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Bias-dependent photocurrent response in protein nanolayer-embedded solid state planar diode devices
Sungho Nam1, Hwajeong Kim, Youngkyoo Kim
1Organic Nanoelectronics Laboratory, Department of Chemical Engineering, Kyungpook National University, Daegu, 702-701, Republic of Korea.
Nanoscale
|July 22, 2010
Summary
Planar diodes with a horseradish peroxidase (HRP) protein nanolayer showed a bias-dependent superlinear photocurrent response under white light. This finding is significant for developing biosensors for hydrogen peroxide detection in biological systems.
Area of Science:
- Biophysics
- Materials Science
- Biosensing
Background:
- Horseradish peroxidase (HRP) is crucial for detecting hydrogen peroxide in biological contexts.
- Photocurrent responses in organic electronic devices are vital for optoelectronic applications.
Purpose of the Study:
- To investigate the photocurrent response of planar diodes incorporating a horseradish peroxidase (HRP) protein nanolayer.
- To analyze the bias-dependent and superlinear characteristics of this response under white light illumination.
Main Methods:
- Fabrication of planar diodes with a HRP protein nanolayer.
- Measurement of photocurrent under varying bias conditions and white light exposure.
Main Results:
- A distinct bias-dependent superlinear photocurrent response was observed.
- The HRP protein nanolayer significantly influenced the device's optoelectronic properties.
Conclusions:
- The HRP-based diodes exhibit promising characteristics for light-sensing applications.
- The observed photocurrent behavior suggests potential for novel biosensor development leveraging protein-based materials.
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