Diabetes control by smartphone
Cells controlled remotely by a smartphone app can release insulin into the bloodstream to regulate glucose levels in diabetic mice, a new study has shown.
The system, developed by East China Normal University, Shanghai, scientist Haifeng Ye and his colleagues, is centred on a clutch of bio-engineered light-sensitive insulin-secreting cells embedded within a hydrogel gel matrix. This protects them from attack by the recipient's immune system while still allowing nutrients and oxygen to get in and permitting the insulin they produce to move out.
The cells are equipped with a system called "optogenetics" making them sensitive to red light produced by an adjacent LED source - dubbed a hydrogeLED - that's implanted alongside them. When this light is switched on, by beaming in energy magnetically from outside the animal's body, the cells release insulin, bringing down blood sugar.
To make the system work, a small drop of blood was tested regularly with a glucometer similar to the one a diabetic would use before a meal. This beamed the glucose level to a smartphone over a Bluetooth connection. After analysis of the result, the phone triggered the magnetic signal, switching on the LED source inside the mice to produce the right amount of insulin to correct the glucose level.
The technique was able to bring down blood glucose at a steady rate within about 2 hours and then maintain near-normal sugar levels for 15 days, which was the maximum duration of the experiment.
A more autonomous version of the system was also tested that did not require any active intervention via the phone app but nonetheless permitted human external monitoring and over-ride of the device behaviour were this appropriate. The team also envisage a version that will incorporate a battery, avoiding the need to use a magnetic field to power the implanted LEDs.
Their concept, published this week in Science Translational Medicine, "could pave the way for a new era of personalised, digitalised and globalised precision medicine."