A Method for Efficient Loading of Ciprofloxacin Hydrochloride in Cationic Solid Lipid Nanoparticles: Formulation and...

Area of Science:

• Nanotechnology
• Pharmaceutical Sciences
• Materials Science

Background:

• Solid lipid nanoparticles (SLN) offer a promising platform for drug delivery.
• Ciprofloxacin (CIP) is a widely used antibiotic requiring effective delivery systems.
• Enhancing antibiotic interaction with bacterial membranes is crucial for improved efficacy.

Purpose of the Study:

• To produce ciprofloxacin-loaded solid lipid nanoparticles (CIP-SLN) using quasi-emulsion solvent diffusion (QESD) and solvent injection (SI) methods.
• To investigate the effect of incorporating a cationic lipid (didecyldimethylammonium bromide, DDAB) on SLN properties and antibacterial activity.
• To evaluate the physical stability and in vitro antimicrobial efficacy of the developed CIP-SLN.

Main Methods:

• Production of SLN via QESD and SI techniques.
• In situ conversion of ciprofloxacin hydrochloride to free base for enhanced entrapment.
• Incorporation of DDAB to create positively charged SLN.
• Particle size analysis, zeta potential measurements, and encapsulation efficiency determination.
• In vitro microbiological assays against various bacterial strains.

Main Results:

• Homogeneous SLN populations (250–350 nm) were obtained with >85% drug encapsulation.
• SLN exhibited physical stability for up to nine months at 4°C and 25°C.
• CIP-SLN with DDAB showed significantly lower Minimum Inhibitory Concentration (MIC) values (2–4 log dilutions) compared to free CIP, indicating enhanced antibacterial activity.
• SLN without DDAB demonstrated MIC values comparable to free CIP.

Conclusions:

• Both QESD and SI are suitable methods for producing stable, high-encapsulation CIP-SLN.
• The addition of DDAB to SLN enhances the antibacterial activity of ciprofloxacin.
• Positively charged SLN represent a potential strategy to improve antibiotic efficacy against bacterial infections.