A CMOS micro-flow cytometer for magnetic label detection and classification

Flow cytometry is widely used in medicine for hematology, immunology, chemotherapy and pathology, as well as in food and water safety. While present instruments are predominantly used in laboratory environments, there is a growing and unmet need for devices that can be used in point-of-care (PoC) settings. The main impediments to PoC solutions are the fluorescent labels, which require sophisticated sample pre-processing and calibration to reduce background, and optics that are difficult to miniaturize. Label-free approaches such as reported in [1] eliminate this problem but have limited applications due to a lack of specificity. Substituting magnetic labels avoids this limitation and eliminates the need for preprocessing, but present solutions use μHall sensors [2] or giant-magneto-resistors (GMRs) [3], which are not available in standard CMOS technology. CMOS LC-tank spectrometry [4] is amenable to integration but does not achieve the bandwidth and sensitivity required for flow cytometry. In this paper, we present a magnetic flow cytometer integrated in standard CMOS technology assembled in a single-use microfluidic cartridge that meets all the above-mentioned requirements.