An oxidase-based electrochemical fluidic sensor with high-sensitivity and low-interference by on-chip oxygen manipulation

Sensors (Basel). 2012;12(7):8955-65. doi: 10.3390/s120708955. Epub 2012 Jun 29.


Utilizing a simple fluidic structure, we demonstrate the improved performance of oxidase-based enzymatic biosensors. Electrolysis of water is utilized to generate bubbles to manipulate the oxygen microenvironment close to the biosensor in a fluidic channel. For the proper enzyme reactions to occur, a simple mechanical procedure of manipulating bubbles was developed to maximize the oxygen level while minimizing the pH change after electrolysis. The sensors show improved sensitivities based on the oxygen dependency of enzyme reaction. In addition, this oxygen-rich operation minimizes the ratio of electrochemical interference signal by ascorbic acid during sensor operation (i.e., amperometric detection of hydrogen peroxide). Although creatinine sensors have been used as the model system in this study, this method is applicable to many other biosensors that can use oxidase enzymes (e.g., glucose, alcohol, phenol, etc.) to implement a viable component for in-line fluidic sensor systems.

Keywords: biosensor; bubble; electrolysis; hydrogen; oxidase; oxygen.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alcohol Oxidoreductases / chemistry
  • Alcohol Oxidoreductases / metabolism
  • Ascorbic Acid / chemistry
  • Biosensing Techniques*
  • Creatinine / analysis
  • Electrochemical Techniques*
  • Electrolysis
  • Glucose Oxidase / chemistry
  • Glucose Oxidase / metabolism
  • Hydrogen Peroxide / analysis
  • Hydrogen-Ion Concentration
  • Monophenol Monooxygenase / chemistry
  • Monophenol Monooxygenase / metabolism
  • Oxidoreductases / chemistry
  • Oxidoreductases / metabolism*
  • Oxygen / chemistry
  • Oxygen / metabolism*


  • Creatinine
  • Hydrogen Peroxide
  • Oxidoreductases
  • Alcohol Oxidoreductases
  • alcohol oxidase
  • Glucose Oxidase
  • Monophenol Monooxygenase
  • Ascorbic Acid
  • Oxygen