Physical characterization and dissolution properties of ibuprofen: Eudragit coprecipitates

Area of Science:

• Pharmaceutical Sciences
• Materials Science
• Drug Delivery

Background:

• Ibuprofen is a widely used non-steroidal anti-inflammatory drug (NSAID).
• Developing sustained-release formulations can improve patient compliance and therapeutic efficacy.
• Eudragit polymers offer versatile properties for modifying drug release profiles.

Purpose of the Study:

• To prepare and characterize ibuprofen-Eudragit coprecipitates.
• To evaluate the dissolution characteristics and physical properties of these coprecipitates.
• To assess the potential of these coprecipitates for ibuprofen sustained-release tablet formulation.

Main Methods:

• Coprecipitation of ibuprofen with various anionic, zwitterionic, and anionic:cationic Eudragit polymers at a 10:3 ratio.
• Physical characterization using X-ray diffractometry, IR spectrophotometry, and differential scanning calorimetry (DSC).
• Dissolution studies in different pH media and calculation of dissolution rate constants using the Higuchi equation.

Main Results:

• No significant molecular interaction was observed between ibuprofen and most Eudragit polymers, except for Eudragit S100 + E100.
• Dissolution of ibuprofen was retarded from most coprecipitates, particularly in pH 6.8-7.5 media.
• Dissolution rates decreased in the order: anionics > zwitterionics > anionic + cationic mixtures. Improved flow properties were noted, except for Eudragit RLPM and RSPM.

Conclusions:

• Eudragit coprecipitates, prepared via a simple, solvent-minimizing technique, can effectively retard ibuprofen dissolution.
• The swelling and slower dissolution of the polymer matrix are key release mechanisms.
• These coprecipitates show promise for developing ibuprofen sustained-release tablets.