Cleaning solution test doesn’t move contact lens wearers to tears

Researchers in the US have made a device to personalise contact lens care.

In the US, over 30 million people wear contact lenses and each year around 60,000 contract serious eye infections that put them at risk of going blind. Thorough cleaning is vital to prevent bacterial build-up on the lens but research has also shown that an individual’s tear chemistry affects the effectiveness of cleaning solutions.

Currently user’s trial various contact lens materials and cleaning regimes to find the one best suited to them. Now, K Scott Phillips from the US Food and Drug Administration and Zhenyu Li at George Washington University, and their team, have incorporated user’s tears into a microfluidic chip that examines microbial growth on a lens against different cleaning solutions. Only a very small sample (1µl) is required – other tests need around 20µl or even 3ml – so there’s no need for patients to watch Black Beauty to generate enough tears.

The team use the device to demonstrate how tears impacts lens selection and care, and say it could be adapted for point-of-care testing in eye clinics.