Methazolamide calcium phosphate nanoparticles in an ocular delivery system

Area of Science:

• Ophthalmology
• Nanotechnology
• Materials Science

Background:

• Glaucoma management requires effective intraocular pressure (IOP) reduction.
• Current treatments have limitations in duration and efficacy.
• Local drug delivery systems are being explored to improve therapeutic outcomes.

Purpose of the Study:

• To develop and evaluate a novel nanoparticle-based system for the local ocular delivery of methazolamide.
• To assess the physicochemical properties, drug release kinetics, and in vivo efficacy of methazolamide-loaded calcium phosphate nanoparticles.

Main Methods:

• Methazolamide-loaded calcium phosphate (CaP) nanoparticles were synthesized via inorganic core formation and drug adsorption.
• Characterization included UV-vis spectrophotometry for drug loading, surface charge, and particle size analysis.
• In vitro drug release studies and in vivo IOP-lowering assessments were performed.
• Stability of the formulation was evaluated under accelerated conditions.

Main Results:

• CaP nanoparticles successfully loaded methazolamide with a maximum loading of 0.2% (w/w).
• Particles exhibited a negative surface charge (-30 mV) and a mean diameter of 256.4 nm.
• In vitro studies showed diffusion-controlled methazolamide release over 4 hours.
• In vivo studies demonstrated an 18-hour IOP-lowering effect, significantly outperforming 1% brinzolamide eye drops (6 hours).
• The formulation remained stable for 6 months at 40°C.

Conclusions:

• Methazolamide-bound CaP nanoparticles represent a promising platform for sustained local ocular drug delivery.
• This novel formulation offers a significantly prolonged IOP-lowering effect, potentially improving glaucoma management.
• The physical stability suggests feasibility for clinical application in treating glaucoma.