Temporary tattoo monitors blood-sugar levels
Nanoengineers who tested the device say it will also one day have bluetooth capabilities to send information to GPs.
A temporary tattoo may offer patients with diabetes a non-invasive method of monitoring their blood-sugar levels. Nanoengineers who tested the device say it will also one day have bluetooth capabilities to send information to GPs.
According to the research, which has been published in Analytical Chemistry, the tattoo can extract and measure the level of glucose in the fluid between skin cells.
Diabetes affects hundreds of millions of people worldwide and is one of the top causes of death and disability. Often, patients must test their glucose levels several times every day, using a tiny needle to extract blood from the fingertip.
Researchers say they wanted to find a less invasive method, as patients who find it too difficult or unpleasant to extract blood face higher risk of poor health.
The tattoo was developed and tested by graduate student Amay Bandodkar and colleagues in Professor Joseph Wang's laboratory at UC San Diego in California.
It was applied to seven men and women aged 20-40 with no history of diabetes. Volunteers taking part in the study consumed a carbohydrate-rich sandwich and soda to see how well the sensor picked up the hike in glucose levels after a meal. Researchers found the tattoo to be as effective as the traditional method of testing glucose levels.
The device is formed of carefully patterned electrodes printed on temporary tattoo paper. A very mild electric current is applied to the skin for 10 minutes, forcing sodium ions in the fluid between skin cells to migrate towards the electrodes.
A sensor in the tattoo determines the person's glucose levels by measuring the strength of the electrical charge produced by the glucose found in the sodium ions and fluid.
According to the research findings, the tattoo can survive for a day and costs just a few cents. The team are now working on making it last longer while keeping the cost down.
Bandodkar said the team "envisions using these glucose tattoo sensors to continuously monitor large populations as a function of their dietary habits."
The sensor may also have many other applications, researchers say, such as delivering medicines through the skin, testing how well a medication is working, detecting alcohol or illegal drug consumption and monitoring fitness in athletes.
Currently, the tattoo does not provide a numerical reading that would be needed for patients to monitor their own blood-sugar. This is now being developed by electrical and computer engineering researchers at the Centre for Wearable Sensors at UC San Diego.
Image courtesy of UC San Diego
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