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Effect of Artificial Tear Formulations on the Metabolic Activity of Human Corneal Epithelial Cells after Exposure to Desiccation
Published on: May 2, 2020
Differential tissue-on-tissue lubrication by ophthalmic formulations
Anne E Meyer1, Robert E Baier, Huagang Chen
1Industry/University Center for Biosurfaces, University at Buffalo, Buffalo, New York 14214-3007, USA.
Summary
A novel formulation with polyethylene glycol, propylene glycol, and hydroxypropyl guar significantly reduced friction between simulated ocular tissues. This advanced lubrication offers improved performance over saline or oil-emulsion preparations for ocular surface health.
Area of Science:
- Biomaterials Science
- Ophthalmology
- Tribology
Background:
- Ocular surface lubrication is crucial for comfort and health, with existing solutions like saline or oil emulsions having limitations.
- Understanding tissue-on-tissue friction is essential for developing effective ocular lubricants.
- Simulating eyelid friction accurately is key to evaluating lubricant performance.
Purpose of the Study:
- To evaluate hydrophilic polymer-containing formulations for ocular surface lubrication.
- To compare the efficacy of a novel formulation against saline and oil-emulsion preparations.
- To assess the friction-reducing properties and substantivity of tested formulations on ocular tissues.
Main Methods:
- Tissue-on-tissue friction testing using preserved human umbilical cord vein segments.
- Reciprocating pin-on-disc tribometer simulating eye-blinking under increasing loads.
- Analysis of friction coefficients and microscopic examination (SEM, light microscopy) post-testing.
Main Results:
- The formulation containing polyethylene glycol (PEG 400), propylene glycol (PG), and hydroxypropyl guar (HP-Guar) demonstrated superior lubrication.
- This HP-Guar formulation achieved a persistent coefficient of friction around 0.05, significantly lower than saline or oil emulsions.
- All tested formulations performed better on tissue-on-tissue interfaces compared to tissue-on-metal oxide or metal oxide-on-metal oxide interfaces.
Conclusions:
- Hydrophilic polymer formulations, particularly the HP-Guar-based one, offer enhanced lubrication for ocular surfaces.
- The study highlights the importance of appropriate tissue-on-tissue simulation for clinically relevant lubrication data.
- The tested formulation shows potential for improving ocular surface comfort and health by reducing friction.
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