title: Electrical characterization of single cells using polysilicon wire ion sensor in an isolation window.
abstract: A polysilicon wire (PSW) sensor can detect the H(+) ion density (pH value) of the medium coated on its surface, and different cells produce different extracellular acidification and hence different H(+) ion densities. Based on this, we used a PSW sensor in combination with a mold-cast polydimethylsiloxane (PDMS) isolation window to detect the adhesion, apoptosis and extracellular acidification of single normal cells and single cancer cells. Single living human normal cells WI38, MRC5, and BEAS-2B as well as non-small-cell lung cancer (NSCLC) cells A549, H1299, and CH27 were cultivated separately inside the isolation window. The current flowing through the PSW channel was measured. From the PSW channel current change as a function of time, we determined the cell adhesion time by observing the time required for the current change to saturate, since a stable extracellular ion density was established after the cells were completely adhered to the PSW surface. The apoptosis of cells can also be determined when the channel current change drops to zero. We found that all the NSCLC cells had a higher channel current change and hence a lower pH value than the normal cells anytime after they were seeded. The corresponding average pH values were 5.86 for A549, 6.00 for H1299, 6.20 for CH27, 6.90 for BEAS-2B, 6.96for MRC5, and 7.02 for WI38, respectively, after the cells were completely adhered to the PSW surface. Our results show that NSCLC cells have a stronger cell-substrate adhesion and a higher extracellular acidification rate than normal cells.
authors.affiliation: Department of Electrical Engineering, National Chi Nan University, Puli, Nantou 54561, Taiwan ROC. ylwu@ncnu.edu.tw
authors.forename: You-Lin
authors.initials: YL
authors.lastname: Wu
authors.forename: Po-Yen
authors.initials: PY
authors.lastname: Hsu
authors.forename: Chung-Ping
authors.initials: CP
authors.lastname: Hsu
authors.forename: Chih-Cheng
authors.initials: CC
authors.lastname: Wang
authors.forename: Li-Wen
authors.initials: LW
authors.lastname: Lee
authors.forename: Jing-Jenn
authors.initials: JJ
authors.lastname: Lin
mesh_terms: D017209:Apoptosis; D002289:Carcinoma, Non-Small-Cell Lung / Q000473:pathology; D002448:Cell Adhesion; D003585:Cell Biology / Q000295:instrumentation*; D045744:Cell Line, Tumor; D004129:Dimethylpolysiloxanes; D004559:Electric Wiring; D004867:Equipment Design; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008175:Lung Neoplasms / Q000473:pathology; D012016:Reference Values
chemical_list: D004129:Dimethylpolysiloxanes; C013830:baysilon