A preservative-and-fluorescein interaction model for benign multipurpose solution-associated transient corneal...

Area of Science:

• Ophthalmology
• Materials Science
• Toxicology

Background:

• Transient corneal hyperfluorescence from multipurpose contact lens solutions (MPS) is often linked to corneal injury.
• Understanding the molecular interactions of MPS disinfectants with the corneal epithelium is crucial for assessing biocompatibility.

Purpose of the Study:

• To investigate the molecular interactions between common MPS disinfectants (PHMB, PQ-1) and the corneal epithelium using an in vitro model.
• To determine if these interactions explain preservative-associated transient corneal hyperfluorescence.

Main Methods:

• A liposome-based model simulating the corneal epithelial surface was developed.
• Interactions of polyhexamethylene biguanide (PHMB), polyquaternium-1 (PQ-1), and fluorescein with liposomes were assessed.
• Liposome integrity and membrane interactions were measured using fluorescence anisotropy and melting point temperature.

Main Results:

• PHMB and PQ-1 associated with liposomes, but only PHMB induced fluorescein association with membrane components.
• PHMB did not significantly alter liposome integrity, even at high concentrations.
• PQ-1 disrupted liposomes at concentrations above 7 ppm.

Conclusions:

• PHMB exhibits nondestructive interaction with the corneal epithelial model, even at elevated concentrations.
• PQ-1 causes liposome disruption, indicating potential for corneal cell damage.
• Preservative-associated transient corneal hyperfluorescence may be a benign phenomenon, and its clinical evaluation for cell integrity could be ambiguous.