Behavior Of Tablets Research Articles

Manufacturing classification system for oral solid dosage forms of traditional Chinese medicines (Ⅱ): classification of tablets disintegration behavior

In this paper, 50 batches of representative traditional Chinese medicine tablets were selected and the disintegration time was examined with the method in Chinese Pharmacopoeia. The disintegration time and disintegration phenomenon were recorded, and the dissolution behaviors of water-soluble and ultraviolet-absorbent components during the disintegration process of tablets were characterized by self-control method. The results revealed that coating type and raw material type influenced the disintegration time of tablets. It was found that only 4% of traditional Chinese medicine tablets had obvious fragmentation during the disintegration process, while 96% of traditional Chinese medicine tablets showed gradual dissolution or dispersion. Furthermore, according to the disintegration speed, disintegration phenomenon, and whether the cumulative dissolution of measured components was > 90% at complete disintegration, a disintegration behavior classification system(DBCS) was created for the regular-release traditional Chinese medicine tablets. As a result, the disintegration behaviors of 50 batches of traditional Chinese medicine tablets were classified into four categories, i.e. ⅠA_2, ⅠB_1, ⅡB_1, and ⅡB_2. traditional Chinese medicine tablets(Class I) with disintegration time ≤ 30 min were defined to be rapid in disintegration, which can be the objective of optimization or improvement of Chinese herbal extract(semi extract) tablets. Different drug release models were used to fit the dissolution curve of traditional Chinese medicine tablets with gradual dissolution or dispersion phenomenon(i.e. Type B tablets). The results showed that the dissolution curves of water-soluble components in the disintegration process conformed to the zero order kinetics and the Ritger-Peppas model. It could be inferred that the disintegration mechanisms of type B tablets were a combination of dissolution controlled and swelling controlled mechanisms. This study contributes to understanding the disintegration behavior of traditional Chinese medicine tablets, and provides a reference for the design and improvement of disintegration performance of traditional Chinese medicine tablets.

Dissociation of gas hydrates in different heating schemes

We present experimental and theoretical research into the dissociation and combustion behavior of methane hydrate tablets and powders of double gas hydrates methane-ethane, methane-isopropanol, and methane-propane using different heat supply schemes. Powder pressing allows significantly changing the porosity, the resistance of gas filtration through the pores, as well as the hydrate dissociation rate. To improve the combustion efficiency, it is necessary to conduct comprehensive studies on use of different schemes of heat supply. In the experiments with pressed tablets of methane hydrate, we observed stable combustion. The double gas hydrate powders showed stable combustion in a muffle furnace. The maximum dissociation rate was observed in the case of a thin (2–3 mm) methane-isopropanol hydrate burned in a muffle furnace. The data obtained for the hydrate dissociation and combustion can help predict the impact of the component composition of gas hydrates and thermal conditions around the samples.

Investigating compressibility descriptors for binary mixtures of different deformation behavior

One of the most important dosage forms remains tablets. Predicting the tableting behavior of formulations is a major goal in the development of those dosage forms. Resources and consequently costs can be saved if time-consuming experiments for empirical formulation development are eliminated. Predicting the properties of a mixture from the properties of the materials it is composed of has been studied many times. To simplify this approach, binary mixtures were tableted in this work. Both pure materials and mixtures in different compositions were characterized with respect to their compressibility and tablet properties. The aim was to investigate different compressibility descriptors for their suitability to predict the tableting behavior of binary mixtures. For this, linear mixing rule for weight and volume fractions was applied to predict the properties of the mixture from the corresponding starting materials. Compressibility analysis, Walker equation and rearrangement index of Kawakita analysis showed promising results. A linear relationship between the compression parameter and the composition of the binary mixture was found for the three parameters. These descriptors can be used as a foundation to describe more complicated mixtures in the future.

Anisotropy Analysis of the Permeation Behavior in Carbon Dioxide-Assisted Polymer Compression Porous Products

The carbon dioxide-assisted polymer compression method is used to create porous polymer products with laminated fiber sheets that are crimped in the presence of carbon dioxide. In this method, fibers are oriented in the sheet-spread direction, and the intersections of the upper and lower fibers are crimped, leading to several intersections within the porous product. This type of orientation in a porous material is anisotropic. A dye solution was injected via a syringe into a compression product made of poly(ethylene terephthalate) nonwoven fabric with an average fiber diameter of 8 μm. The anisotropy of permeation was evaluated using the aspect ratio of the vertical and horizontal permeation distances of a permeation area. The aspect ratio decreased monotonically with decreasing porosity; it was 2.73 for the 80-ply laminated product with a porosity of 0.63 and 2.33 for the 160-ply laminated product with a porosity of 0.25. A three-dimensional structural analysis using X-ray computed tomography revealed that as the compression ratio increased, the fiber-to-fiber connection increased due to the increase in adhesion points, resulting in decreased anisotropy of permeation. The anisotropy of permeation is essential data for analyzing the sustained release behavior of drug-loaded tablets for future fabrication.

Effect of different seed crystals on the supersaturation state of ritonavir tablets prepared by hot-melt extrusion

Hot-melt extrusion (HME) is a technology increasingly common for the commercial production of pharmaceutical amorphous solid dispersions (ASDs), especially for poorly water-soluble active pharmaceutical ingredients (APIs). However, recrystallization of the APIs during dissolution must be prevented to maintain the supersaturation state enabled by ASD. Unfortunately, the amorphous formulation may be contaminated by seed crystals during the HME manufacturing process, which could lead to undesirable crystal growth during the dissolution process. In this study, the dissolution behavior of ritonavir ASD tablets prepared using both Form I and Form II polymorphs was examined, and the effects of different seed crystals on crystal growth rates were investigated. The aim was to understand how the presence of seed crystals can impact the dissolution of ritonavir, and to determine the optimal polymorph and seeding conditions for the production of ASDs. The results showed that both Form I and Form II ritonavir tablets had similar dissolution profiles, which were also similar to the reference listed drug (RLD). However, it was observed that the presence of seed crystals, particularly the metastable Form I seed, led to more precipitation compared to the stable Form II seed in all formulations. The Form I crystals that precipitated from the supersaturated solution were easily dispersed in the solution and could serve as seeds to facilitate crystal growth. On the other hand, Form II crystals tended to grow more slowly and presented as aggregates. The addition of both Form I and Form II seeds could affect their precipitation behaviors, and the amount and form of the seeds had significant effects on the precipitation process of the RLD tablets, as are the tablets prepared with different polymorphs. In conclusion, the study highlights the importance of minimizing the contamination risk of seed crystals during the manufacturing process and selecting the appropriate polymorph for the production of ASDs.

Anionic and Ampholytic High-Amylose Starch Derivatives as Excipients for Pharmaceutical and Biopharmaceutical Applications: Structure-Properties Correlations.

Many chemical modifications of starch are realized in organic (mostly methanol) phase, allowing high degrees of substitution (DS). Some of these materials are used as disintegrants. To expand the usage of starch derivative biopolymers as drug delivery system, various starch derivatives obtained in aqueous phase were evaluated with the aim to identify materials and procedures which would generate multifunctional excipients providing gastro-protection for controlled drug delivery. Chemical, structural and thermal characteristics of anionic and ampholytic High Amylose Starch (HAS) derivatives under powder (P), tablet (T) and film (F) forms were evaluated by X-ray Diffraction (XRD), Fourier Transformed Infrared (FTIR) and thermogravimetric analysis (TGA) methods and correlated with the behavior of tablets and films in simulated gastric and intestinal media. At low DS, the HAS carboxymethylation (CMHAS) in aqueous phase, generated tablets and films that were insoluble at ambient conditions. The CMHAS filmogenic solutions, with a lower viscosity, were easier to cast and gave smooth films without the use of plasticizer. Correlations were found between structural parameters and the properties of starch excipients. Compared to other starch modification procedures, the aqueous modification of HAS generated tunable multifunctional excipients that may be recommended for tablets and functional coatings for colon-targeted formulations.

The preparation, characterization, and application of porous core–shell composite particles produced with laboratory-scale spray dryer

Objective To prepare porous core–shell composite particles (PCPs) in order to improve the flowability and compactibility of powder materials for direct compaction (DC), as well as the dissolution of tablets. Significance The results obtained are meaningful to boosting the development and further research of PCPs on DC. Methods: In this study, hydroxypropyl methylcellulose (HPMC E3) and polyvinylpyrrolidone (PVP K30) were selected as shell materials, the Xiao Er Xi Shi formulation powder (XEXS) was used as the core materials, ammonium bicarbonate (NH4HCO3), and sodium bicarbonate (NaHCO3) were employed as pore-forming agent. Using co-spray drying method to prepare composite particles (CPs). Then, the physical properties and comparison between different CPs were characterized comprehensively. Finally, the different CPs were directly compacted as tablets to explore the effect on the dissolution behavior of DC tablets, respectively. Results (i) The XEXS PCPs were prepared successfully by co-spray drying, and the yield of PCPs is almost 80%; (ii) The TS values of PCP-X-P-Na, PCP-X-P-NH4, PCP-X-H-Na and PCP-X-P-Na were 5.70, 7.56, 3.98, and 6.88 times higher than that of raw material (X); (iii) The disintegration time of PCPs tablets decreased 10–25% when compared with CPs tablets; (iv) The values of Carr’s index (CI), Hausner ratio (HR), Caking strength (CS), and Cohesion index (CoI) of PCP-X-H-NH4 were 19.16%, 19.29%, 40.14%, and 6.39% lower than that of X, respectively. Conclusions The PCPs prepared by co-spray drying did improve the flowability and compactibility of powder, as well as the dissolution of tablets.

Modelling the Evolution of Pore Structure during the Disintegration of Pharmaceutical Tablets

Pharmaceutical tablet disintegration is a critical process for dissolving and enabling the absorption of the drug substance into the blood stream. The tablet disintegration process consists of multiple connected and interdependent mechanisms: liquid penetration, swelling, dissolution, and break-up. One key dependence is the dynamic change of the pore space in a tablet caused by the swelling of particles while the tablet takes up liquid. This study analysed the changes in the pore structure during disintegration by coupling the discrete element method (DEM) with a single-particle swelling model and experimental liquid penetration data from terahertz-pulsed imaging (TPI). The coupled model is demonstrated and validated for pure microcrystalline cellulose (MCC) tablets across three porosities (10, 15, and 22%) and MCC with three different concentrations of croscarmellose sodium (CCS) (2, 5, and 8% w/w). The model was validated using experimental tablet swelling from TPI. The model captured the difference in the swelling behaviour of tablets with different porosities and formulations well. Both the experimental and modelling results showed that the swelling was lowest (i.e., time to reach the maximum normalised swelling capacity) for tablets with the highest CCS concentration, cCCS = 8%. The simulations revealed that this was caused by the closure of the pores in both the wetted volume and dry volume of the tablet. The closure of the pores hinders the liquid from accessing other particles and slows down the overall swelling process. This study provides new insights into the changes in the pore space during disintegration, which is crucial to better understand the impact of porosity and formulations on the performance of tablets.

Effect of pH, Ionic Strength and Agitation Rate on Dissolution Behaviour of 3D-Printed Tablets, Tablets Prepared from Ground Hot-Melt Extruded Filaments and Physical Mixtures

With the current focus on 3D-printing technologies, it is essential to understand the processes involved in such printing methods and approaches to minimize the variability in dissolution behaviour to achieve better quality control outcomes. For this purpose, two formulations of theophylline tablets were prepared using hydroxypropyl cellulose (HPC) and ethyl cellulose (EC). Among the two types of tablets, three different methods (physical mixture (PM), hot-melt extrusion (HME) and 3D-printing fused deposition modelling (FDM)) were applied and their dissolution behaviours were studied under various conditions using a biodissolution tester. This was carried out at pH values of 1.2, 2.2, 5.8, 6.8, 7.2 and 7.5, mimicking the medium in the gastrointestinal tract. Dissolution tests under two dipping rates (10 dpm and 20 dpm) and two ionic strengths (0.2 M and 0.4 M) were conducted to mimic fed and fasting conditions. The dissolution efficiency (DE%), release rate, similarity factor (f2) and difference factor (f1) were calculated. When comparing the DE%, the formulation containing EC showed less sensitivity to changes in the dipping rate and ionic strength compared to the HPC formulation. As for the manufacturing method, 3D-printing FDM could improve the robustness of the dissolution behaviour of both formulations to dipping rate changes. However, for ionic strength changes, the effect of the manufacturing method was dependent on the formulation composition. For example, the 3D-printed tablets of the HPC formulation were more sensitive to changes in ionic strength compared to the EC-containing formulation. The release mechanism also changed after the thermal process, where n values in the Korsmeyer-Peppas model were much higher in the printing and HME methods compared to the PM. Based on the formulation composition, the 3D-printing method could be a good candidate method for tablets with a robust dissolution behaviour in the GI tract. Compared to HPC polymers, using hydrophobic EC polymers in printable formulations can result in a more robust dissolution behaviour in fed and fasting states.

Disk-shaped compact tension test for fracture analysis on pharmaceutical tablets

Pharmaceutical tablets must meet a number of requirements and among them, the mechanical strength plays an important role. The diametral compression test is generally used to evaluate it but can generate unstable failures. Thanks to load-unload cycles applied to the tablets subjected to a DCT test, it was shown that the concept of equivalent linear elastic fracture mechanics usually, can be successfully applied to the Mode I fracture behavior. Within this framework, the equivalent elastic crack growth resistance, commonly called resistance curve (R-curve), of the studied material was obtained and revealed the development of a Fracture Process Zone (FPZ) which is symptomatic of a quasi-brittle behavior. Moreover, the cyclic loading applied during the fracture test revealed the existence of a second dissipative mechanism leading to residual crack opening which seems to be mainly caused by friction phenomenon in the FPZ. • Fracture behavior of pharmaceutical tablets is a key issue for their manufacturing. • An alternative to the diametral compression test is proposed here. • No instability issues using the notch opening displacement controller. • A quasi-brittle behavior identified through equivalent LEFM theory. • Presence of dissipative mechanisms like micro-friction inside the process zone.

Tracking combustion behavior of copper monosulfide, ferrous sulfide, and chalcopyrite tablets by high-speed microscopic videography

A new suspended-combustion-test method involving high-speed digital microscopy and thermal measurements was developed to analyze small tablets of CuS, FeS, and CuFeS2 to elucidate their combustion behavior and phase changes in flash smelting. Moreover, the frequency of splash generation and homogeneous oxidation of the released gaseous sulfur from each sulfide were monitored. Microstructural analysis of quenched samples by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy revealed that the combustion intensity could be related to the formation of an oxide layer, which blocked the O2 supply to the sample interior. Moreover, the gas formed at various oxygen concentrations agitated the samples. In particular, the generated solid-oxide shell could move, the sulfide was exposed to the surface again, and the combustion reaction proceeded further. Insufficient agitation at lower O2 concentrations resulted in a thick and dense oxide layer, which blocked the O2 supply and caused extinction.

The Effectiveness of Health Promotion Strategies for Pregnant Women on Fe Tablet Consumption in the Work Area of Bebesen Health Center, Central Aceh Regency

Background: The distribution coverage of Fe tablets in Bebesen Health Center is still very low, even the lowest compared to other health centers in Central Aceh District, namely 12.40% for Fe1 and 10.56% for Fe3. Failure to achieve the distribution target of Fe tablets in the district can increase the prevalence of anemia. However, there is no clear reporting of anemia in pregnant women, let alone data on adherence to consuming Fe tablets. One of the reasons is the weak monitoring, recording, and reporting system of health workers in consuming Fe tablets and the lack of routine Hb level checks. This study aims to evaluate the effectiveness of health promotion strategies for pregnant women on the consumption of Fe tablets in the Bebesen Health Center Work Area.
 Methods: Experimental research with participatory action research design (PAR). A sample of 44 pregnant women who were in the Bebesen Health Center area with a gestational age of more than 20 weeks or less than 20 weeks but was the first visit and had made a health visit to a health service place in the working area of the Health Center. Data analysis was carried out with SPSS. Version 25, in the form of univariate and bivariate analysis.
 Results: The promotional strategy applied was effective in changing the mother's behavior in consuming Fe tablets, Zcount = 5.781 (Zcount > 1.96), and p-value = 0.000 (p<0.05).
 Conclusion: Provision of effective health promotion strategies on consumption behavior of Fe tablets.

Compressibility analysis as robust in-die compression analysis for describing tableting behaviour

Abstract Objectives Compressibility of materials is determining the tableting behaviour and tablet properties during and after manufacturing. The compressibility constant has not been investigated as an in-die method yet and was therefore compared with the Heckel analysis for describing the compressibility of materials during tableting in the present study. Methods Various parameters influencing tableting, such as compression pressure, compression speed and punch diameter, were used to analyse the robustness of both methods and to evaluate the informative value of the compression parameters. Twelve common pharmaceutical excipients were used to cover a wide range of material properties. Key findings The compressibility constant was successfully applied as an in-die method and proved to be more robust against the influencing parameters during tableting than the Heckel analysis. A good correlation between the out-of-die and in-die method was found for both methods but could not be observed between the compressibility constant and the yield pressure from Heckel analysis. The methods are both describing the volume reduction of materials under pressure but focus on different material properties. Conclusions For material characterisation in the field of tableting, the compressibility constant can be additionally applied in the future to be able to determine another compressibility parameter in combination with the yield pressure.

Evaluating the effect of kosmotropic inorganic salts in the in vitro dissolution behavior of tablets containing amorphous indomethacin-polyvinylpyrrolidone solid dispersions

The present study evaluates the effect of kosmotropic inorganic salts in the disintegration time and the in vitro dissolution behavior of tablets containing polyvinylpyrrolidone (PVP)-based amorphous solid dispersions (ASDs). Specifically, the impact of KH2PO4, KHCO3 and KCl -which have presented kosmotropic effect on hydrophilic polymers at previous studies- on the performance of tablets containing indomethacin (IND)-PVP ASDs was evaluated. Results showed that all the tested potassium salts presented a kosmotropic effect on PVP, while KH2PO4 was identified as the salt with the greatest impact on PVP's cloud point temperature. Contrary to previously published reports, the in vitro dissolution study of the prepared formulations (with and without inorganic salts) revealed that only the addition of KH2PO4 resulted to increased drug in vitro supersaturation rate and extent. As far as the KHCO3 and KCl are concerned, their incorporation into the systems brought about only a marginal increase in the final level of the API's supersaturation. Interestingly, according to the obtained results, as the inorganic salts' concentration increased, the final supersaturation level of IND decreased in all examined cases. Furthermore, in order to evaluate the moisture-effect on the tablets' performance, pharmaco-technical characterization and in vitro dissolution studies of tablets stored at 60% RH/25 °C took place. Results revealed that the presence of the potassium inorganic salts could not control the moisture's impact on the dissolution profiles and the disintegration time of tablets, highlighting that, in contrary to previous findings, the utilization of kosmotropes salts is not to be considered as a universal solution for the improvement of ASD-based tablet's dissolution/supersaturation performance.

In-Line Green Potentiometric Monitoring of Dissolution Behavior of Losartan Potassium Versus Pharmacopeial Methods: A Comparative Study

Green electro-analytical method was developed and validated for quantitative determination and monitoring of the dissolution behavior of Losartan potassium tablets by in-line potentiometric measurement system with no need for pre-treatment or derivatization of the sample. A sensor was fabricated for in-line determination of Losartan potassium LOS in its dissolution medium utilizing polyvinyl chloride (PVC) based membrane and nitrophenyl octyl ether (NPOE) as a plasticizer. Tetraheptyl ammonium bromide (THAB) was employed as anion exchanger for the first sensor, while cetyltrimethylammonium bromide (CTAB) was used in the second sensor. The proposed method showed fast, stable near Nernstian responses across a relatively wide LOS concentration range (1.0 × 10−5 to 1.0 × 10−2 mol/L) in the case of THAB-based sensor while LOS concentration range was (1.0 x 10−4 - 1.0 × 10−2 mol/L) in case of CTAB-based sensor. The dissolution method was developed according to FDA regulations using USP apparatus II, 50 rpm rotation speed, at 37.0 ± 0.5°C and 900 mL of deareated double distilled water as the dissolution medium. Dissolution profile was generated over 45 min and compared to those obtained by the official spectrophotometric and HPLC methods. The developed method can be efficiently applied as benchtop real-time in-process analysis of LOS concentration. Greenness assessment using Analytical Eco-scale, National Environmental Method Index (NEMI), Green Analytical Procedure Index (GAPI) and Analytical Greenness (AGREE) calculator was conducted to evaluate and compare the proposed method with the official ones.

Fabrication of three-dimensional-printed ofloxacin gastric floating sustained-release tablets with different structures

The objective of this study was to develop a novel ofloxacin gastric floating system with different internal structures by paste extrusion printing and to explore the relationship between tablets with different structures and the release behavior and floating time. The gastric floating sustained release tablets consisted of conventional sustained release pharmaceutical excipients without the addition of foaming agent or light materials. First, the proper alcohol/water proportion was determined for the binding agent. The desired drug release behavior was obtained through modification of the composition of the formulation. In vitro, printed tablets with different structures were evaluated based on drug release, lag time, and floating duration time. Analysis of the floating state data revealed that different internal structures have a significant effect on the floating time. Analysis of the dissolution data of these tablets reveals that the release behavior and release mechanism of tablets with different structures are very similar. DSC, XRD and FTIR data reveal that the drug still exists in crystalline form and that no obvious interaction occurs between the drug and excipients. All these results showed that 3D printing offers unique advantages for the generation of gastric floating preparations, and this method can adjust the floating time without altering the release behavior.

Prediction of quality attributes (mechanical strength, disintegration behavior and drug release) of tablets on the basis of characteristics of granules prepared by high shear wet granulation.

High shear wet granulation is commonly applied technique for commercial manufacturing of tablets. Granulation process for tablets manufacturing is generally optimized by hit and trial which involves preparation of granules under different processing parameters, compression of granules and evaluation of the resultant tablets; and adjustment is made in granulation process on the basis of characteristics of tablets. Objective of the study was to optimize the process of high shear wet granulation and prediction of characteristics of tablets on the basis of properties of granules. Atenolol granules were prepared by high shear wet granulation method, using aqueous solution of polyvinyl pyrrolidone (PVP k-30) as binder. Concentration of binder solution and granulation time were taken as process variables, both studied at three levels. Different combinations of process variables were determined by Design Expert software. Granules were evaluated for different parameters on the basis of SeDeM-ODT (Sediment Delivery Model-Oro Dispersible Tablets) expert system. Granules from all the trials were compressed using round (10.5 mm) flat faced punches at compression weight of 250 mg/tablet. Tablets were evaluated of different quality control parameters as per USP. Results showed that both the process variables had positive effect on mechanical strength of tablets and negative effect on disintegration and dissolution rate. Granule prepared with highest level of binder concentration (15%) and highest granulation time (60 sec) resulted in tablets with highest crushing strength (11.8 kg), specific crushing strength (0.328 kg/mm2), tensile strength (0.208 kg/mm2), lowest value of friability (0.19%) and highest disintegration time (10.9 min), as predicted from granules characteristics on the basis of SeDeM-ODT expert system. Drug release from Trial-13 (processed under highest level of both process parameters) was also lower than rest of the trials. It is concluded from the study that quality characteristics of tablets can be predicted from granules characteristics using SeDeM-ODT expert system. Furthermore, SeDeM-ODT expert system can also be used for optimization of the process of high shear wet granulation.

Tablet formulation development focusing on the functional behaviour of water uptake and swelling

The functional behaviour of tablets is strongly influenced by their manufacturing process and the choice of excipients. Water uptake and swelling are prerequisites for tablet disintegration, dispersion and hence active pharmaceutical ingredient (API) dissolution. High proportions of polymeric excipients in tablets, which are typically used as API carriers in amorphous solid dispersions (ASDs), may be challenging due to the formation of a gelling polymer network (GPN). In this study, systematic investigations into the formulation development of tablets containing polymeric and other excipients are performed by water uptake and swelling analysis. The impact of tablet composition and porosity as well as pH of the test medium are investigated. The pH affects the analysis results for Eudragit L100–55 and Eudragit EPO. HPMC and Kollidon VA64 inhibit water uptake and swelling of tablets due to the formation of a GPN. High tablet porosity, coarse particle size of the polymer and the addition of fillers and disintegrants can reduce the negative impact of a GPN on tablet performance. The application of lubricants slows down the analysed processes. Water uptake and swelling data are fitted to an empirical model obtaining four characteristic parameters to facilitate the simple quantitative assessment of varying tablet formulations and structural properties.

Exploring the unexpected behavior of HPMC matrix tablets in dissolution media with SDS

In the case of poorly soluble drugs, a surfactant is often added to dissolution media to increase drug release. In this study, diclofenac sodium (DF-Na) release from hydroxypropyl methylcellulose (HPMC) matrix tablets was explored in dissolution media containing different sodium lauryl sulfate (SDS) concentrations. Drug release increased with increasing SDS concentration; however, an unexpected decrease in DF-Na release was noticed in the medium with pH 4 containing 0.03–0.08% SDS, which is just below the critical micelle concentration (CMC). In addition, an inverse correlation between swelling and release was noticed. Measurements of transmittance of multiple HPMC–SDS dispersions showed that with increasing HPMC concentration transmittances are lower at a wider SDS concentration interval. Thus, when using media with low SDS concentrations, especially those with concentrations lower than CMC (0.03–0.08%), DF-Na release from HPMC matrix tablets is decreased due to increased swelling and lack of SDS in the swelled layer, both possibly due to SDS binding to HPMC. However, when using media with a higher initial SDS concentration in the medium, there remains a high concentration of non-bound SDS in the bulk, which can solubilize incorporated drug and thus enhance its release from HPMC matrix tablets.

Development of Capsule containing Immediate Release Tablet and Extended Release Floating Tablet for Monitoring Release of Atenolol

Atenolol is beta blocker absorbed through GIT use for heart diseases. Single tablets, floating tablets and sustained released formulations studied are insufficient to produce effective dose to enhance bioavailability and effectiveness. Our study is focused on development of capsule dosage form containing immediate release (IR) and floating extended release (ER) tablets for monitoring release of atenolol in single dosage form. Two different tablets for IR and ER were prepared in three different combinations (Batch). Pre-formulation and post formulation parameters found to be within acceptable limits of formulation. Release behavior of individual tablets and capsule containing two tablets were studied. Among the batches, capsules containing smaller amount of atenolol in IR and large amount of Atenolol in ER (batch II) showed impressive drug release pattern. This formulation was stable even after a month and achieved optimum release behavior of immediate release and sustained release. This study could be used for effective treatment for different heart complications and reduce toxicity due to high plasma concentration in increased dose frequency.