Open AccessEnzymatic Laser‐Induced Graphene Biosensor for Electrochemical Sensing of the Herbicide Glyphosate
Author(s) -
Johnson Zachary T.,
Jared Nathan,
Peterson John K.,
Li Jingzhe,
Smith Emily A.,
Walper Scott A.,
Hooe Shelby L.,
Breger Joyce C.,
Medintz Igor L.,
Gomes Carmen,
Claussen Jonathan C.
Publication year - 2022
Publication title -
global challenges
Language(s) - English
Resource type - Journals
ISSN - 2056-6646
DOI - 10.1002/gch2.202200057
Subject(s) - glyphosate , detection limit , biosensor , chemistry , choline oxidase , nanotechnology , environmental chemistry , materials science , chromatography , biochemistry , microbiology and biotechnology , biology , enzyme , acetylcholinesterase
Glyphosate is a globally applied herbicide yet it has been relatively undetectable in‐field samples outside of gold‐standard techniques. Its presumed nontoxicity toward humans has been contested by the International Agency for Research on Cancer, while it has been detected in farmers’ urine, surface waters and crop residues. Rapid, on‐site detection of glyphosate is hindered by lack of field‐deployable and easy‐to‐use sensors that circumvent sample transportation to limited laboratories that possess the equipment needed for detection. Herein, the flavoenzyme, glycine oxidase, immobilized on platinum‐decorated laser‐induced graphene (LIG) is used for selective detection of glyphosate as it is a substrate for GlyOx. The LIG platform provides a scaffold for enzyme attachment while maintaining the electronic and surface properties of graphene. The sensor exhibits a linear range of 10–260 µ m , detection limit of 3.03 µ m , and sensitivity of 0.991 nA µ m −1 . The sensor shows minimal interference from the commonly used herbicides and insecticides: atrazine, 2,4‐dichlorophenoxyacetic acid, dicamba, parathion‐methyl, paraoxon‐methyl, malathion, chlorpyrifos, thiamethoxam, clothianidin, and imidacloprid. Sensor function is further tested in complex river water and crop residue fluids, which validate this platform as a scalable, direct‐write, and selective method of glyphosate detection for herbicide mapping and food analysis.