title: Capacitance variation induced by microfluidic two-phase flow across insulated interdigital electrodes in lab-on-chip devices.
abstract: Microfluidic two-phase flow detection has attracted plenty of interest in various areas of biology, medicine and chemistry. This work presents a capacitive sensor using insulated interdigital electrodes (IDEs) to detect the presence of droplets in a microchannel. This droplet sensor is composed of a glass substrate, patterned gold electrodes and an insulation layer. A polydimethylsiloxane (PDMS) cover bonded to the multilayered structure forms a microchannel. Capacitance variation induced by the droplet passage was thoroughly investigated with both simulation and experimental work. Olive oil and deionized water were employed as the working fluids in the experiments to demonstrate the droplet sensor. The results show a good sensitivity of the droplet with the appropriate measurement connection. This capacitive droplet sensor is promising to be integrated into a lab-on-chip device for in situ monitoring/counting of droplets or bubbles.
authors: Institute of Applied Micro-Nano Science and Technology, Chongqing Technology and Business University, Chongqing 400067, China. tao.dong@ctbu.edu.cn.
authors: Tao
authors: T
authors: Dong
authors: Department of Micro and Nano Systems Technology (IMST), Faculty of Technology and Maritime Sciences (TekMar), Buskerud and Vestfold University College (HBV), Borre 3184, Norway.
authors: Cátia
authors: C
authors: Barbosa
mesh_terms: D003198:Computer Simulation; D025802:Electric Capacitance; D066292:Lipid Droplets / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques; D014867:Water / Q000737:chemistry
chemical_list: D014867:Water
references: Biomicrofluidics. 2007 Oct 03;1(4):44101
references: 19693400
references: Annu Rev Anal Chem (Palo Alto Calif). 2012;5:413-40
references: 22524226
references: Anal Chim Acta. 2009 Apr 13;638(2):115-25
references: 19327449
references: Curr Opin Biotechnol. 2010 Aug;21(4):517-23
references: 20829028
references: Drug Discov Today. 2008 Jan;13(1-2):1-13
references: 18190858
references: Lab Chip. 2004 Oct;4(5):473-80
references: 15472731
references: Angew Chem Int Ed Engl. 2012 Dec 3;51(49):12176-92
references: 23180509
references: Lab Chip. 2006 Dec;6(12):1487-503
references: 17203152
references: Lab Chip. 2008 Feb;8(2):198-220
references: 18231657
references: Chem Commun (Camb). 2011 Feb 21;47(7):1936-42
references: 20967373
references: Biomed Mater Eng. 2014;24(1):77-83
references: 24211885
references: J Biomed Opt. 2011 Aug;16(8):080901
references: 21895307
references: Anal Chem. 2012 Oct 16;84(20):8541-8
references: 22985130
references: Anal Chim Acta. 2007 Oct 10;601(2):141-55
references: 17920386
references: Lab Chip. 2012 Feb 7;12(3):602-12
references: 22146918