Please use this identifier to cite or link to this item:
標題: The open container-used microfluidic chip using IrO(x) ultramicroelectrodes for the in situ measurement of extracellular acidification
作者: Wu, Ching-Chou
Lin, Wei-Cheng
Fu, Shih-Yu
關鍵字: Microfluidic chip
Acidification rate
Iridium oxide
Potential cycling
iridium oxide-films
ph microelectrode
摘要: The measurement of metabolic activity based on the extracellular acidification rate has attracted wide interests in the field of biochemical detection. In the study, the chip comprising a microfluid-controlled open container and iridium oxide (IrO(x),) pH ultramicroelectrodes (UMEs) was constructed for the purpose of in situ measurement of extracellular acidification rate. The feasible anodic depositing parameters of IrOx film were in the range of +0.53 to +0.8 V by means of exploring the electrochemical properties of alkaline Ir(IV) deposition solution. The IrO(x) pH UMEs electrodeposited for 300 cycles between 0 V and +0.6 V exhibited the near-super-Nernstian sensitivity of -68 to -76 mV/pH and the good stability with potential drifting of 11.7 mV within 24 h. The design of the open container connected with a position-raised microchannel improved the sensing stability of IrO(x), pH UMEs, with the potential deviation of as low as 0.1 mV under the flow rate of 20 mu l/min. The acidification rate of HeLa cells (2160 cells/mm(2)) repeatedly measured 5 times in the microfluidic chip showed the good reproducibility of 0.021 +/- 0.002 pH/min. Moreover, the chip can decrease the acidosis occurrence, a decrease of only 0.13-0.17 pH unit in 8 min interval, during the measurement of cellular metabolic activity. (C) 2011 Elsevier B.V. All rights reserved.
ISSN: 0956-5663
Appears in Collections:生物產業機電工程學系



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.