Hydroxyethyl Pachyman as a novel excipient for sustained-release matrix tablets

Area of Science:

• Pharmaceutical Sciences
• Materials Science

Background:

• Sustained-release drug delivery systems are crucial for improving therapeutic efficacy and patient compliance.
• Hydrophilic matrices are widely used to control drug release rates.
• Novel matrix materials are continuously sought to optimize drug delivery performance.

Purpose of the Study:

• To evaluate hydroxyethyl pachyman (HEP) as a novel hydrophilic matrix for sustained-release tablets.
• To investigate the effect of formulation variables and dissolution conditions on diclofenac sodium (DS) release from HEP matrices.

Main Methods:

• Tablets were prepared using diclofenac sodium (DS) as a model drug and hydroxyethyl pachyman (HEP) as the matrix material.
• Formulations were prepared by direct compression and wet granulation methods.
• Drug release studies were conducted in simulated gastric fluid (SGF, pH 1.2) and simulated intestinal fluid (SIF, pH 6.8).
• Tablet morphology was examined using microscopy.

Main Results:

• Tablets prepared by wet granulation exhibited significantly slower DS release compared to direct compression.
• Increased HEP concentration in the formulation led to decreased drug release rates.
• DS release was higher at pH 6.8 (SIF) than at pH 1.2 (SGF).
• Morphological studies revealed gel layer formation around the tablets in dissolution media, indicating a combination of diffusion and matrix erosion mechanisms.

Conclusions:

• Hydroxyethyl pachyman (HEP) demonstrates potential as an effective hydrophilic matrix for developing sustained-release tablets.
• The preparation method (wet granulation vs. direct compression) significantly influences drug release kinetics.
• HEP-based matrices offer tunable drug release profiles, influenced by formulation composition and physiological pH conditions.