3.1. ICEK micropumps
Inducing of controlled fluid flow in microchannels without the need for expensive and bulky injection systems is one of the hurdles of designing LOCs, particularly for developing miniaturized and high-throughput (HT) platforms (Dehghan Manshadi, Khojasteh, Mohammadi, & Kamali, 2016). Electrokinetic-based micropumps have a high potential in maintaining the pressure drop along the microchannels due to their simple structure with no need for a moving part, easy fabrication, and integrability on a chip. More importantly, these pumps can generate continuous and precise flow with high controllability and long-term perfusion (Kamali, Manshadi, & Mansoorifar, 2016; Zhou, Zhang, Li, & Wang, 2016). Unlike the conventional electroosmotic flow (EOF) micropumps, ICEK micropumps induce fluid flow in microchannels deliberately with the capability of rapid change of fluid flow with minimal intertia by designing proper polarizable objects/electrodes in both DC and AC electric fields (Todd M. Squires, 2009). Here, the advances in ICEK micropumps are discussed, wherein these pumps are classified as ACEO-based (around polarizable electrodes) and ICEO-based (around polarizable objects) micropumps.