Bioelectronic protein nanowire sensors for ammonia detection


Electronic sensors based on biomaterials can lead to novel green technologies that are low cost, renewable, and eco-friendly. Here we demonstrate bioelectronic ammonia sensors made from protein nanowires harvested from the microorganism Geobacter sulfurreducens. The nanowire sensor responds to a broad range of ammonia concentrations (10 to 106 ppb), which covers the range relevant for industrial, environmental, and biomedical applications. The sensor also demonstrates high selectivity to ammonia compared to moisture and other common gases found in human breath. These results provide a proof-of-concept demonstration for developing protein nanowire based gas sensors for applications in industry, agriculture, environmental monitoring, and healthcare.

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J. Y. and D. R. L. acknowledge support from a seed fund through the Office of Technology Commercialization and Ventures at the University of Massachusetts, Amherst. J. Y. acknowledges the support from a National Science Foundation (NSF) Award ECCS-1917630. J. M. J. acknowledges support from a NSF grants CAREER CMMI1842308. A. F. S. acknowledges the support from a NSF Graduate Research Fellowship (No. S12100000000937). Part of the device fabrication work was conducted in the clean room of the Center for Hierarchical Manufacturing (CHM), an NSF Nanoscale Science and Engineering Center (NSEC) located at the University of Massachusetts, Amherst.

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Correspondence to Derek R. Lovley or Jun Yao.

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Smith, A.F., Liu, X., Woodard, T.L. et al. Bioelectronic protein nanowire sensors for ammonia detection. Nano Res. 13, 1479–1484 (2020).

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  • nanowire
  • protein nanowire
  • biomaterial
  • bioelectronics
  • biosensor
  • ammonia sensor