Testing Oxygen Permeability in Contact Lenses

For comfortable and healthy contact lens wear, oxygen must reach the cornea. Insufficient oxygen can cause discomfort, dryness, and potentially serious eye problems. This is why oxygen permeability testing is so important. It measures how much oxygen can pass through a contact lens material, ensuring adequate oxygen supply to the eye.

Various methods exist to measure oxygen permeability, each designed to accurately quantify a lens's ability to "breathe." This measurement is expressed as Dk/t, where D (Diffusivity) represents the rate at which oxygen moves through the material, and k (Solubility) indicates how much oxygen can dissolve within the material, t refers to the thickness of the lens. A higher Dk/t value signifies greater oxygen flow to the cornea, minimizing the risk of hypoxia (oxygen deficiency).

ISO 18369 provides a general framework and defines terms related to contact lenses, including oxygen permeability. It specifically outlines the procedures for both polarographic and coulometric methods. ISO 9913 focuses specifically on the coulometric method for measuring oxygen permeability. It provides detailed instructions on the equipment, calibration, and testing procedures.

Labthink C230H Oxygen Transmission Rate Test System is designed and manufactured based on the coulometric sensor method. This instrument can be used to measure the oxygen transmission rate of materials with high and medium barrier properties with high accuracy and high efficiency.

This testing is crucial for both manufacturers and wearers. It allows manufacturers to develop and refine lens materials that prioritize eye health. For wearers, it ensures they choose lenses that provide sufficient oxygen, promoting comfort and reducing the risk of complications.

As the demand for functional materials grows, testing methods are evolving to ensure a more comprehensive evaluation. Labthink encourages collaboration with packaging and materials industries companies for quality control! Visit the website www.labthink.com to learn more!