Effect of adding non-volatile oil as a core material for the floating microspheres prepared by emulsion solvent...

Area of Science:

• Pharmaceutical Sciences
• Materials Science

Background:

• Prolonging gastrointestinal transit time is crucial for drug efficacy.
• Eudragit microspheres offer potential for controlled drug delivery.
• Buoyancy enhancement is key for sustained gastrointestinal residence.

Purpose of the Study:

• To prepare Eudragit microspheres with enhanced buoyancy for prolonged gastrointestinal transit.
• To investigate the effect of non-volatile oils on microsphere properties and drug release.
• To optimize solvent ratios for desired microsphere morphology and performance.

Main Methods:

• Preparation of Eudragit microspheres using a solvent evaporation technique.
• Incorporation of various non-volatile oils into the dispersed phase.
• Evaluation of microsphere buoyancy, floating time, and drug entrapment efficiency.
• Analysis of microsphere morphology and drug release kinetics.
• Optimization of solvent (dichloromethane:ethanol:isopropanol) ratios.

Main Results:

• Microspheres with water-immiscible non-volatile oils exhibited >90% entrapment and prolonged floating times.
• Optimal microsphere morphology and performance were achieved with a dichloromethane:ethanol:isopropanol ratio of 5:6:4.
• Increased isopropanol content delayed microsphere formation and reduced fibrous substance production.
• Drug release was generally faster from oil-containing microspheres, except for mineral oil formulations.
• Drug solubility in the non-volatile oil significantly influenced release profiles and decreased the glass transition temperature.

Conclusions:

• Non-volatile oils effectively enhance the buoyancy of Eudragit microspheres, prolonging gastrointestinal transit.
• The choice of oil and solvent composition critically impacts microsphere characteristics and drug release.
• Optimized Eudragit microspheres with entrapped oils represent a promising approach for sustained drug delivery.