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Controlled-release carbamazepine matrix granules and tablets comprising lipophilic and hydrophilic components.

Barakat NS, Elbagory IM, Almurshedi AS - Drug Deliv (2009)

Bottom Line: 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.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia. nsybarakat@yahoo.com

ABSTRACT
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 (f(2) 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.

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Related in: MedlinePlus

Water uptake (swelling %) of compacted matrix-forming components.
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fig5: Water uptake (swelling %) of compacted matrix-forming components.

Mentions: Figure 5 summarizes the results obtained from the hydration process of the compacted matrix components (tablets without CBZ). They support the dissolution results (Figure 4). The compacted matrix components of formulae A1, A2, and A3 (with more than one weight ratio of Compritol®/HPMC) exhibited relatively faster water uptake (swelling) during the first 1 hr of immersion followed by a steady hydration rate (water uptake plateau) for the next 6 hr. In contrast, the compacted matrix components of formulae A4 and A5 (with less than one weight ratio of Compritol®/HPMC) showed significant erosion which was becoming faster with the increase in the HPMC content. From the above mentioned we can conclude that the overall CBZ dissolution rate and, ultimately, availability for absorption should be controlled by the rate of matrix swelling, drug diffusion through the gel layer, and erosion of the outer gel layer (Roy and Rohera 2002).


Controlled-release carbamazepine matrix granules and tablets comprising lipophilic and hydrophilic components.

Barakat NS, Elbagory IM, Almurshedi AS - Drug Deliv (2009)

Water uptake (swelling %) of compacted matrix-forming components.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2637677&req=5

fig5: Water uptake (swelling %) of compacted matrix-forming components.
Mentions: Figure 5 summarizes the results obtained from the hydration process of the compacted matrix components (tablets without CBZ). They support the dissolution results (Figure 4). The compacted matrix components of formulae A1, A2, and A3 (with more than one weight ratio of Compritol®/HPMC) exhibited relatively faster water uptake (swelling) during the first 1 hr of immersion followed by a steady hydration rate (water uptake plateau) for the next 6 hr. In contrast, the compacted matrix components of formulae A4 and A5 (with less than one weight ratio of Compritol®/HPMC) showed significant erosion which was becoming faster with the increase in the HPMC content. From the above mentioned we can conclude that the overall CBZ dissolution rate and, ultimately, availability for absorption should be controlled by the rate of matrix swelling, drug diffusion through the gel layer, and erosion of the outer gel layer (Roy and Rohera 2002).

Bottom Line: 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.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.

View Article: PubMed Central - PubMed

Affiliation: Department of Pharmaceutics, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia. nsybarakat@yahoo.com

ABSTRACT
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 (f(2) 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.

Show MeSH
Related in: MedlinePlus