A disposable on-chip phosphate sensor with planar cobalt microelectrodes on polymer substrate.
Zhiwei Zou1, Jungyoup Han, Am Jang
1Microsystems and BioMEMS Laboratory, Department of Electrical and Computer Engineering, University of Cincinnati, Cincinnati, OH 45221-0030, USA. zouz@ececs.uc.edu
Biosensors & Bioelectronics
|September 19, 2006
Summary
This study presents a novel disposable microsensor for accurate phosphate measurement. The cost-effective, polymer-based sensor demonstrates high selectivity and reproducibility for both inorganic and organic phosphate compounds.
Area of Science:
- Electrochemistry
- Materials Science
- Analytical Chemistry
Background:
- Phosphate measurement is crucial for environmental and clinical applications.
- Existing methods may lack selectivity, cost-effectiveness, or ease of use.
- Development of integrated, disposable sensors is needed for point-of-care diagnostics and field analysis.
Purpose of the Study:
- To design, fabricate, and characterize a disposable polymer-based microsensor for phosphate concentration measurement.
- To evaluate the sensor's selectivity, sensitivity, reproducibility, and stability.
- To highlight the advantages of the integrated microsensor for diverse applications.
Main Methods:
- Fabrication of disposable polymer microsensors with integrated planar cobalt (Co) microelectrodes, Ag/AgCl reference electrodes, and microfluidic channels.
- Characterization of the Co microelectrode's potential response to inorganic (KH(2)PO(4)) and organic (ATP, ADP) phosphate compounds in an acidic medium (pH 5.0).
- Assessment of sensor reproducibility using relative standard deviation (R.S.D.) for single-chip and chip-to-chip measurements.
Main Results:
- The planar Co microelectrode exhibited selective potential response to phosphate compounds in the concentration range of 10(-5) to 10(-2)M.
- The microsensor demonstrated high reproducibility with R.S.D. <1% on-chip and R.S.D. <2.5% chip-to-chip.
- The sensor maintained selectivity, sensitivity, and stability comparable to conventional bulk Co-wire electrodes.
Conclusions:
- The developed disposable microsensor offers a cost-effective, user-friendly alternative for phosphate detection.
- Its ability to detect both inorganic and organic phosphates enhances its applicability in environmental monitoring, soil analysis, and clinical diagnostics.
- The sensor's integration into lab-on-a-chip devices facilitates diverse analytical applications with reduced analyte consumption.
