Bio-Inspired Carbon Monoxide Sensors with Voltage-Activated Sensitivity

Angew Chem Int Ed Engl. 2017 Nov 6;56(45):14066-14070. doi: 10.1002/anie.201707491. Epub 2017 Oct 4.

Abstract

Carbon monoxide (CO) outcompetes oxygen when binding to the iron center of hemeproteins, leading to a reduction in blood oxygen level and acute poisoning. Harvesting the strong specific interaction between CO and the iron porphyrin provides a highly selective and customizable sensor. We report the development of chemiresistive sensors with voltage-activated sensitivity for the detection of CO comprising iron porphyrin and functionalized single-walled carbon nanotubes (F-SWCNTs). Modulation of the gate voltage offers a predicted extra dimension for sensing. Specifically, the sensors show a significant increase in sensitivity toward CO when negative gate voltage is applied. The dosimetric sensors are selective to ppm levels of CO and functional in air. UV/Vis spectroscopy, differential pulse voltammetry, and density functional theory reveal that the in situ reduction of FeIII to FeII enhances the interaction between the F-SWCNTs and CO. Our results illustrate a new mode of sensors wherein redox active recognition units are voltage-activated to give enhanced and highly specific responses.

Keywords: Carbon monoxide; carbon nanotubes; iron porphyrin; sensors; voltage-activated.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biosensing Techniques*
  • Carbon Monoxide / analysis*
  • Density Functional Theory
  • Electrochemical Techniques / methods*
  • Limit of Detection
  • Nanotubes, Carbon / chemistry
  • Porphyrins / chemistry
  • Spectrophotometry, Ultraviolet

Substances

  • Nanotubes, Carbon
  • Porphyrins
  • Carbon Monoxide