title: Metal-coated microfluidic channels: An approach to eliminate streaming potential effects in nano biosensors.
abstract: We report a method to suppress streaming potential using an Ag-coated microfluidic channel on a p-type silicon nanowire (SiNW) array measured by a multiplexed electrical readout. The metal layer sets a constant electrical potential along the microfluidic channel for a given reference electrode voltage regardless of the flow velocity. Without the Ag layer, the magnitude and sign of the surface potential change on the SiNW depends on the flow velocity, width of the microfluidic channel and the device's location inside the microfluidic channel with respect to the reference electrode. Noise analysis of the SiNW array with and without the Ag coating in the fluidic channel shows that noise frequency peaks, resulting from the operation of a piezoelectric micropump, are eliminated using the Ag layer with two reference electrodes located at inlet and outlet. This strategy presents a simple platform to eliminate the streaming potential and can become a powerful tool for nanoscale potentiometric biosensors.
authors: Department of Electrical Engineering, Yale University, New Haven, CT 06511, United States.
authors: Jieun
authors: J
authors: Lee
authors: Department of Electrical Engineering, Yale University, New Haven, CT 06511, United States.
authors: Mathias
authors: M
authors: Wipf
authors: Department of Electrical Engineering, Yale University, New Haven, CT 06511, United States.
authors: Luye
authors: L
authors: Mu
authors: QuantuMDx Group, Newcastle NE1 2JQ, United Kingdom.
authors: Chris
authors: C
authors: Adams
authors: QuantuMDx Group, Newcastle NE1 2JQ, United Kingdom.
authors: Jennifer
authors: J
authors: Hannant
authors: Department of Electrical Engineering, Yale University, New Haven, CT 06511, United States; Department of Applied Physics, Yale University, New Haven, CT 06511, United States. Electronic address: mark.reed@yale.edu.
authors: Mark A
authors: MA
authors: Reed
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004553:Electric Conductivity; D004566:Electrodes; D004867:Equipment Design; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D053770:Nanowires / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*
chemical_list: D012834:Silver; D012825:Silicon
keywords: Metal thin film; Microfluidic channel; Multiplexed electrical readout; Silicon nanowire biosensors; Streaming potential