Microbiocidal characterization of a novel povidone-iodine based rigid contact lens disinfecting solution

Area of Science:

• Ophthalmology and Vision Science
• Microbiology
• Materials Science

Background:

• Rigid gas permeable (RGP) contact lenses require effective disinfection solutions to prevent microbial keratitis.
• Existing multipurpose and hydrogen peroxide solutions have varying efficacies and potential drawbacks.
• Novel disinfection agents are needed to enhance RGP lens care and patient safety.

Purpose of the Study:

• To evaluate the antimicrobial efficacy of a new povidone-iodine based disinfection solution for RGP lenses.
• To compare its performance against established multipurpose and hydrogen peroxide solutions.
• To assess the long-term storage stability and safety profile of the povidone-iodine solution.

Main Methods:

• Bactericidal and fungicidal activity assessed per ISO 14729 standards.
• Amoebicidal activity evaluated using an automated viability counter against Acanthamoeba castellani.
• Long-term storage stability tested over a 3-month period.
• All solutions assessed for compliance with FDA guidelines.

Main Results:

• All tested solutions met FDA guidelines for RGP lens disinfection.
• 3-month storage did not compromise the antimicrobial activity against bacteria and fungi.
• The povidone-iodine solution achieved a 1-log reduction in Acanthamoeba trophozoites.
• Reduced viability of Acanthamoeba cysts ranged from 78-86% across solutions.

Conclusions:

• The povidone-iodine based solution offers comparable antimicrobial efficacy to current RGP lens care products.
• It demonstrates good stability and meets regulatory standards for disinfection.
• Potential advantages include lack of demonstrated resistance and reduced toxicity, warranting further investigation.