Scientists at the University of Toronto (U of T) and Arizona State University (ASU) have developed the first direct gene circuit to electrode interface by combining cell-free Synthetic Biology with state-of-the-art nanostructured electrodes.
Long inspired by concepts from the field of electronics, with its circuits and logic gates, synthetic biologists have sought to reprogram biological systems to carry out artificial functions for medical, environmental, and pharmaceutical applications. This new work moves the field of synthetic biology toward biohybrid systems that can take advantage of benefits from each discipline.
Bringing the capacity to detect the Zika virus outside of the clinic and to the point-of-need was a crucial step forward, but the approach relied on conventional optical signaling -- a change in colour to indicate that the virus had been detected. This posed a challenge for practical implementation in countries like Brazil where viruses with similar symptoms require health care providers to screen for several different pathogens in order to correctly identify the cause of a patient's infection.
This highlighted the need for a portable system that could accommodate many sensors in the same diagnostic test, a capability known as multiplexing. The challenge was that multiplexing with colour-based signaling is not practical.
The new biohybrid systemuses non-optical reporter enzymes contained within 16 microlitres of liquid which pair specifically with micropatterned electrodes hosted on a small chip no more than one inch in length. Within this chip, gene-circuit-based sensors monitor the presence of specific nucleic acid sequences, which, when activated, trigger the production of one of a panel of the reporter enzymes. The enzymes then react with reporter DNA sequences that set off an electrochemical response on the electrode sensor chip.
Peivand Sadat Mousavi, Sarah J. Smith, Jenise B. Chen, Margot Karlikow, Aidan Tinafar, Clare Robinson, Wenhan Liu, Duo Ma, Alexander A. Green, Shana O. Kelley, Keith Pardee. A multiplexed, electrochemical interface for gene-circuit-based sensors. Nature Chemistry, 2019; DOI: 10.1038/s41557-019-0366-y
Posted by Dr. Tim Sandle, Pharmaceutical Microbiology Resources (http://www.pharmamicroresources.com/)