title: A portable microfluidic flow cytometer based on simultaneous detection of impedance and fluorescence.
abstract: A portable microfluidic flow cytometer with dual detection ability of impedance and fluorescence was developed for cell analysis and particle-based assays. In the proposed system, fluorescence from microparticles and cells is measured through excitation by a light emitting diode (LED) and detection by a solid-stated photomultiplier (SSPM). Simultaneous impedometric detection provides information on the existence and size of microparticles and cells through polyelectrolyte gel electrodes (PGEs) operated by custom designed circuits for signal detection, amplification, and conversion. Fluorescence and impedance signals were sampled at 1 kHz with 12 bit resolution. The resulting microfluidic cytometer is 15x10x10 cm(3) in width, depth, and height, with a weight of about 800 g. Such a miniaturized and battery powered system yielded a portable microfluidic cytometer with high performance. Various microbeads and human embryonic kidney 293 (HEK-293) cells were employed to evaluate the system. Impedance and fluorescence signals from each bead or cell made classification of micro particles or cells easy and fast.
authors.affiliation: Department of Biomedical Engineering, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea.
authors.forename: Segyeong
authors.initials: S
authors.lastname: Joo
authors.forename: Kee Hyun
authors.initials: KH
authors.lastname: Kim
authors.forename: Hee Chan
authors.initials: HC
authors.lastname: Kim
authors.forename: Taek Dong
authors.initials: TD
authors.lastname: Chung
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D003217:Conductometry / Q000295:instrumentation*; D017097:Electric Impedance; D004867:Equipment Design; D019544:Equipment Failure Analysis; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008904:Miniaturization; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*