Chemical imaging of the concentration profile of ion diffusion in a microfluidic channel

Ko Ichiro Miyamoto, Hiroki Ichimura, Torsten Wagner, Michael J. Schöning, Tatsuo Yoshinobu

Research output: Contribution to journalArticlepeer-review

31 Citations (Scopus)


The chemical imaging sensor is a device to visualize the spatial distribution of chemical species based on the principle of LAPS (light-addressable potentiometric sensor), which is a field-effect chemical sensor based on semiconductor. In this study, the chemical imaging sensor has been applied to investigate the ion profile of laminar flows in a microfluidic channel. The chemical images (pH maps) were collected in a Y-shaped microfluidic channel while injecting HCl and NaCl solutions into two branches. From the chemical images, it was clearly observed that the injected solutions formed laminar flows in the channel. In addition, ion diffusion across the laminar flows was observed, and the diffusion coefficient could be derived by fitting the pH profiles to the Fick's equation.

Original languageEnglish
Pages (from-to)240-245
Number of pages6
JournalSensors and Actuators B: Chemical
Publication statusPublished - 2013


  • Chemical imaging sensor
  • Diffusion coefficient
  • Laminar flow
  • Light-addressable potentiometric sensor
  • Microfluidic channel


Dive into the research topics of 'Chemical imaging of the concentration profile of ion diffusion in a microfluidic channel'. Together they form a unique fingerprint.

Cite this