Controlled release matrix tablets with HPMC KLV, HPMC K4M, HPMC K15M, and HPMC KM were formulated by wet (non-aqueous) granulation method. Surface plots of log viscosity with temperature (°C) and HPMC concentration (%, w/w) for HPMC a K LV, b K4M, c K15M and d KM. Download/Embed scientific diagram | Swelling index of HPMC K4M at different concentrations from publication: Influence of different grades and concentrations .

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The n values ranged from 0. Also, the drug has good solubility in the release medium, and hence, the drug present on the surface might have been released quickly because of the presence of the more pores in the matrix structure. The following variations in tablet formulae were done and their effect on in vitro release rate, release mechanism Fickian or non-Fickianand nature of release order of release was studied.

The aim of the present investigation was to develop oral controlled release matrix tablet formulations of isoniazid using hydroxypropyl methylcellulose HPMC as a hydrophilic release retardant polymer and to study the influence of various formulation factors like proportion of the polymer, polymer viscosity grade, compression force, and release media on the in vitro release characteristics of the drug.

Hypromellose INNshort for hydroxypropyl methylcellulose HPMCis a semisyntheticinert, viscoelastic polymer used as eye drops, as well as an excipient and controlled-delivery component in oral medicaments, found in a variety of commercial products.

Hypromellose – Wikipedia

This website provides links to other websites owned by third parties. In the PCA scores plot, four distinct groups of formulations were also observed circled. A simple equation for description of solute release. J Phys Chem Solids. At this stage, the HPMC network would be continuous as the particles might be close enough to be in contact with one another, resulting in a great resistance to the flow of molten PEG.

Ashland makes their documentation available in the regions indicated below: Therefore, it is harder for longer chains l4m dissolve because of the high energy required for pulling them off the matrix.


The release profiles were also analyzed for the similarity factor f 2 values for assessment of statistical difference or similarity between the release profiles. Modeling and comparison of dissolution profiles. A special grade of Methocel VLV, developed for coating purposes, was also included in this study.

The formulations within each group in line plot Fig. Further, it was an important aspect of the present investigation to develop an oral CR matrix tablet of isoniazid which could provide both initial release as a free isoniazid immediate release portion followed by the controlled release as a matrix component from a single formulation.

No particular trend was observed when comparing the scores plot of the ternary and binary formulations. For more detailed comparison, rheological profiles can be analysed within the required temperature range, but it was not the objective of hpc study.

Particle size and size distribution of HPMC played important roles in the viscosity of melt suspensions with smaller particles leading to a greater viscosity than larger particles. For this study, two batches of formulations were selected varying in their viscosity grades HPMC.

The sprayability of the molten mixture was assessed by evaluating its product yield obtained after the spray congealing process. The reason for initial higher release and decrease in the rate of isoniazid with time can be explained as follows.

Line plots of melt suspension viscosities with increasing temperature for a F-series, b E-series and c K-series. However, UL assumes no responsibility or liability for the accuracy of the information contained on this website and strongly encourages that upon final product or material selection information is validated with the manufacturer. Hpmd the corresponding melt upmc, those consisting of E15 LV also had the lowest viscosity. Ashland is a developer and manufacturer of stabilizers and gums used in the Food, Beverage, and Nutrition industry.

Therefore, the use of principal component analysis was explored to compare the viscosity profiles of the various formulations. We’re sorry, but the industry you have selected is not currently available in your chosen language.


This observation reflected the complex interactions affecting viscosity when different components are used in a formulation and reinforces the need of using PCA to evaluate the various formulations.

Because hypromellose solution is a non-newtonian solution and exhibits pseudoplastic, more specifically, thixotropic behavior, various test methods are available, and the results of different methods and viscosmeters do not necessarily correspond to each other.

Cumulative percent of drug released was calculated, and mean of six tablets from three different batches were used in the data analysis. At a slightly larger HPMC size, the particles would be further apart, accounting for the drop in viscosity. Jpmc Hall Professional Technical Reference; Therefore, the control of viscosity of PEG melt suspension is more readily achieved by modifying the amount of solids rather than regulating the temperature of the process.

Four distinct groups of viscosity profiles obtained using the rheometer were observed. The viscosity profiles suggested that the F-series generally had more extensive particle-particle interactions compared hpkc the K-series, followed by the E-series at the same concentration.

The results alluded that E15 LV did not exhibit particle-particle interaction. The release rate from matrix systems remains unaffected by thin spots, pinholes, and other similar defects, which can be a serious problem with reservoir systems 2. The suitability of PCA as an analytical tool was assessed before its application to differentiate the hpmf viscosities of the polymer melt suspensions.

The good correlation between the scores plot generated and viscosity profiles determined using a rheometer established that PCA was able to successfully compare various viscosity profiles and differentiate them into clusters of similar viscosities.

This might probably be due to the hpmmc influence of initial tablet matrix porosity on the initial release of soluble drug isoniazid once the minimum hardness was achieved 7.