In this work, we report a papertronic sensing system with the ability to achieve easy, rapid, and sensitive characterization of bacterial electrogenicity from a single drop of culture. Paper was used as a device substrate that inherently produces favorable conditions for easy, rapid, and sensitive and potentially high-throughput controlling of a microbial liquid sample. Through an innovative microscale device structure and a simple transistor amplifier circuit directly integrated into a single sheet of paper substrate, a powerful sensing array was constructed, resulting in the rapid and sensitive characterization of bacterial electrogenicity from a microliter sample volume. The microbial current generations were amplified by the transistor providing power to a 4-wide LED circuit board indicator bar for the direct visual readout with the naked eyes. Depending on bacterial electrogenicity, the LED intensity was changed. We validated the effectiveness of the sensor using two known bacterial electrogens (wild-type S. oneidensis and P. aeruginosa) and hypothesis-driven genetically modified P. aeruginosa mutant strains.
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An Equipment-Free, Paper-Based Electrochemical Sensor for Visual Monitoring of Glucose Levels in Urine
A novel electrochemical glucose sensor was created for a simple but semiquantitative visual screening of specific glucose concentrations in urine. This noninvasive glucose biosensor integrated a disposable, paper-based sensing strip and a simple amplifier circuit with a visual readout. The paper strip consisted of five enzyme-activated electrodes. Each electrode was connected to a specific indicator circuit that triggered a light-emitting diode (LED) when a predefined glucose concentration was reached. The device features (1) low-cost, disposable, paper-based glucose oxidase (GOx)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) sensing electrodes, (2) simple signal amplification, and (3) on-site, rapid, and visual detection. The sensor generated reliable, discrete visual responses to determine five glucose levels (1, 2, 3, 4, and higher than 4 mM) in urine in less than 2 min. This innovative approach will provide a simple but powerful glucose sensing paradigm for use in POC diagnostics.
more » « less- Award ID(s):
- 1703394
- PAR ID:
- 10115168
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- SLAS TECHNOLOGY: Translating Life Sciences Innovation
- Volume:
- 24
- Issue:
- 5
- ISSN:
- 2472-6303
- Page Range / eLocation ID:
- p. 499-505
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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