Ultrasensitive visual read-out of nucleic acids using electrocatalytic fluid displacement

Justin D. Besant, Jagotamoy Das, Ian B. Burgess, Wenhan Liu, Edward H. Sargent, Shana O. Kelley*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

19 Scopus citations


Diagnosis of disease outside of sophisticated laboratories urgently requires low-cost, user-friendly devices. Disposable, instrument-free testing devices are used for home and physician office testing, but are limited in applicability to a small class of highly abundant analytes. Direct, unambiguous visual read-out is an ideal way to deliver a result on a disposable device; however, existing strategies that deliver appropriate sensitivity produce only subtle colour changes. Here we report a new approach, which we term electrocatalytic fluid displacement, where a molecular binding event is transduced into an electrochemical current, which drives the electrodeposition of a metal catalyst. The catalyst promotes bubble formation that displaces a fluid to reveal a high contrast change. We couple the read-out system to a nanostructured microelectrode and demonstrate direct visual detection of 100 fM DNA in 10 min. This represents the lowest limit of detection of nucleic acids reported using high contrast visual read-out.

Original languageEnglish (US)
Article number6978
JournalNature communications
StatePublished - Apr 22 2015

ASJC Scopus subject areas

  • General Chemistry
  • General Biochemistry, Genetics and Molecular Biology
  • General Physics and Astronomy


Dive into the research topics of 'Ultrasensitive visual read-out of nucleic acids using electrocatalytic fluid displacement'. Together they form a unique fingerprint.

Cite this