Development of modified release diltiazem HCl tablets using composite index to identify optimal formulation

Area of Science:

• Pharmaceutical Technology
• Materials Science

Background:

• Developing modified-release drug delivery systems is crucial for improving therapeutic efficacy.
• Ispaghula husk and guar gum are natural polymers with potential for drug formulation.
• Diltiazem hydrochloride (HCl) is a widely used cardiovascular drug requiring controlled release.

Purpose of the Study:

• To prepare modified-release diltiazem HCl tablets using tartaric acid-treated ispaghula husk.
• To optimize tablet properties and drug release profiles using a 3^2 full factorial design.
• To evaluate the swelling, gelling, and dissolution characteristics of the modified husk.

Main Methods:

• Preparation of tartaric acid-treated ispaghula husk powder.
• Direct compression technique for tablet manufacturing.
• Application of a 3^2 full factorial design to optimize formulation variables.
• Evaluation of tablet crushing strength, swelling, gelling, and drug release.
• Analysis of dissolution profiles in distilled water and simulated gastric fluid (pH 1.2) using similarity factor (f2).

Main Results:

• Modified ispaghula husk exhibited enhanced swelling and gelling properties compared to untreated powder.
• Dicalcium phosphate addition was essential for achieving adequate tablet crushing strength.
• The formulation successfully modulated diltiazem HCl release and demonstrated similar dissolution profiles in different media.
• A composite index was utilized to select the optimal tablet batch based on drug release at various time points.

Conclusions:

• Tartaric acid treatment effectively modifies ispaghula husk for controlled drug release applications.
• Direct compression combined with factorial design is a viable approach for developing modified-release diltiazem HCl tablets.
• The developed formulation shows promise for improved diltiazem HCl therapy through controlled drug delivery.