A Review on Microfluidics-Based Impedance Biosensors

Abstract

Electrical impedance biosensors are powerful and continuously being developed for various biological sensing applications. In this line, the sensitivity of impedance biosensors embedded with microfluidic technologies, such as sheath flow focusing, dielectrophoretic focusing, and interdigitated electrode arrays, can still be greatly improved. In particular, reagent consumption reduction and analysis time-shortening features can highly increase the analytical capabilities of such biosensors. Moreover, the reliability and efficiency of analyses are benefited by microfluidics-enabled automation. Through the use of mature microfluidic technology, complicated biological processes can be shrunk and integrated into a single microfluidic system (e.g., lab-on-a-chip or micro-total analysis systems). By incorporating electrical impedance biosensors, hand-held and bench-top microfluidic systems can be easily developed and operated by personnel without professional training. Furthermore, the impedance spectrum provides broad information regarding cell size, membrane capacitance, cytoplasmic conductivity, and cytoplasmic permittivity without the need for fluorescent labeling, magnetic modifications, or other cellular treatments. In this review article, a comprehensive summary of microfluidics-based impedance biosensors is presented. The structure of this article is based on the different substrate material categorizations. Moreover, the development trend of microfluidics-based impedance biosensors is discussed, along with difficulties and challenges that may be encountered in the future.

Microfluidic Electrochemical Glucose Biosensor with In Situ Enzyme Immobilization

“…There are numerous strategies to design and fabricate miniaturized biosensors. One of them is microfluidics, which has been widely explored [ 3 , 19 , 20 , 21 , 22 ]. Integrating a biosensor into a microfluidic chip brings miniaturization with extremely low sample consumption and continuous measurement of the analyte.…”

Single-cell impedance cytometry of anticancer drug-treated tumor cells exhibiting mitotic arrest state to apoptosis using low-cost silver-PDMS microelectrodes

“…On the other hand, electrode configurations play a vital role in a MIC device, as have been reviewed comprehensively in recent review papers. 30,31 Coplanar metal electrodes patterned 11,15,16,20 on the channel floor or parallel electrodes aligned face-to-face on the channel top and bottom 12,14,17,19 are the most popular designs. Yet, these electrodes require standard cleanroom processes such as metal evaporation and lift-off as well as aligned and leak-free bonding, which gain the cost and complexity of fabrication.…”

Analysis of Cellular Crosstalk and Molecular Signal between Periosteum-Derived Precursor Cells and Peripheral Cells During Bone Healing Process Using a Paper-Based Osteogenesis-On-A-Chip Platform

“…As the mature development of microfabrication technology, microfluidics has been shown to be a promising technique for precise analysis of cellular activities. – Moreover, three-dimensional (3D) culture was proposed to provide a more physiologically relevant culture model . Microfluidic-based 3D microenvironment was constructed for bone tissue engineering. – These culture approaches provided more biomimetic tissue culture conditions for understanding the biology of bone, as well as bone-related diseases and treatments.…”