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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

% Carbamazepine released from prepared matrix tablets and commercial product Tegretol®.
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fig4: % Carbamazepine released from prepared matrix tablets and commercial product Tegretol®.

Mentions: The release profiles obtained from the matrix-tablets and the Tegretol® tablets are presented in Figure 4. They show that the release rate from the control tablets (with Compritol®:Avicel® at a 9:1 weight ratio) was very slow. Also they show that the increase of HPMC content affects significantly the matrix tablet release behavior. The percentage of CBZ released over 7hr from the formulation of highest HPMC content (formula A5 with Compritol®/HPMC weight ratio 1:8) was 76.8%. In general the faster CBZ release rate with the HPMC increased content could be due to more rapid penetration of water into the matrix and/or more matrix erosion. However, a gradual disintegration of the swollen HPMC-based tablets was observed during the release studies. This may be explained by an axial expansion of the tablets as described by Rajabi-Siahboomi et al. (1994). Close examination of the HPMC containing matrix-tablets showed that the extent of their deformation was greater for those of higher HPMC content.


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

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

% Carbamazepine released from prepared matrix tablets and commercial product Tegretol®.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

fig4: % Carbamazepine released from prepared matrix tablets and commercial product Tegretol®.
Mentions: The release profiles obtained from the matrix-tablets and the Tegretol® tablets are presented in Figure 4. They show that the release rate from the control tablets (with Compritol®:Avicel® at a 9:1 weight ratio) was very slow. Also they show that the increase of HPMC content affects significantly the matrix tablet release behavior. The percentage of CBZ released over 7hr from the formulation of highest HPMC content (formula A5 with Compritol®/HPMC weight ratio 1:8) was 76.8%. In general the faster CBZ release rate with the HPMC increased content could be due to more rapid penetration of water into the matrix and/or more matrix erosion. However, a gradual disintegration of the swollen HPMC-based tablets was observed during the release studies. This may be explained by an axial expansion of the tablets as described by Rajabi-Siahboomi et al. (1994). Close examination of the HPMC containing matrix-tablets showed that the extent of their deformation was greater for those of higher HPMC content.

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