« World's Largest Basket | Home | 10 Million Candlepower Portable Spotlight »

April 2, 2005

BehindTheMedspeak: Instrumented Contact Lenses — iSugar?


Just as the cell phone turns out to be the technological equivalent of the proverbial camel's nose under the tent, bringing in all manner of increasingly exotic functions via its small footprint and simple user interface, so does the humble contact lens, previously considered simply a substitute for glasses, look to be the equivalent for the human body.

This past Thursday I touched on the use of contact lenses as drug delivery systems.

Today I bring you news of their potential use as a diagnostic tool.

Chris Geddes of the Center for Fluorescence Spectroscopy at the University of Maryland has created glucose-sensing contact lenses so that diabetics can monitor their blood sugar levels accurately and noninvasively.

Now, we've previously had a look at the GlucoWatch (below), a glucose-measuring watch-like device that also works noninvasively.


However, the GlucoWatch's manufacturer still recommends occasional blood sugar monitoring through finger pricks.

The technology of glucose-sensing contacts is deceptively simple: scientists add boronic acid to disposable contact lenses as they are being manufactured.

Glucose-containing moisture in the tear ducts binds with the molecules of boronic acid, causing a fluorescent glow which is then detected with a hand-held device that flashes a blue light into the eye and measures the intensity of the glow, converting it into a number corresponding to the wearer's blood sugar.

Other sensors to measure sodium, potassium, cholesterol, and theorectically any constituent of body fluids could be placed in contacts.

Geddes' group is also working on a contact lens that changes color under normal lighting conditions to indicate blood sugar levels.

The lens would shift from green to yellow to orange to red, enabling the wearer or an observer to determine a broad range of blood sugar levels, from too low to too high.

That might become a fashion accessory in its own right, apart from its medical uses.

And what about having the lenses react to varying levels of neurotransmitters?

Put in a glowing, color-coded dopamine sensor and you could tell if someone liked you in the dark: no need to see if their pupils were enlarged.


Talk about "turn on your love light."

I see these new uses for contact lenses as just the beginning.

There is no reason why nanotechnology can't be adapted to lenses such that they act as transmitters, receivers and personal viewing screens.

No one would know you're watching "The Three Stooges" during your weekly corporate meeting until you doubled over after Moe told Curly to "pick two — any two" and gave him a good poke.



April 2, 2005 at 02:01 PM | Permalink


TrackBack URL for this entry:

Listed below are links to weblogs that reference BehindTheMedspeak: Instrumented Contact Lenses — iSugar?:


The comments to this entry are closed.