Project TitleAutonomous, Calibration-less, Remote, Electrochemical Detection of Metals in Water and Other Liquids (15058)
Track Code15058
Short Description



Features and Benefits

  • Calibration-less, automatic, remote monitoring of heavy metal content in water or other solutions (no operator required)
  • Requires minimal reagents and sample pretreatment (does not require standards, a blank solution, etc.)
  • Durable, reusable and relatively inexpensive to manufacture sensor devices
  • Tunable selectivity for metals such as As, Pb Hg, and Cd; which are #1, 2, 3, 7, respectively, amongst hundreds of prioritized hazardous substances at superfund sites (1,5)


*This technology is available for licensing, further development, or industrial partnering




University of Louisville researchers are developing calibration-less, automatic sensors and methods to enable continuous remote monitoring of heavy metal content in water and other samples. A finite volume stopped flow thin-layer cell employs anodic stripping coulometry (ASC), after exhaustive preconcentration of dissolved metals in the cell volume on the electrode surface for determination of metals through electrolysis. The measured stripping charge along with the known cell volume enable simple calculation of the dissolved metal concentration using Faraday’s law – without any calibration. Subtraction of background (due to the charging current) is accomplished in situ using a double potential step ASC (DPS-ASC) variant, without the need for a ‘blank’ electrolyte. For arsenite and other metal species of interest, the coulometric response is linear between about 100-1000 ppb for the last sensor generation; whereas the current generation is capable of detecting low ppb metal levels. (2, 3)




To impart selectivity, DPS-ASC can be performed at multiple deposition potentials to quantitatively resolve the contributions of individual metals from the total stripping signal. This technology provides for exhaustive deposition in a short time frame (one to a few minutes), provides desirable selectivity, and is tolerant of possible interferences by other metals present in the sample. The sensor devices, which are are relatively inexpensive to manufacture, show great promise for large-scale decentralized remote monitoring of metals in natural waters without the need for frequent, hands-on operator intervention. (4)


Markets Addressed


The global market for air and water monitoring products is estimated to exceed $25 billion by 2017, up from $22 billion in 2013. Revenues are expected to increase indirectly from lower energy cost and the construction of new chemical, fertilizer, and metal processing plants. Additionally, the developing world is increasing its expenditures for ambient monitoring of air and water, pegging detection of toxic materials as the first step toward their reduction.


Technology Status

  • IP Status: Patent pending
  • Development Status: Method developed, working prototype designed, fabricated, and successful operation demonstrated



  1. Marei, Mohamed M., 2014, “Electrochemical and microfabrication strategies for remotely operated heavy metal sensor networks for water analysis: The dual challenges of calibration-less measurement and sample pretreatment,” PhD dissertation, University of Louisville, available at (accessed April 7, 2015):
  2. M.M. Marei, T.J. Roussel, R.S. Keynton, R.P. Baldwin. Measuring Low ppb [As(III)] from 2-4μL Samples in Two Minutes, Without Calibration and No Need for a Blank Electrolyte in the Presence of Other Metal Interferents. PITTCON Conference & Expo, March 8-12, 2015. New Orleans, LA USA
  3. M.M. Marei, T.J. Roussel, R.S. Keynton, R.P. Baldwin. Electrochemical Determination of As(III) by Subtractive Anodic Stripping Coulometry in a Micro-fabricated Platform. PITTCON Conference & Expo, March 2-6, 2014. Chicago, IL USA
  4. T.J. Roussel, M.M. Marei, R.S. Keynton, R.P. Baldwin. Development of a Solar-Powered, Microcontroller-Based, Remotely Deployable Potentiostat for In-the-field Electrochemical Analysis of Heavy Metals. PITTCON Conference & Expo, March 8-12, 2015. New Orleans, LA USA
  5. Agency for Toxic Substance and Disease Registry. Available on the web at (accessed April 7, 2015):
Posted DateApr 3, 2015 5:29 PM


Richard Baldwin
Thomas Roussel
Robert Keynton
Mohamed Marei


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15058 Marketing Abstract Marketing abstract for technology 15058 in .pdf Download
Figure 1 4-3-2015.JPG Anodic stripping coulometry platform Download
UL_photo.png University of Louisville mark - protected. Download