title: Single-cell bioelectrical impedance platform for monitoring cellular response to drug treatment.
abstract: The response of cells to a chemical or biological agent in terms of their impedance changes in real-time is a useful mechanism that can be utilized for a wide variety of biomedical and environmental applications. The use of a single-cell-based analytical platform could be an effective approach to acquiring more sensitive cell impedance measurements, particularly in applications where only diminutive changes in impedance are expected. Here, we report the development of an on-chip cell impedance biosensor with two types of electrodes that host individual cells and cell populations, respectively, to study its efficacy in detecting cellular response. Human glioblastoma (U87MG) cells were patterned on single- and multi-cell electrodes through ligand-mediated natural cell adhesion. We comparatively investigated how these cancer cells on both types of electrodes respond to an ion channel inhibitor, chlorotoxin (CTX), in terms of their shape alternations and impedance changes to exploit the fine detectability of the single-cell-based system. The detecting electrodes hosting single cells exhibited a significant reduction in the real impedance signal, while electrodes hosting confluent monolayer of cells showed little to no impedance change. When single-cell electrodes were treated with CTX of different doses, a dose-dependent impedance change was observed. This enables us to identify the effective dose needed for this particular treatment. Our study demonstrated that this single-cell impedance system may potentially serve as a useful analytical tool for biomedical applications such as environmental toxin detection and drug evaluation.
authors.affiliation: Department of Materials Science & Engineering, University of Washington, Seattle, WA 98195, USA.
authors.forename: Fareid
authors.initials: F
authors.lastname: Asphahani
authors.forename: Kui
authors.initials: K
authors.lastname: Wang
authors.forename: Myo
authors.initials: M
authors.lastname: Thein
authors.forename: Omid
authors.initials: O
authors.lastname: Veiseh
authors.forename: Sandy
authors.initials: S
authors.lastname: Yung
authors.forename: Jian
authors.initials: J
authors.lastname: Xu
authors.forename: Miqin
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D015374:Biosensing Techniques / Q000295:instrumentation*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004354:Drug Screening Assays, Antitumor / Q000295:instrumentation*; D017097:Electric Impedance; D004566:Electrodes; D004867:Equipment Design; D005909:Glioblastoma / Q000188:drug therapy; D006801:Humans; D012604:Scorpion Venoms / Q000494:pharmacology; D059010:Single-Cell Analysis / Q000295:instrumentation*
chemical_list: D000970:Antineoplastic Agents; D012604:Scorpion Venoms; C091539:Chlorotoxin