Design and Development of Microfluidic Based Dielectric Sensors for Biomedical Applications
01 Dec 2019-
TL;DR: In this paper, a microfluidic device capable of sensing even fraction of pico Farad capacitive change is proposed, which is used for fluid concentration identification and characterization based on the dielectric permittivity.
Abstract: A microfluidic device capable of sensing even fraction of pico Farad capacitive change is proposed. Purpose of the developed device is fluid concentration identification and characterization on the basis of the dielectric permittivity. A microchannel, realized on Silicon layer, below a sensing capacitor formed by electrodes sputter printed on a glass substrate. Fluids inside the microchannel affects the capacitance that is measured by a standard electronic interface system. Experimental results obtained for different fluids injected in the microchannel demonstrate the ability of the system to differentiate the fluids and estimate their dielectric permittivity both as pure samples and as mixtures at varying concentration of solute fractions. This makes the device a promising building block for fluid mixing monitoring in microfluidic systems.
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TL;DR: A highly integrated microfluidic chip with the function of DNA amplification is demonstrated, which has the advantages of small size with a high degree of integration, high polymerase chain reaction efficiency, digital control and simple fabrication at low cost.
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55 citations
IBM1
TL;DR: A simple, yet efficient method for monitoring liquid displacement in microfluidic chips using capacitive sensing and a compact, low-cost, and battery-powered device communicating with a smartphone is implemented.
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40 citations
"Design and Development of Microflui..." refers background in this paper
...and biological application has gain enough attraction [1-2]....
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TL;DR: In this article, a microfluidic device with embedded capacitive sensing is proposed for fluid discrimination and characterization in a microchannel on the basis of the dielectric permittivity.
Abstract: A microfluidic device with embedded capacitive sensing is proposed. The purpose of the device is fluid discrimination and characterization in a microchannel on the basis of the dielectric permittivity. The device is fabricated in a hybrid cost-effective technology which innovatively combines PDMS (PolyDiMethylSiloxane) soft photolithography and screen printing techniques. A microchannel, realized in a PDMS layer, is placed in the field of a sensing capacitor formed by electrodes screen-printed on a glass substrate. Fluids inside the microchannel affect the capacitance, that is in the order of femtofarads, which is measured by a tailored electronic interface system. The electronic system features a sensitivity of 100 V/pF and a resolution threshold of 0.06 fF. Experimental results obtained for different fluids injected in the microchannel demonstrate the ability of the system to discriminate the fluids and to estimate their dielectric permittivity both as pure samples and as mixtures at varying solute fractions. This makes the device a promising building block for fluid mixing monitoring in microfluidic systems.
33 citations
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...The dielectric permittivity of different fluids or mixtures affects the capacitance of the electrode [7], which is the parameters being mesaured in our case to estimate the dielectric constant of different fluids....
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...These devices can be made of one or more channel where the desired fluid or tissue sample [3] can be manipulated for analysis....
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"Design and Development of Microflui..." refers background in this paper
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