We’re always told to read the fine print. That may be even more of a challenge as the writing size gets down to the sub-100-nm scale. A team led by Horacio D. Espinosa at Northwestern University in Evanston, Ill., has created a nanoscale chip that operates like a fountain pen for use with chemical and biomolecular inks.

The Nanofountain Probe, mounted on an atomic force microscope, uses capillary feeding from a built-in reservoir to create a continuous ink flow. The researchers report writing features as small as 40 nm wide.

The technology, made through standard microfabrication techniques, should provide a practical way to create parallel arrays of probes for high-throughput patterning with multiple inks. This could lead to applications in biotechnology, pharmaceuticals and nano-sensors.

It also could put quite a strain on our bifocals.