As the use of pesticides in agriculture is increasing at an alarming rate, food contamination by pesticide residues is becoming a huge global problem. It is essential to develop a sensitive and user-friendly sensor device to quantify trace levels of pesticide and herbicide residues in food samples. Herein, we report an electrocatalyst made up of yttrium iron garnet (Y3Fe5O12; YIG) and graphitic carbon nitride (GCN) to attain picomolar-level detection sensitivity for mesotrione (MTO), which is a widely used herbicide in agriculture. First, YIG was prepared by a hydrothermal route; then, it was loaded on GCN sheets via a calcination method. The surface structures, composition, crystallinity, and interfacial and electrocatalytic properties of the YIG and YIG/GCN were analyzed. As the YIG/GCN displayed better surface and catalytic properties than YIG, YIG/GCN was modified on a screen-printed carbon electrode to fabricate a sensor for MTO. The YIG/GCN-modified electrode displayed a detection limit of 950 pM for MTO. The method was demonstrated in (spiked) fruits and vegetables. Then, the modified electrode was integrated with a miniaturized potentiostat called KAUSTat, which can be operated wirelessly by a smartphone. A first smartphone-based portable sensor was demonstrated for MTO that is suitable for use in nonlaboratory settings.
|Original language||English (US)|
|Journal||ACS Applied Materials & Interfaces|
|State||Published - May 19 2021|
Bibliographical noteKAUST Repository Item: Exported on 2021-05-25
Acknowledgements: This work was supported by the Ministry of Science and Technology and National Taipei University of Technology, Taiwan, and King Abdullah University of Science and Technology (KAUST), Saudi Arabia. The authors thank Prof. Khaled N. Salama, KAUST, for his valuable suggestions regarding smartphone sensing platform.
ASJC Scopus subject areas
- Materials Science(all)