Formulation and Evaluation of Clarithromycin Loaded Nanostructured Lipid Carriers for the Treatment of Acne

Background: Clarithromycin is a macrolide antibiotic used in acne treatment, but it has poor solubility, which decreases its permeability through lipid barriers such as skin. Nanostructured lipid carriers can enhance the permeability of clarithromycin through the skin, thus improving its potential for controlling acne.

Aim: To formulate and evaluate Nanostructured lipid carriers of clarithromycin for topical delivery in acne treatment

Methods: Nanostructured lipid carriers were prepared by emulsification and ultrasonication methods using lipids such as glycerol monostearate and oleic with poloxamer 188 as stabilizer. These nano-carriers were optimized with the help of the Quality by Design (QbD) approach employing Design-Expert® software. The nanoparticles were characterized for particle size analysis, zeta potential, drug-excipient compatibility, entrapment efficiency, and surface morphology by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). The nano-carriers were also investigated for in vitro drug release and ex vivo permeation through excised goat skin. The optimized formulation was incorporated into topical carbopol gel base, formulated and examined for pH, viscosity, spreadability, in vitro drug release, ex vivo permeation, and stability under accelerated conditions.

Results: The average particle size of the optimized nanoparticles was 164.8 nm, and zeta potential was -39.2 mV. FTIR studies showed that drug and lipids are compatible with each other. The morphology study by SEM and TEM showed spherical shaped particles. The entrapment efficiency of the optimized formulation was found to be 88.16%. In vitro drug release studies indicated sustained release from the formulation due to diffusion through the lipid matrix of the particles. The ex vivo permeation study using goat skin produced greater permeation from the NLC gel (89.5%) than marketed gel (65%) due to the lipid solubility of the nanoparticles in the skin. The formulation was stable under accelerated conditions.

Conclusion: The optimized formulation can be considered as promising nano-carriers suitable for the sustained release of clarithromycin into the skin for effective control of acne.