Image of Printed Electronics
Two electronically active leads directly printed along the underside of Duke graduate student Nick Williams’s pinky successfully light up an LED when a voltage is applied. (Credit: Duke University)

A fully print-in-place technique for electronics that is gentle enough to work on delicate surfaces, including human skin. The advance could enable technologies such as high-adhesion, bandages tricked out with patient-specific biosensors.

The thin film sticks to skin much like a temporary tattoo, and early versions of the flexible electronics were made to contain heart and brain activity monitors and muscle stimulators. While these types of devices are on their way to commercialization and large-scale manufacturing, there are some arenas in which they’re not well suited, such as when direct modification of a surface by adding custom electronics is needed.

Despite the need for each layer to dry completely to avoid mixing materials, the print-in-place techniques can be completed at the lowest overall processing temperature reported to date. While the method won’t likely replace large-scale manufacturing processes for wearable electronics, it has potential value for applications such as rapid prototyping or situations where one size doesn’t fit all.