pH-sensitive microparticles prepared by an oil/water emulsification method using n-butanol

Area of Science:

• Pharmaceutical Technology
• Drug Delivery Systems
• Materials Science

Background:

• Traditional oil/oil emulsification limits lipophilic drug encapsulation in pH-sensitive matrices due to drug loss.
• Developing efficient microencapsulation techniques is crucial for improving drug efficacy and patient compliance.

Purpose of the Study:

• To develop and optimize a novel oil/water emulsification method for microencapsulating lipophilic drugs in pH-sensitive polymers.
• To evaluate the impact of preparation parameters on drug entrapment and release characteristics.
• To investigate the potential of n-butanol as a solvent in this microencapsulation process.

Main Methods:

• Microencapsulation of ibuprofen (lipophilic drug) in Eudragit S100 microspheres using an oil/water emulsification solvent extraction method with n-butanol.
• Optimization of preparation parameters including theoretical drug load and surfactant concentration.
• Morphological analysis of microspheres.
• In vitro drug release studies at different pH values (2.0, 5.5, and 7.4).

Main Results:

• Spherical microspheres with a sponge-like internal structure were successfully prepared.
• Optimized parameters, including drug load and surfactant concentration, significantly influenced drug entrapment efficacy.
• Drug leakage was minimal at pH 2.0, with significant release observed at pH 5.5 and near-immediate release at pH 7.4.
• Particle size remained consistent around 170 micrometers despite process modifications.

Conclusions:

• The proposed oil/water emulsification method using n-butanol is a promising alternative for preparing pH-sensitive microspheres with improved lipophilic drug encapsulation.
• The developed microspheres exhibit significant pH-dependent drug release, suitable for targeted drug delivery applications.
• Further research into n-butanol's role could lead to advanced pharmaceutical formulations.