title: Carbon nanotube chemiresistor for wireless pH sensing.
abstract: The ability to accurately measure real-time pH fluctuations in-vivo could be highly advantageous. Early detection and potential prevention of bacteria colonization of surgical implants can be accomplished by monitoring associated acidosis. However, conventional glass membrane or ion-selective field-effect transistor (ISFET) pH sensing technologies both require a reference electrode which may suffer from leakage of electrolytes and potential contamination. Herein, we describe a solid-state sensor based on oxidized single-walled carbon nanotubes (ox-SWNTs) functionalized with the conductive polymer poly(1-aminoanthracene) (PAA). This device had a Nernstian response over a wide pH range (2-12) and retained sensitivity over 120 days. The sensor was also attached to a passively-powered radio-frequency identification (RFID) tag which transmits pH data through simulated skin. This battery-less, reference electrode free, wirelessly transmitting sensor platform shows potential for biomedical applications as an implantable sensor, adjacent to surgical implants detecting for infection.
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Pingping
authors.initials: P
authors.lastname: Gou
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Nadine D
authors.initials: ND
authors.lastname: Kraut
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Ian M
authors.initials: IM
authors.lastname: Feigel
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Hao
authors.initials: H
authors.lastname: Bai
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Morgan
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA 15261, United States.
authors.forename: Kara
authors.initials: K
authors.lastname: Bocan
authors.affiliation: Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA 15261, United States.
authors.forename: Joshua
authors.initials: J
authors.lastname: Stachel
authors.affiliation: Ortho-tag Inc., Pittsburgh, PA, United States.
authors.forename: Lee
authors.initials: L
authors.lastname: Berger
authors.affiliation: Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA 15261, United States.
authors.forename: Marlin
authors.initials: M
authors.lastname: Mickle
authors.affiliation: Department of Electrical and Computer Engineering, University of Pittsburgh, Pittsburgh, PA 15261, United States.
authors.forename: Ervin
authors.initials: E
authors.lastname: Sejdić
authors.affiliation: Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15260, United States.
authors.forename: Alexander
authors.initials: A
authors.lastname: Star
mesh_terms: D000138:Acidosis / Q000382:microbiology / Q000473:pathology; D001419:Bacteria / Q000254:growth & development / Q000472:pathogenicity; D015374:Biosensing Techniques; D006801:Humans; D006863:Hydrogen-Ion Concentration; D037742:Nanotubes, Carbon / Q000737:chemistry*; D019736:Prostheses and Implants / Q000382:microbiology*; D059015:Wireless Technology
chemical_list: D037742:Nanotubes, Carbon