An artificial pancreas that can help control the havoc-wreaking diabetes causing hormones has been developed and successfully tested.

The system was developed at Boston University (BU), and consists of a blood glucose monitor and insulin pump hooked up to a laptop that runs a programme to control the levels of the important hormones insulin and glucagon. Administering insulin to a type 1 diabetes patient always carries a risk of hypoglycaemia with it. But by running an algorithm that monitors blood sugar levels and is capable of administering both blood-sugar raising and lowering hormones - glucagon and insulin respectively - this system seems to remove that risk.

Edward Damiano, from the BU department of biomedical engineering, who co-led the research team and whose son developed type-1 diabetes aged 1, explains why both hormones are important. "Large doses of glucagon are used as a rescue drug for people with severely low blood sugar,"he says. "Our system is designed to counteract moderate drops in blood sugar with minute doses of glucagon spread out throughout the day, just as the body does in people without diabetes."

The artificial pancreas was first tested in pigs in 2007, and has now being used in 11 type 1 diabetes patients for 24 hours, all given high carbohydrate meals. In six of the eleven the system controlled blood sugar successfully, while five of the patients needed a shot of orange juice to bring their blood sugar levels back to normal.

This mismatch in the first trial was adjusted by tinkering with the algorithms used in the software that control the release of the hormones and the second run was a success in all patients.