Posted: September 19, 2007

Printing with enzymes instead of ink

(Nanowerk News) With all the advances in printing technology in recent years, the latest may rise to the top of a list that would make Gutenberg gasp. Scientists in North Carolina are reporting development and testing of a method for printing finely-detailed microscopic images with an enzyme, rather than ink. The report is scheduled for the Sept. 24 issue of ACS' Journal of Organic Chemistry, a bi-weekly publication ("Biocatalytic Microcontact Printing"").  
In the study, Eric J. Toone and Robert L. Clark and colleagues point out that so-called microcontact printing has found wide application for rapidly transferring high-resolution images onto large surfaces. But current nanoprinting technology relies on the diffusion of ink, and cannot reproduce details smaller than one hundred nanometers in diameter—about 400 times smaller than the width of a human hair.  
The new technology, termed biocatalytic microcontact printing, involves coating a nano-"stamp" with an enzyme — a protein that speeds up chemical reactions. The enzyme then digests away a layer on the surface, leaving behind an imprint almost like an old-fashioned rubber stamp. Becauseno diffusion of ink is involved in the process, the resolution of microcontact printed images is about one hundredfold greater than possible with conventional technology. The technique may point the way toward faster, less expensive methods of nanolithography, which could be used to create complex structures for micromachines, biosensors, and other nanoscale devices, the researchers suggest.
Source: American Chemical Society