Long-wavelength infrared sensing by cytochrome C protein thin film deposited by the spin coating method

• Published in: Sensors (Basel, Switzerland) Vol. 13; no. 11; pp. 15833 - 15845
• Main Authors: Lai, Bo-Yu, Chu, Chung-Hao, Su, Guo-Dung John
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 20-11-2013; Molecular Diversity Preservation International (MDPI)
• Subjects: Biosensing Techniques - methods; bolometer; Breath tests; Cadmium telluride; Cytochrome; cytochrome c protein; Cytochromes c - chemistry; Fourier transforms; Hydrophilic surfaces; Infrared radiation; Infrared Rays; long-wavelength infrared; Membranes, Artificial; Molecular structure; Proteins; Sensors; Temperature; temperature coefficient of resistance; Thin films
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s131115833

High infrared absorption, large temperature coefficient of resistance (TCR) and small 1/f noise are preferred characteristics for sensing materials used in bolometers. In this paper, we discuss a cytochrome c protein as a potential sensing material for long-wavelength bolometers. We simulated and experimentally proved high infrared absorption of cytochrome c in the wavelength between 8 μm and 14 μm. Cytochrome c thin films were deposited on a hydrophilic surface using the spin coating method. The resistance variation with temperature is measured and we show that the TCR of cytochrome c thin films is consistently higher than 20%. The measured values of 1/f noise were as low as 2.33 × 10⁻¹³ V²/Hz at 60 Hz. Finally, we test the reliability of cytochrome c by measuring the resistance changes over time under varying conditions. We found that cytochrome c thin films deteriorated significantly without appropriate packaging.