title: Oxygen consumption of cell suspension in a poly(dimethylsiloxane) (PDMS) microchannel estimated by scanning electrochemical microscopy.
abstract: A quantitative analysis of the oxygen concentration profile near a poly(dimethylsiloxane) (PDMS) microfluidic device was performed using scanning electrochemical microscopy (SECM). A microchannel filled with sodium sulfite (Na(2)SO(3)) aqueous solution was imaged by SECM, showing that the oxygen diffusion layer of the PDMS microchannel was observed to be hemicylindrical. Based on a theoretical analysis of the hemicylindrical diffusion layer of the microchannel, the total oxygen mass transfer rates of oxygen to the PDMS microchannel filled with the Na(2)SO(3) solution was calculated to be (4.01 +/- 0.30) x 10(-12) mol s(-1). This is the maximum value of the oxygen transfer rate for this PDMS microchannel device. The oxygen consumption rate increased almost linearly with the logarithm of the concentration of E. coli cells (10(6) approximately 10(8) cells). The respiratory activity for a single E. coli cell was estimated to be approximately 4.31 x 10(-20) mol s(-1) cell(-1).
authors.affiliation: Graduate School of Environmental Studies, Tohoku University, 6-6-11-604 Aramaki, Aoba-ku, Sendai 980-8579, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Saito
authors.forename: Ching-Chou
authors.initials: CC
authors.lastname: Wu
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Shiku
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Yasukawa
authors.forename: Masaki
authors.initials: M
authors.lastname: Yokoo
authors.forename: Takashi
authors.initials: T
authors.lastname: Ito-Sasaki
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Abe
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Hoshi
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Matsue
mesh_terms: D002477:Cells / Q000378:metabolism*; D004058:Diffusion; D004129:Dimethylpolysiloxanes; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods*; D004926:Escherichia coli / Q000378:metabolism; D017022:Flow Injection Analysis / Q000295:instrumentation / Q000379:methods; D008832:Microchemistry / Q000295:instrumentation / Q000379:methods*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D010100:Oxygen / Q000378:metabolism*; D010101:Oxygen Consumption
chemical_list: D004129:Dimethylpolysiloxanes; D010100:Oxygen