Optimizing flurbiprofen-loaded NLC by central composite factorial design for ocular delivery

Area of Science:

• Pharmaceutical Sciences
• Nanotechnology
• Ocular Drug Delivery

Background:

• Topical ocular drug delivery faces challenges like poor bioavailability and rapid clearance.
• Flurbiprofen (FB) is a non-steroidal anti-inflammatory drug used for ocular conditions.
• Lipid nanoparticles offer potential for improved ocular drug delivery.

Purpose of the Study:

• To design and optimize nanostructured lipid carriers (NLC) for topical ocular administration of flurbiprofen (FB).
• To investigate critical formulation variables affecting NLC physicochemical properties.
• To evaluate the in vitro performance and safety of the optimized NLC.

Main Methods:

• Hot high-pressure homogenization technique for NLC preparation.
• Central rotatable composite design for optimization of critical variables (lipid ratio, surfactant, drug concentration).
• Physicochemical characterization (particle size, PDI, zeta potential, EE), morphology, crystallinity, stability, in vitro release, and cytotoxicity studies.

Main Results:

• Optimized NLC formulation achieved an average particle size of 228.3 nm with a narrow size distribution (0.156).
• High encapsulation efficiency (∼90%) and a negative surface charge (-33.3 mV) were obtained.
• Sustained in vitro release of flurbiprofen was demonstrated, with no observed toxicity on ocular tissues.

Conclusions:

• Optimized nanostructured lipid carriers provide a promising platform for sustained ocular delivery of flurbiprofen.
• The developed NLC system is safe for ocular tissues.
• This formulation has potential for enhanced therapeutic efficacy in treating ocular inflammatory conditions.