title: Real-time electrical detection of nitric oxide in biological systems with sub-nanomolar sensitivity.
abstract: Real-time monitoring of nitric oxide concentrations is of central importance for probing the diverse roles of nitric oxide in neurotransmission, cardiovascular systems and immune responses. Here we report a new design of nitric oxide sensors based on hemin-functionalized graphene field-effect transistors. With its single atom thickness and the highest carrier mobility among all materials, graphene holds the promise for unprecedented sensitivity for molecular sensing. The non-covalent functionalization through π-π stacking interaction allows reliable immobilization of hemin molecules on graphene without damaging the graphene lattice to ensure the highly sensitive and specific detection of nitric oxide. Our studies demonstrate that the graphene-hemin sensors can respond rapidly to nitric oxide in physiological environments with a sub-nanomolar sensitivity. Furthermore, in vitro studies show that the graphene-hemin sensors can be used for the detection of nitric oxide released from macrophage cells and endothelial cells, demonstrating their practical functionality in complex biological systems.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, USA.
authors.forename: Shan
authors.initials: S
authors.lastname: Jiang
authors.forename: Rui
authors.initials: R
authors.lastname: Cheng
authors.forename: Xiang
authors.initials: X
authors.lastname: Wang
authors.forename: Teng
authors.initials: T
authors.lastname: Xue
authors.forename: Yuan
authors.initials: Y
authors.lastname: Liu
authors.forename: Andre
authors.initials: A
authors.lastname: Nel
authors.forename: Yu
authors.initials: Y
authors.lastname: Huang
authors.forename: Xiangfeng
authors.initials: X
authors.lastname: Duan
mesh_terms: D000818:Animals; D001920:Bradykinin / Q000494:pharmacology; D002460:Cell Line; D055664:Electrochemical Techniques; D006108:Graphite / Q000737:chemistry*; D006427:Hemin / Q000737:chemistry*; D061307:Human Umbilical Vein Endothelial Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D006801:Humans; D008070:Lipopolysaccharides / Q000494:pharmacology; D008264:Macrophages / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000032:analysis* / Q000096:biosynthesis; D012680:Sensitivity and Specificity; D013997:Time Factors; D014173:Transistors, Electronic
chemical_list: D008070:Lipopolysaccharides; D009569:Nitric Oxide; D006427:Hemin; D006108:Graphite; D001920:Bradykinin; D019331:NG-Nitroarginine Methyl Ester