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Updated: Jan 23, 2026

Large Volume 20L+ Filtration of Coastal Seawater Samples
Published on: June 18, 2009
A feedback-controlling digital microfluidic fluorimetric sensor device for simple and rapid detection of mercury (II)
Qian Zhang1, Xingcai Zhang2, Xiaolin Zhang1
1Chemical and Environmental Engineering Institute, Dalian University, Dalian 116622, China; Environmental Micro Total Analysis Lab, Dalian University, Dalian 116622, China.
Abstract:
By combination of miniaturization potential of digital microfluidics (DMF) and sensitivity of fluorescence probe, an integrated sensor device has been initially constructed for mercury detection in coastal waters. The actuation feature of the detecting target, seawater droplet, which remains unclear, was basically explored. To overcome a potential risk of driven failure, induced by diversity ion ingredients in seawater, a feedback control loop was included into control system. Analyzing method for coastal waters was well established on DMF, which showed satisfied stability and selectivity in Hg sensing under high salinity condition, with the sensitivity of Hg2+ at the parts per billion level and total testing time less than 20s. With the advantages of being fast, amenable to automation and low cost, this device is promising for the formation of simple and rapid sensor device, especially for a routine monitoring and emergency detection of Hg/or other metals in coastal waters.
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