CMOS Enabled Microfluidic Systems for Healthcare Based Applications

Sherjeel M. Khan, Abdurrahman Gumus, Joanna M. Nassar, Muhammad M. Hussain
2018 Advanced Materials  
additional parts, such as syringe pumps, control valves, and microscopes, which not only increase the complexity and cost of the system but also create a dependence of the system on a laboratorybased environment. Technology has now advanced so much that there are fully integrated sample-in-results-out chips for genetic analysis, [8] sensors that can detect a handful of molecules, and many other similar systems. [9] Complementary metal oxide semiconductor (CMOS) integrated LOC systems can be
more » ... loped using CMOS technologies as sensors, signal conditioners, data processing circuitry, actuators, and wireless communication capabilities. [10] [11] [12] [13] [14] [15] [16] [17] CMOS is a set of microfabrication and nanofabrication processes, which is used to manufacture semiconductor chips present inside computer, smartphone, or any electronic gadgets. Consequently, these chips are referred to as CMOS enabled or CMOS based chips. CMOS based chips can act as a processor, memory, and digital logic circuitry for data management. In this review, we will discuss how CMOS based devices have enabled both management of data from microfluidic devices as well as sensors and actuators to help complement the functionality of LOC devices. CMOS logics are simple to make, and consume little to no current in idle state. With the advancements in Moore's law we have seen the size of CMOS devices getting smaller and smaller allowing for more functionality to fit in a smaller area. [18] CMOS plays a significant role in the realization of portable and versatile microfluidic platforms by integrating them with microscale sensors, interfaces, and actuators to form autonomous hybrid systems. [10, 12, 16] Adding interface electronics to the same CMOS chip as sensors, actuators, data processing, and communication capabilities creates a universal platform for LOC technologies. Having signal amplification and noise removal right at the sensor interface without any signal loss makes the device output more accurate and sensitive, and also removes parasitic and mismatch errors. [1] By using CMOScompatible processes, it is possible to interface directly with the readout circuitry to form an integrated circuit system on a single chip. Signal acquisition from a large array of sensors to a single system requires a complex integration scheme, but CMOS microfabrication processes enable the integration of analogue multiplexers with biosensors on small dice. [19] CMOS also has the capability to actuate pumps and valves in microfluidic devices or to directly influence the fluid itself using electric With the increased global population, it is more important than ever to expand accessibility to affordable personalized healthcare. In this context, a seamless integration of microfluidic technology for bioanalysis and drug delivery and complementary metal oxide semiconductor (CMOS) technology enabled data-management circuitry is critical. Therefore, here, the fundamentals, integration aspects, and applications of CMOS-enabled microfluidic systems for affordable personalized healthcare systems are presented. Critical components, like sensors, actuators, and their fabrication and packaging, are discussed and reviewed in detail. With the emergence of the Internet-of-Things and the upcoming Internet-of-Everything for a people-process-datadevice connected world, now is the time to take CMOS-enabled microfluidics technology to as many people as possible. There is enormous potential for microfluidic technologies in affordable healthcare for everyone, and CMOS technology will play a major role in making that happen. We further discuss the integration challenges associated with such devices and present a comprehensive review of packaging techniques used to overcome those challenges. We also present our perspective on the challenges and future trends for next-generation CMOS-microfluidic systems, which include flexible and stretchable integrated CMOS technologies and lowcost paper-based unconventional LOC systems. We outline the role of CMOS technologies and the factors that may affect their deployment in new directions for microfluidic systems. Finally, a number of CMOS based LOC applications and devices are shown that have made a significant contribution toward an improvement in the clinical outcomes. Microfluidic Systems A microfluidic system is composed of channels, valves, chambers, mixers, and sorters working together in harmony to perform a complex set of tasks, predominantly focusing on biological and healthcare applications. [32] Generally, a
doi:10.1002/adma.201705759 pmid:29484725 fatcat:fvsk27zm5bamvd7wziii4u7o7y