Real-time lead ion monitoring for drinking water is in an urgent demand, due to the high biotoxicity of lead. We fabricated a reduced graphene oxide (rGO) percolation network based field-effect transistor (FET) by using an easy and scalable micromolding-in-capillary method for lead ion detection in water. The percolation theory analysis elucidates that the required GO mass concentration for a 2D continuum connection converges at a predictable value. Guided by the theoretical analysis, the prepared rGO network was constructed with 1–4 layers of rGO flakes and exhibits comparable electrical properties with single-layer rGO devices. A thin Al2O3layer was deposited on the device to isolate the analyte from the FET device. With the specific L-Glutathione reduced (GSH) probe, the sensor can reach a limit of detection (LOD) in ppb-level to lead ions. In addition, good selectivity and the high sensing response to Pb2+concentrations around 15 ppb (maximum contaminant level of lead for drinking water, US Environmental Protection Agency) suggest our sensor holds great potential for lead ion monitoring in drinking water.
MULTIPLEXED, SELF-CALIBRATED POTENTIOMETRIC SENSOR SYSTEM FOR LONG-TERM, IN SITU MEASUREMENTS
We developed a potentiometric sensor system that includes a portable device and a multiplexed sensor based on solid-contact ion-selective electrodes (SCISE). SCISEs are fabricated using printed circuit board (PCB) and mesoporous carbon black (MCB) as the ion-to-electron transducer. The device supports sensor readout as well as automated sensor calibration, making it suitable for long term, in situ measurements.
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- Award ID(s):
- 1841509
- NSF-PAR ID:
- 10390306
- Date Published:
- Journal Name:
- Proceedings of the 26th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2022)
- Page Range / eLocation ID:
- 1-2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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