Roxithromycin-loaded lipid nanoparticles for follicular targeting

Area of Science:

• Pharmaceutical Sciences
• Nanotechnology
• Dermatology

Background:

• Particulate drug carriers, such as nanoparticles (NPs), can accumulate in skin hair follicles, increasing local drug concentrations.
• Developing effective follicle-targeting drug delivery systems is crucial for localized therapies.

Purpose of the Study:

• To develop and characterize solid lipid nanoparticles (SLN) loaded with roxithromycin (ROX) for enhanced hair follicle targeting.
• To evaluate the stability, in vitro release, skin irritation, and skin penetration of ROX-loaded SLN.

Main Methods:

• Characterization of SLN including particle size, polydispersity index, zeta potential, and incorporation efficiency.
• In vitro drug release studies and skin irritation tests using EpiDerm™.
• Ex vivo skin penetration studies using fluorescently labeled SLN and in vivo follicular biopsies to analyze drug content.

Main Results:

• ROX-loaded SLN exhibited a mean particle size of 172±2 nm and high incorporation efficiency (82.1±3.0%).
• SLN suspensions showed good long-term stability (up to 26 weeks) and no skin irritation potential.
• Ex vivo and in vivo studies confirmed SLN penetration deep into hair follicles (over 1mm depth), demonstrating successful delivery of ROX to pilosebaceous units.

Conclusions:

• Solid lipid nanoparticles below 200 nm are effective carriers for roxithromycin targeting hair follicles.
• SLN demonstrate potential for localized drug delivery to pilosebaceous units, enhancing therapeutic efficacy and reducing systemic exposure.