase from Streptococcus mutans), or xylitol. Levels of mutans streptococci and lactobacilli, amount of salivary flow, salivary pH, and salivary buffering capacity were assessed before and after taking the tablets. Subsequently, a short-term administration trial using L. salivarius WB21-containing tablets was performed in eight healthy volunteers. The participants took L. salivarius WB21-containing tablets (2.0?×?109 colony forming units/day) for 2 weeks, and the numbers of mutans streptococci in saliva were counted. Results The levels of mutans streptococci seemed to decrease in the L. salivarius WB21, TI 2711, and Ovalgen® DC groups compared to the xylitol group, with no significant differences between the groups. Lactobacilli levels significantly increased in the L. salivarius WB21 and TI 2711 groups compared to the other groups. Concerning salivary flow and salivary pH, no significant differences were observed between the groups. The salivary buffering capacity significantly increased in the L. salivarius TI 2711 group (P?=?0.003) and Ovalgen® DC group (P?=?0.002) compared to the xylitol group. The short-term administration trial showed that the L. salivarius WB21-containing tablets significantly decreased the number of mutans streptococci (P?=?0.039). Conclusion L. salivarius-containing tablets were suggested to increase resistance to caries risk factors. Trial registration UMIN000013160 (registration date: February 14, 2014). PMID:25178882



Developing and Validating a Tablet Version of an Illness Explanatory Model Interview for a Public Health Survey in Pune, India  

PubMed Central

Background Mobile electronic devices are replacing paper-based instruments and questionnaires for epidemiological and public health research. The elimination of a data-entry step after an interview is a notable advantage over paper, saving investigator time, decreasing the time lags in managing and analyzing data, and potentially improving the data quality by removing the error-prone data-entry step. Research has not yet provided adequate evidence, however, to substantiate the claim of fewer errors for computerized interviews. Methodology We developed an Android-based illness explanatory interview for influenza vaccine acceptance and tested the instrument in a field study in Pune, India, for feasibility and acceptability. Error rates for tablet and paper were compared with reference to the voice recording of the interview as gold standard to assess discrepancies. We also examined the preference of interviewers for the classical paper-based or the electronic version of the interview and compared the costs of research with both data collection devices. Results In 95 interviews with household respondents, total error rates with paper and tablet devices were nearly the same (2.01% and 1.99% respectively). Most interviewers indicated no preference for a particular device; but those with a preference opted for tablets. The initial investment in tablet-based interviews was higher compared to paper, while the recurring costs per interview were lower with the use of tablets. Conclusion An Android-based tablet version of a complex interview was developed and successfully validated. Advantages were not compromised by increased errors, and field research assistants with a preference preferred the Android device. Use of tablets may be more costly than paper for small samples and less costly for large studies. PMID:25233212

Giduthuri, Joseph G.; Maire, Nicolas; Joseph, Saju; Kudale, Abhay; Schaetti, Christian; Sundaram, Neisha; Schindler, Christian; Weiss, Mitchell G.



Development and optimization of a novel sustained-release dextran tablet formulation for propranolol hydrochloride.  


A novel oral controlled delivery system for propranolol hydrochloride (PPL) was developed and optimized. The in vitro dissolution profiles of sustained-release matrix tablets of racemic PPL were determined and compared with the United States Pharmacopeia (USP) tolerance specifications for Propranolol Hydrochloride Extended-Release Capsules. The influence of matrix forming agents (native dextran, hydroxypropyl methylcellulose (HPMC), cetyl alcohol) and binary mixtures of them on PPL release in vitro was investigated. A central composite design was applied to the optimization of a sustained-release tablet formulation. The sustained-release matrix tablets with good physical, mechanical and technological properties were obtained with a matrix excipient:PPL ratio of 60:40 (w/w), with a dextran:HPMC ratio of 4:1 (w/w) and with a cetyl alcohol amount of 15% (w/w). A comparative kinetic study of the present matrix tablets and commercial SUMIAL RETARD capsules (Spain) was established. The value for the similarity factor (f(2)=69.6) suggested that the dissolution profile of the present two sustained-release oral dosage forms are similar. Higuchi (diffusion) and Hixon-Crowell (erosion) kinetic profiles were achieved and this codependent mechanism of drug release was established. PMID:16584856

Gil, Eddy Castellanos; Colarte, Antonio Iraizoz; Bataille, Bernard; Pedraz, José Luis; Rodríguez, Fernand; Heinämäki, Jyrki



Role of the His-Cys finger of Moloney murine leukemia virus integrase protein in integration and disintegration.  

PubMed Central

Retroviral integrases mediate site-specific endonuclease and transesterification reactions in the absence of exogenous energy. The basis for the sequence specificity in these integrase-viral DNA recognition processes is unknown. Structural analogs of the disintegration substrate were made to analyze the disintegration reaction mechanism for the Moloney murine leukemia virus (M-MuLV) integrase (IN). Modifications in the target DNA portion of the disintegration substrate decreased enzymatic activity, while substitution of the highly conserved CA in the viral long terminal repeat portion had no effect on activity. The role of the His-Cys finger region in catalysis was addressed by N-ethylmaleimide (NEM) modification of the cysteine residues of M-MuLV IN as well as by mutations. Both integration activities, 3' processing, and strand transfer, were completely inhibited by NEM modification of M-MuLV IN, while disintegration activity was only partially sensitive. However, structural analogs of the disintegration substrates that were modified in the target DNA and had the conserved CA removed were not active with NEM-treated M-MuLV IN. In addition, mutants made in the His-Cys region of M-MuLV IN were examined and found to also be completely blocked in integration but not disintegration activity. These data suggest that the domains of M-MuLV IN that are required for the forward integration reaction substrate differ from those required for the reverse disintegration reaction substrate. Images PMID:8350412

Jonsson, C B; Roth, M J



Field studies in architectural acoustics using Tablet PCs  

NASA Astrophysics Data System (ADS)

Core requirements for the sciences within the liberal arts curriculum challenge students to become directly involved in scientific study. These requirements seek to develop scientifically literate leaders and members of society. Formal laboratory periods are not usually associated with these courses. Thus, conceptual discovery and quantitative experimentation must take place outside of the classroom. Physics 115: Musical Technology at Davidson College is such a course and contains a section dealing with architectural acoustics. Field studies in the past have been an awkward and cumbersome activity, especially for non-science majors. The emerging technology of Tablet PCs overcomes many of the problems of mobile data acquisition and analysis, and allows the students to determine the locations of the rooms to be studied. The impulse method for determining reverberation time is used and compared with calculations based on room size and absorption media. The use of Tablet PCs and the publicly available freeware Audacity in field studies investigating architectural acoustics will be discussed. [Work supported in part by the Associated Colleges of the South through their Technology Fellowship program.

Boye, Daniel



Novel gastroretentive sustained-release tablet of tacrolimus based on self-microemulsifying mixture: in vitro evaluation and in vivo bioavailability test  

PubMed Central

Aim: To develop a novel gastroretentive drug delivery system based on a self-microemulsifying (SME) lipid mixture for improving the oral absorption of the immunosuppressant tacrolimus. Methods: Liquid SME mixture, composed of Cremophor RH40 and monocaprylin glycerate, was blended with polyethylene oxide, chitosan, polyvinylpyrrolidone and mannitol, and then transformed into tablets via granulation, with ethanol as the wetting agent. The tablets were characterized in respect of swelling, bioadhesive and SME properties. In vitro dissolution was conducted using an HCl buffer at pH 1.2. Oral bioavailability of the tablets was examined in fasted beagle dogs. Results: The tablet could expand to 13.5 mm in diameter and 15 mm in thickness during the initial 20 min of contact with the HCl buffer at pH 1.2. The bioadhesive strength was as high as 0.98±0.06 N/cm2. The SME gastroretentive sustained-release tablets preserved the SME capability of the liquid SME formations under transmission electron microscope. The drug-release curve was fit to the zero-order release model, which was helpful in reducing fluctuations in blood concentration. Compared with the commercially available capsules of tacrolimus, the relative bioavailability of the SME gastroretentive sustained-release tablets was 553.4%±353.8%. Conclusion: SME gastroretentive sustained-release tablets can enhance the oral bioavailability of tacrolimus with poor solubility and a narrow absorption window. PMID:21927013

Wang, Yan-ping; Gan, Yong; Zhang, Xin-xin



Spontaneous ice-front retreat caused by disintegration of adjacent ice shelf in Antarctica  

NASA Astrophysics Data System (ADS)

Antarctic ice-discharge constitutes the largest uncertainty in future sea-level projections. Floating ice shelves, fringing most of Antarctica, exert retentive forces onto the ice flow. While abrupt ice-shelf retreat has been observed, it is generally considered a localized phenomenon. Here we show that the disintegration of an ice shelf may induce the spontaneous retreat of its neighbor. As an example, we reproduce the spontaneous but gradual retreat of the Larsen B ice front as observed after the disintegration of the adjacent Larsen A ice shelf. We show that the Larsen A collapse yields a change in spreading rate in Larsen B via their connecting ice channels and thereby causes a retreat of the ice front to its observed position of the year 2000, prior to its collapse. This mechanism might be particularly relevant for the role of East Antarctica and the Antarctic Peninsula in future sea level.

Albrecht, Torsten; Levermann, Anders



Kinetics of formation and disintegration of ionic and non-ionic spherical micelles  

NASA Astrophysics Data System (ADS)

Dynamics of self-assembly and structural transitions in amphiphilic systems play an important role in various industrial and biological processes. Main challenge in computational modeling of these dynamics is a complex interplay between various length- and time-scales. In this talk, we discuss development of a multi-scale model for formation and disintegration of non-ionic and ionic spherical micelles. This study is performed under the assumption that the dominant mechanism of micelle formation (disintegration) is a stepwise addition (removal) of individual surfactant monomers to (from) a surfactant aggregate. A series of molecular dynamics simulations is used to develop reduced stochastic models for these elementary processes. It is demonstrated that these processes involve complex interactions of the translational degree of freedom (i.e., distance between centers of mass of the aggregate and the monomer) with degrees of freedom corresponding to the monomer orientation and the micellar shape and microstructure.

Mohan, Gunjan; Kopelevich, Dmitry



Use of hydrophilic natural gums in formulation of sustained-release matrix tablets of tramadol hydrochloride.  


The objective of this work was to develop matrix sustained-release tablets of highly water-soluble tramadol HCl using natural gums (xanthan [X gum] and guar [G gum]) as cost-effective, nontoxic, easily available, and suitable hydrophilic matrix systems compared with the extensively investigated hydrophilic matrices (ie, hydroxypropyl methylcellulose [HPMC]/carboxymethyl cellulose [CMC] with respect to in vitro drug release rate) and hydration rate of the polymers. Matrix tablets of tramadol (dose 100 mg) were produced by direct compression method. Different ratios of 100:0, 80:20, 60:40, 20:80, 0:100 of G gum (or X):HPMC, X gum:G gum, and triple mixture of these polymers (G gum, X gum, HPMC) were applied. After evaluation of physical characteristics of tablets, the dissolution test was performed in the phosphate buffer media (pH 7.4) up to 8 hours. Tablets with only X had the highest mean dissolution time (MDT), the least dissolution efficiency (DE(8)%), and released the drug following a zero-order model via swelling, diffusion, and erosion mechanisms. Guar gum alone could not efficiently control the drug release, while X and all combinations of natural gums with HPMC could retard tramadol HCl release. However, according to the similarity factor (f(2) ), pure HPMC and H(8)G(2) were the most similar formulations to Topalgic-LP as the reference standard. PMID:16584155

Varshosaz, Jaleh; Tavakoli, Naser; Kheirolahi, Fatemeh



Analysis of ecstasy tablets using capillary electrophoresis with capacitively coupled contactless conductivity detection.  


A method for the identification of 3,4-methylenedioxymethamphetamine (MDMA) and meta-chlorophenylpiperazine (mCPP) was developed employing capillary electrophoresis (CE) with capacitively coupled contactless conductivity detection (C(4) D). Sample extraction, separation, and detection of "Ecstasy" tablets were performed in <10 min without sample derivatization. The separation electrolyte was 20 mm TAPS/Lithium, pH 8.7. Average minimal detectable amounts for MDMA and mCPP were 0.04 mg/tablet, several orders of magnitude lower than the minimum amount encountered in a tablet. Seven different Ecstasy tablets seized in Rio de Janeiro, Brazil, were analyzed by CE-C(4) D and compared against routine gas chromatography-mass spectrometry (GC-MS). The CE method demonstrated sufficient selectivity to discriminate the two target drugs, MDMA and mCPP, from the other drugs present in seizures, namely amphepramone, fenproporex, caffeine, lidocaine, and cocaine. Separation was performed in <90 sec. The advantages of using C(4) D instead of traditional CE-UV methods for in-field analysis are also discussed. PMID:25039689

Porto, Suely K S S; Nogueira, Thiago; Blanes, Lucas; Doble, Philip; Sabino, Bruno D; do Lago, Claudimir L; Angnes, Lúcio



Using tablet technology and instructional videos to enhance preclinical dental laboratory learning.  


The purpose of this pilot study was to examine if tablet technology with accompanying instructional videos enhanced the teaching and learning outcomes in a preclinical dental laboratory setting. Two procedures deemed most challenging in Operative Dentistry II were chosen for the development of instructional videos. A random sample of thirty students was chosen to participate in the pilot. Comparison of faculty evaluations of the procedures between the experimental (tablet) and control (no tablet) groups resulted in no significant differences; however, there was a trend toward fewer failures in the experimental group. Examination of the ability to accurately self-assess was compared by exploring correlations between faculty and student evaluations. While correlations were stronger in the experimental group, the control group had significant correlations for all three procedures, while the experimental group had significant correlations on only two of the procedures. Students strongly perceived that the tablets and videos helped them perform better and more accurately self-assess their work products. Students did not support requiring that they purchase/obtain a specific brand of technology. As a result of this pilot study, further development of ideal and non-ideal videos are in progress, and the school will be implementing a "Bring Your Own Device" policy with incoming students. PMID:24489032

Gadbury-Amyot, Cynthia C; Purk, John H; Williams, Brian Joseph; Van Ness, Christopher J



[Comparison of the characteristics of several polymer materials used in hydrophilic matrix tablets].  


Pure and drug hydrophilic matrix tablets were prepared by direct compression method with theophylline as a model drug. The characteristics of four hydrophilic matrix polymers, hydroxypropylmethylcellulose (HPMC), polyethylene oxide (PEO), sodium alginate (NaAlg) and xanthan gum (XG), were compared by investigating the water absorption, swelling, erosion and gel layer strength. The sequence of water absorption rate was XG > NaAlg (H) > PEO > NaAlg (L) > HPMC; The sequence of swelling index was XG > PEO > HPMC > NaAlg; The sequence of erosion rate was NaAlg (L) > NaAlg (H) > PEO80 > PEO200 > PEO300 > XG approximately PEO400 approximately K4M > K15M > PEO600 approximately K100M; The sequence of the gel layer strength was PEO > HPMC > XG > NaAlg. For the PEO and HPMC matrix tablets, with the polymer molecular weight increased, the drug release mechanism was gradually transferred from mainly depending on the erosion to the diffusion; for SAL matrix tablets, the drug release mainly depends on erosion mechanism; and for XG matrix tablets, the drug release mainly depends on non-Fick diffusion mechanism. Comparison of the performance difference between the polymer materials will contribute to rational design and prediction of drug release behaviors from matrix tables and ultimately to achieve clinical needs. PMID:21626791

Nie, Shu-Fang; Liu, Hui; Liu, Yan-Li; Pan, Wei-San



Release of theophylline and carbamazepine from matrix tablets--consequences of HPMC chemical heterogeneity.  


The release of theophylline and carbamazepine from matrix tablets composed of microcrystalline cellulose, lactose and hydroxypropyl methylcellulose (HPMC) was studied. The aim was to investigate the effect of different substituent heterogeneities of HPMC on the drug release from matrix tablets composed of either 35% or 45% HPMC. The release of the poorly soluble carbamazepine was considerably affected by the HPMC heterogeneity, and the time difference at 80% drug release was more than 12h between the formulations of different HPMC batches. This was explained by slower polymer erosion of the heterogeneous HPMC and the fact that carbamazepine was mainly released by erosion. In addition, results from magnetic resonance imaging showed that the rate of water transport into the tablets was similar. This explained the comparable results of the release of the sparingly soluble theophylline from the two formulations even though the polymer erosion and the swelling of the tablets were considerably different. Thus, it can be concluded that the drug release was highly affected by the substituent heterogeneity, especially in the case of carbamazepine, which was released mainly by erosion. PMID:21316446

Viridén, Anna; Abrahmsén-Alami, Susanna; Wittgren, Bengt; Larsson, Anette



Pharmacokinetics and relative bioavailability evaluation of linezolid suspension and tablet formulations.  


The oral liquid formulations poses an alternative way in providing medications to pediatric patients, geriatric patients, patients with feeding tubes, and patients who cannot swallow solid dosage forms. This study was conducted to evaluate the pharmacokinetics (PKs) and relative bioavailability of suspension (reference) and tablet (test) formulations of Linezolid (LZD). In vivo study was established according to a single-center, randomized, single-dose, laboratory-blinded, 2 Way, Cross-Over Study with a washout period of 1-week. Under fasting conditions, 28 healthy Egyptian male volunteers were randomly allocated to receive a single oral dose of either 30 ml LZD or 1 tablet (600 mg LZD) of marketed suspension and tablet formulations. Plasma samples were obtained over a 48-h interval and analyzed for LZD by reversed phase liquid chromatography with ultraviolet detection. The 90% confidence intervals for the ratio of log transformed values of Cmax, AUC0-t, and AUCt-? of the two treatments were within the acceptable range (0.8-1.25) for bioequivalence. From PK perspectives, in this small study in healthy Egyptian adult male volunteers, a single 600 mg dose of the tablet formulation demonstrated comparable rate and extent of absorption to a single 600 mg dose of the suspension formulation based on the US FDA's regulatory definition. No adverse events occurred or were reported after a single 600 mg LZD and both formulations were well tolerated. PMID:23740384

Helmy, S A



Testing lyoequivalency for three commercially sustained-release tablets containing diltiazem hydrochloride.  


In vitro release kinetics of three commercially available sustained release tablets (SR) diltiazem hydrochloride were studied at pH 1.1 for 2 h and for another 6 h at pH 6.8 using the USP dissolution apparatus with the paddle assemble. The kinetics of the dissolution process was studied by analyzing the dissolution data using five kinetic equations: the zero-order equation, the first-order equation, the Higuchi square root equation, the Hixson-Crowell cube root law and the Peppas equation. Analyses of the dissolution kinetic data for diltiazem hydrochloride commercial SR tablets showed that both Dilzacard and Dilzem SR tablets released drug by Non-Fickian (Anomalous transport) release with release exponent (n) equal to 0.59 and 0.54, respectively, which indicate the summation of both diffusion and dissolution controlled drug release. Bi-Tildiem SR tablets released drug by super case II (n = 1.29) which indicate zero-order release due to the dissolution of polymeric matrix and relaxation of the polymer chain. This finding was also in agreement with results obtained from application of zero-order and Hixson-Crowell equations. A dissolution profile comparative study was done to test the lyoequivelancy of the three products by using the mean dissolution time (MDT), dissimilarity factor f1 and similarity factor f2. Results showed that the three products are different and not lyoequivalent. PMID:20210085

Maswadeh, Hamzah A; Al-Hanbali, Othman A; Kanaan, Reem A; Shakya, Ashok K; Maraqa, Anwar



Validated Method for the Determination of Piroxicam by Capillary Zone Electrophoresis and Its Application to Tablets  

PubMed Central

Simple and rapid capillary zone electrophoretic method was developed and validated in this study for the determination of piroxicam in tablets. The separation of piroxicam was conducted in a fused-silica capillary by using 10?mM borate buffer (pH 9.0) containing 10% (v/v) methanol as background electrolyte. The optimum conditions determined were 25?kV for separation voltage and 1?s for injection time. Analysis was carried out with UV detection at 204?nm. Naproxen sodium was used as an internal standard. The method was linear over the range of 0.23–28.79?µg/mL. The accuracy and precision were found to be satisfied within the acceptable limits (<2%). The LOD and LOQ were found to be 0.07 and 0.19?µg/mL, respectively. The method described here was applied to tablet dosage forms and the content of a tablet was found in the limits of USP-24 suggestions. To compare the results of capillary electrophoretic method, UV spectrophotometric method was developed and the difference between two methods was found to be insignificant. The capillary zone electrophoretic method developed in this study is rapid, simple, and suitable for routine analysis of piroxicam in pharmaceutical tablets.

Dal, Ar?n Gul; Oktayer, Zeynep; Dogrukol-Ak, Dilek



Influence of internal structure on kinetics of drug release from wax matrix tablets.  


To examine the influence of the internal structure of a wax matrix tablet on in vitro drug release, the release rates of several tablets consisting of various proportions of drug and wax were compared with the water penetration rates from the compressed and lateral surfaces of the tablets. The penetration rates from the lateral surface were found to be much faster than those from the compressed surface in all cases. A theoretical equation involving a two-dissolving-direction was derived on the basis of the boundary retreating concept. The retreating rate constants deduced from the dissolution results were well coincident with the values directly determined by the needle penetration method, suggesting good applicability of the proposed equation. The results suggest that the tortuosity of the water channels created in a tablet during dissolution is generally smaller in the horizontal direction than that in the vertical direction. This would be caused by the drug particles or granules being elongated in the horizontal direction by compression. PMID:2092942

Ishino, R; Yoshino, H; Hirikawa, Y; Noda, K



In vitro characterization and release study of Ambroxol hydrochloride matrix tablets prepared by direct compression.  


A series of either hydrophilic or hydrophobic polymers were used to prepare controlled release Ambroxol hydrochloride (AMX) matrix tablets by direct compression. Both the compatibility and flow properties of AMX/polymer mixtures were investigated. The effect of the amount and type of polymer on the physical properties and in vitro drug release was studied and compared to commercially available Ambroxol(®) SR capsules. A kinetic study of the release profile of AMX from the prepared matrix tablets was performed. All excipients used in the study were compatible with the model drug. AMX/drug mixtures containing sodium alginate (NA) and hydroxypropylmethyl cellulose (HPMC) showed better flow properties than other polymers used in the study. The in vitro drug release studies showed that matrix tablets formulae containing 10% HPMC (S7) or a combination of 30% NA and 5% HPMC (Ah) exhibited a higher ability to control the release of AMX. The kinetic study revealed that a diffusion controlled mechanism prevailed except when carbopol was used. Formula Ah followed a non-fickian diffusion mechanism similar to Ambroxol(®) SR capsules. Both formulae S7 and Ah could be considered as potential candidates for formulation of AMX controlled release matrix tablets. PMID:21428699

Abd-Elbary, A; Haider, M; Sayed, S



Assessment of xanthan gum based sustained release matrix tablets containing highly water-soluble propranolol HCl.  


The present study was carried out to develop oral sustained release tablets of propranolol HCl by different ratios of drug : matrix. Tablets were prepared by direct compression technique using xanthan gum and lactose. All the formulations (tablets) were evaluated for thickness, diameter, hardness, friability, weight variation, content of active ingredient, in vitro dissolution using USP dissolution apparatus-II and swelling index. In case of dissolution, an inverse relationship was noted between amount of xanthan gum and release rate of propranolol HCl and the drug release was gradually enhanced as the amount of the lactose increased. The direct release was observed between swelling index and xanthan gum concentration. Significant difference in different media was observed in release profile, indicating that propranolol HCI has better solubility in HCI buffer pH 1.2. Moreover, dissolution data at differing stirring speeds was also analyzed, indicating that the drug release profile was at 50 rpm comparative to 100 rpm. The kinetic treatment showed the best fitted different mathematical models (zero order, first order, Higuchi's, Hixson-Crowell and Korsmeyer Peppas model. Most of the formulations showed linearity in Higuchi's model. The drug release from these tablets was by Fickian diffusion and anomalous (non-Fickian) mechanisms. PMID:23614284

Ali, Atif; Iqbal, Muhammad; Akhtar, Naveed; Khan, Haji Muhamad Shoaib; Ullah, Aftab; Uddin, Minhaj; Khan, Muhammad Tahir



Pharmacokinetics of desmopressin administered as tablet and oral lyophilisate formulation in children with monosymptomatic nocturnal enuresis.  


Desmopressin 120 ?g oral lyophilisate and 200 ?g tablet are considered bioequivalent, based on extrapolation of studies in a limited number of adults and on one dose-finding study of desmopressin oral lyophilisate in children. However, no comparative pharmacokinetic study in children was executed confirming this statement. No data are available on the influence of food intake on the bioavailability of desmopressin tablet in a pediatric setting, although studies in adults have documented that food intake results in a significantly lower desmopressin plasma concentration. In this study, we analyzed plasma concentrations of desmopressin oral lyophilisate and tablet with concomitant food intake. Twenty-three children with monosymptomatic nocturnal enuresis (mean age, 12.7 years) were recruited. Two tests were performed on two separate days in identical conditions with a standardized food and fluid intake. Desmopressin was administered as desmopressin tablet or desmopressin oral lyophilisate immediately after a meal. Desmopressin plasma concentration was measured at 1 h, 2 h, and 6 h postdosing. No significant difference in plasma concentration of 120 ?g desmopressin oral lyophilisate and 200 ?g tablet was demonstrated, even with concomitant food intake. A significant difference in variability was found, identifying a smaller variance for desmopressin oral lyophilisate plasma concentrations at all time points. This study demonstrates comparable plasma levels for desmopressin oral lyophilisate, despite the lower dose. The dosage for desmopressin oral lyophilisate is more predictable due to the significantly smaller variance. Therefore, desmopressin oral lyophilisate seems more suitable, especially in the younger age group for which time interval between dinner and drug administration is limited. PMID:23989967

De Bruyne, Pauline; De Guchtenaere, Ann; Van Herzeele, Charlotte; Raes, Ann; Dehoorne, Jo; Hoebeke, Piet; Van Laecke, Erik; Vande Walle, Johan



Randomized controlled trial of sodium phosphate tablets vs polyethylene glycol solution for colonoscopy bowel cleansing  

PubMed Central

AIM: To compare efficacy, patient compliance, acceptability, satisfaction, safety, and adenoma detection rate of sodium phosphate tablets (NaP, CLICOLONTM) to a standard 4 L polyethylene glycol (PEG) solution for bowel cleansing for adults undergoing colonoscopy. METHODS: In this multicenter, randomized, prospective, investigator-blind study, the relatively young (19-60 years) healthy outpatients without comorbidity were randomly assigned to one of two arms. All colonoscopy were scheduled in the morning. The NaP group was asked to take 4 tablets, 5 times the evening before and 4 tablets, 3 times early on the morning of the colonoscopy. The PEG group was asked to ingest 2 L of solution the evening before and 2 L early in the morning of the procedure. Adequacy of bowel preparation was scored using the Boston bowel preparation scale. RESULTS: No significant differences were observed between the NaP group (n = 158) and PEG group (n = 162) in bowel cleansing quality (adequate preparation 93.0% vs 92.6%, P = 0.877), patient compliance (P = 0.228), overall adverse events (63.3% vs 69.1%, P = 0.269), or adenoma detection rate (34.8% vs 35.2%, P = 0.944). Patient acceptability, satisfaction, and patient rating of taste were higher in the NaP group than in the PEG group (P < 0.001). CONCLUSION: NaP tablets, compared with PEG solution, produced equivalent colon cleansing, did not cause more side effects, and had better patient acceptability and satisfaction in the relatively young (age < 60 years) healthy individuals without comorbidity. An oral tablet formulation could make bowel preparation less burdensome, resulting in greater patient participation in screening programs.

Jung, Yoon Suk; Lee, Chang Kyun; Kim, Hyo Jong; Eun, Chang Soo; Han, Dong Soo; Park, Dong Il



77 FR 18860 - Certain Consumer Electronics, Including Mobile Phones and Tablets; Notice of Receipt of Complaint...  

Federal Register 2010, 2011, 2012, 2013

...Consumer Electronics, Including Mobile Phones and Tablets; Notice of Receipt...Consumer Electronics, Including Mobile Phones and Tablets, DN 2885; the Commission...consumer electronics, including mobile phones and tablets. The complaint...



78 FR 47410 - Certain Wireless Devices, Including Mobile Phones and Tablets Institution of Investigation  

Federal Register 2010, 2011, 2012, 2013

...Certain Wireless Devices, Including Mobile Phones and Tablets Institution of Investigation...certain wireless devices, including mobile phones and tablets by reason of infringement...certain wireless devices, including mobile phones and tablets by reason of...



77 FR 24514 - Certain Consumer Electronics, Including Mobile Phones and Tablets; Institution of Investigation...  

Federal Register 2010, 2011, 2012, 2013

...Consumer Electronics, Including Mobile Phones and Tablets; Institution of Investigation...consumer electronics, including mobile phones and tablets, by reason of infringement...consumer electronics, including mobile phones and tablets, that infringe...



78 FR 40171 - Certain Wireless Devices, Including Mobile Phones and Tablets; Notice Of Receipt of Complaint...  

Federal Register 2010, 2011, 2012, 2013

...Certain Wireless Devices, Including Mobile Phones and Tablets; Notice Of Receipt...Certain Wireless Devices, Including Mobile Phones and Tablets, DN 2964; the Commission...certain wireless devices, including mobile phones and tablets. The complaint...



76 FR 24051 - In the Matter of Certain Electronic Devices, Including Mobile Phones, Mobile Tablets, Portable...  

Federal Register 2010, 2011, 2012, 2013

...Mobile Phones, Mobile Tablets, Portable Music Players, and Computers, and phones, mobile tablets, portable music players, and computers, and phones, mobile tablets, portable music players, and computers, and...



78 FR 63228 - Determination That PARAFLEX (Chlorzoxazone) Tablets, 250 Milligrams, Was Not Withdrawn From Sale...  

Federal Register 2010, 2011, 2012, 2013

...That PARAFLEX (Chlorzoxazone) Tablets, 250 Milligrams, Was Not Withdrawn From Sale...that PARAFLEX (Chlorzoxazone) Tablets, 250 milligrams (mg), was not withdrawn from...for PARAFLEX (Chlorzoxazone) Tablets, 250 mg, if all other legal and regulatory...



75 FR 61503 - Determination That AZDONE (Hydrocodone Bitartrate and Aspirin) Tablet, 5 Milligrams/500...  

Federal Register 2010, 2011, 2012, 2013

...That AZDONE (Hydrocodone Bitartrate and Aspirin) Tablet, 5 Milligrams/500 Milligrams...that AZDONE (hydrocodone bitartrate and aspirin) Tablet, 5 milligrams (mg)/ 500 mg...ANDAs) for hydrocodone bitartrate and aspirin tablet, 5 mg/500 mg, if all...



Evolution and final disintegration of spherical stellar systems in a steady galactic tidal field  

Microsoft Academic Search

The dynamical evolution of simplified N-body systems in steady galactic tidal field is followed using an orbit-averaged Fokker-Planck code through core collapse and quasi-static reexpansion phases. The mass of the cluster is found to decrease linearly during the reexpansion phase until the cluster totally disintegrates in a finite time. A modified treatment of tidal losses is presented where mass loss

Hyung Mok Lee; Jeremiah P. Ostriker



Proceedings of Student/Faculty Research Day, CSIS, Pace University, May 5th TabletERD: A Tablet PC Application for Database Design  

E-print Network

in "PowerToys" software [], fun game, art, and multimedia Tablet PC applications. There is a significant market for the development of