Smartphone control could mean the end of daily injections for diabetics
The smart technology tells implanted genetically engineered cells when to produce insulin.
In mice experiments the app successfully commanded cells to produce insulin - keeping glucose levels within normal limits for diabetic mice.
More than 415 million people worldwide are living with diabetes and frequently need to inject themselves with the hormone to manage their blood sugars.
The researchers combined living tissues and technology to produce customised cells that produced insulin when illuminated by far-red light - the same wavelengths emitted by infra-red saunas.
They added the cells to a soft bio-compatible sheath that also contained wirelessly-powered red LED lights.
This created watery gels called HydrogeLEDs that could be turned on and off by an external electromagnetic field.
Implanting them into the skin of diabetic mice allowed the researchers to administer insulin doses remotely through the smartphone app.
Dr Jiawei Shao, of East China Normal University in Shanghai, said: "Human cells can be genetically engineered to efficiently manufacture and deliver insulin.
"But most synthetic biological circuits don't offer the same degree of sensitivity and precision as digital sensors."
Human cells are genetically engineered to produce, store and release insulin in response to blood sugar levels in the body.
In tpe 1 diabetes, the immune system destroys the pancreatic cells responsible for making insulin, a hormone crucial to converting blood sugar into energy.
The team custom-coded the smartphone control algorithms and designed the engineered cells to produce insulin without any 'cross-talk' between normal cellular signalling processes.
The scientists went on to pair the system with a Bluetooth-enabled blood glucose metre, creating instant feedback between the therapeutic cells and the diagnostic device.
This helped diabetic animals rapidly achieve and maintain stable blood glucose levels over a period of several weeks, reports Science Translational Sedicine.
The researchers said successfully linking digital signals with engineered cells represents an important step toward translating similar cell-based therapies into the clinic.
This could lead to releasing diabetics from the need to inject insulin daily, and more importantly, protecting them from the debilitating complications of the disease, such as blindness, kidney failure and cardiovascular problems.
Dr Shao said: "With the increasingly dominant role of smartphones in our lives, mobile health care systems integrating advanced point-of-care technologies to manage chronic diseases are gaining attention.
"Using a multidisciplinary design principle coupling electrical engineering, software development, and synthetic biology, we have engineered a technological infrastructure enabling the smartphone-assisted semi-automatic treatment of diabetes in mice."
The World Health Organisation attributed more than 1.5 million deaths to diabetes in 2012.
The development has the potential to impact millions of lives.
Patients would no longer have to manage the condition themselves with daily injections that can be invasive.
Dr Shao said: "Life in the 21st century has become increasingly smartphone-dependent, with most users in modern civilizations storing large amounts of important personal information on their phone, including bank accounts, health data, and instant Global Position System (GPS) locations.
"The use of smartphones for mobile health (mHealth) - defined as the practice of medicine supported by portable diagnostic devices to allow easy and accurate characterisation of health and diseases - is shifting health care models toward increasingly patient-centric designs."
Unlike Type 2, Type 1 diabetes has nothing to do with lifestyle or weight.
The condition can develop at any age, but is usually diagnosed before the age of 40, most commonly in late childhood.
Around 10 per cent of the 3.5 million people diagnosed with diabetes in the UK have Type 1.
Professor Mark Gomelsky, of Wyoming University, who reviewed the study for the journal, said: "An iconic image of medicine that has persisted for many decades involves a doctor equipped with a stethoscope and a bottle of pills, diagnosing diseases and dispensing the drugs to treat them.
"This image is set to change with the emergence of cell-based therapies.
"How soon should we expect to see people on the street wearing fashionable LED wristbands that irradiate implanted cells engineered to produce genetically encoded drugs under the control of a smartphone?
"Not just yet, but the work of Shao et al. provides us with an exciting glimpse into the future of smart cell-based therapeutics."