title: A planar interdigitated ring electrode array via dielectrophoresis for uniform patterning of cells.
abstract: Uniform patterning of cells is highly desirable for most cellular studies involving cell-cell interactions but is often difficult in an in vitro environment. This paper presents the development of a collagen-coated planar interdigitated ring electrode (PIRE) array utilizing positive dielectrophoresis to pattern cells uniformly. Key features of the PIRE design include: (1) maximizing length along the edges where the localized maximum in the electric field exists; (2) making the inner gap slightly smaller than the outer gap in causing the electric field strength near the center of a PIRE being generally stronger than that near the outer edge of the same PIRE. Results of human hepatocellular carcinoma cells, HepG2, adhered on a 6x6 PIRE array show that cells patterned within minutes with good uniformity (48+/-6 cells per PIRE). Cell viability test revealed healthy patterned cells after 24h that were still confined to the collagen-coated PIREs. Furthermore, quantification of fluorescence intensity of living cells shows an acceptable reproducibility of cell viability among PIREs (mean normalized intensity per PIRE was 1+/-0.138). The results suggest that the PIRE array would benefit applications that desire uniform cellular patterning, and improve both response and reproducibility of cell-based biosensors.
authors.affiliation: Institute of Applied Mechanics, National Taiwan University, Taipei 106, Taiwan, ROC.
authors.forename: Lo-Chang
authors.initials: LC
authors.lastname: Hsiung
authors.forename: Chun-Hui
authors.initials: CH
authors.lastname: Yang
authors.forename: Chi-Li
authors.initials: CL
authors.lastname: Chiu
authors.forename: Chen-Lin
authors.initials: CL
authors.lastname: Chen
authors.forename: Yueh
authors.initials: Y
authors.lastname: Wang
authors.forename: Hsinyu
authors.initials: H
authors.lastname: Lee
authors.forename: Ji-Yen
authors.initials: JY
authors.lastname: Cheng
authors.forename: Ming-Chih
authors.initials: MC
authors.lastname: Ho
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Wo