title: Label-free enumeration of colorectal cancer cells from lymphocytes performed at a high cell-loading density by using interdigitated ring-array microelectrodes.
abstract: We report the label-free enumeration of human colorectal-carcinoma cells from blood lymphocytes by using interdigitated ring-array microelectrodes; this enumeration was based on the dielectrophoretic selection of cells. Because of the novel design of the device, a continuous flow of cells is uniformly distributed into parallel streams through 300 rings (~40 μm in diameter each) that are integrated into the electrode digits. Using this array, 82% of cancer cells were recovered and 99% of blood lymphocytes were removed. Most of the cancer cells recovered were viable (94%) and could be cultivated for >8 days, during which period they retained their normal cell morphology and proliferation rates. The recovery rate correlated closely with cancer-cell loadings in spiked samples and this relationship was linear over a range of at least 2 orders of magnitude. Importantly, because of the 3D structure of the rings, these results were obtained at a high cell-loading concentration (10(7)cells/mL). The rings could be further optimized for use in accurate label-free identification and measurement of circulating tumor cells in cancer research and disease management.
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Special Administrative Region.
authors.forename: Xiaoxing
authors.initials: X
authors.lastname: Xing
authors.affiliation: Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Special Administrative Region.
authors.forename: Randy Y C
authors.initials: RY
authors.lastname: Poon
authors.affiliation: Department of Health Technology and Informatics, Faculty of Health and Social Sciences, Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Special Administrative Region.
authors.forename: Cesar S C
authors.initials: CS
authors.lastname: Wong
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Special Administrative Region. Electronic address: eelyobas@ust.hk.
authors.forename: Levent
authors.initials: L
authors.lastname: Yobas
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D002452:Cell Count; D045744:Cell Line, Tumor; D002469:Cell Separation / Q000295:instrumentation*; D015179:Colorectal Neoplasms / Q000097:blood* / Q000473:pathology; D004586:Electrophoresis / Q000295:instrumentation; D004867:Equipment Design; D006801:Humans; D008214:Lymphocytes / Q000166:cytology; D008839:Microelectrodes; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009360:Neoplastic Cells, Circulating / Q000473:pathology*
keywords: Cancer; Cells; Dielectrophoresis; Electrode; Microfluidics; Silicon