The management of diabetes is a complex matter. Basically what you need is an artificial pancreas that can flank the failing pancreas in some of its function.
Progresses have been made from the invention of synthetic insulin to make for the missing one produced by the pancreas to the insulin pumps used nowadays.
The complexity is related to the dosage. In our body the pancreas is both a sensor, a producer and a releaser of insulin. This keeps the glucose in the blood constant. That is good for distributing energy to the cells and the constant levels avoid both cell starving and degenerating from an excess of glucose.
With the injection of insulin it is up to the patient to estimate the level of glucose and inject accordingly. In practice diabetic are on a regulated diet and are being advised when and how much insulin to inject. If their diet shift from the mandated one (in time, quantity and quality) the matching is no longer good. Same goes if the demand of glucose by cells/body varies as consequence of, as an example, physical activity and external temperature changes.
It is clearly quite complex to replicate the pancreas. Unfortunately, failure in doing that leads to health problems, sometimes quite severe ones.
It is therefore interesting the news coming from Oregon State University where a team of researchers have developed a technology to print a sensor directly onto a catheter that can be used by the insulin pump (usually attached to the body by a belt) to evaluate the level of glucose and deliver the appropriate amount of insulin at the right time.
To create the sensor the researchers have used an e-jet printer that is in principle similar to the usual ink-jet printer you may have at home. The difference is that the drops of ink being printed are smaller and the ink can consist of bio-molecules, like enzymes.
The printing is made on a prepared layer of very thin plastic, comparing in thickness to the plastic foil we use in our kitchen to wrap food. The substrate is so thin, and the deposition process creating the sensors does not change the thickness at all, that it can easily be wrapped around the catheter that is inserted in the diabetic patient belly to deliver the insulin. The sensor detect the glucose level in the body and the insulin pump reacts accordingly.
Another amazing application of 3D printing!