Controlled poorly soluble drug release from solid self-microemulsifying formulations with high viscosity...

Area of Science:

• Pharmaceutical Technology
• Drug Delivery Systems
• Materials Science

Background:

• Poorly water-soluble drugs present challenges for oral delivery.
• Hydroxypropylmethylcellulose (HPMC) is a common polymer for controlled release formulations.
• Self-microemulsifying systems (SMES) can enhance the solubility and bioavailability of lipophilic drugs.

Purpose of the Study:

• To develop a controlled release system for poorly water-soluble drugs using SMES.
• To investigate the effect of SMES on the particle structure and drug release profile.
• To evaluate the potential of HPMC-based formulations containing SMES for oral drug delivery.

Main Methods:

• Spray drying was used to prepare HPMC-based particle formulations.
• Formulations included nimodipine (a model drug) with HPMC, and HPMC with nimodipine dissolved in SMES.
• Particle characterization involved TEM, SEM, DSC, and X-ray powder diffraction.
• In vitro drug release studies were conducted and analyzed using the power law model.

Main Results:

• Distinct differences in particle structure were observed between formulations with and without SMES.
• Both formulation types exhibited controlled release profiles for nimodipine, characterized by the power law.
• The release parameters (n and K) correlated with HPMC viscosity and were influenced by the presence of SMES.
• In solid SMES formulations, nimodipine-loaded oil droplets diffused from HPMC matrices in aqueous media.

Conclusions:

• Controlled release of poorly soluble drugs can be achieved using HPMC-based solid oral dosage forms containing SMES.
• SMES incorporation influences particle morphology and modulates drug release kinetics.
• This approach offers a viable strategy for enhancing the oral delivery of challenging drug compounds.