Abstract

Photoelectrochemical (PEC) DNA sensors are a valuable biotechnology tool that are well suited for early-stage diagnosis of genetic-related diseases.1 Conventional laboratory techniques, such as polymerase chain reaction (PCR), are slow and require additional resources. In contrast, PEC sensors provide a much faster, more accurate, and highly alternative that requires fewer resources.2 Therefore, there is a need for improved PEC sensors that have a higher sensitivity and are much faster than existing sensors.

Researchers at McMaster have discovered a novel PEC DNA biosensor method that uses DNA to create a gap between metal and semiconductor nanoparticles. Notably, this is the first PEC bioassay to use only a single voltage or wavelength of light, making it significantly more sensitive and scalable than existing PEC sensors. The biosensor also has a potential for broader applications, including the sensing of other cellular component sensing using additional bio-recognition agents.

Applications

• DNA detection
• Potential for detecting RNA, proteins, and other cellular components

Advantages

• Higher sensitivity (more than 3x increase)
• Reduced chance for false positive sensing
• Reduced background signal

References

1. Wei, F., Lillehoj, P. & Ho, CM. DNA Diagnostics: Nanotechnology-Enhanced Electrochemical Detection of Nucleic Acids. Pediatr Res 67, 458–468 (2010). https://doi.org/10.1203/PDR.0b013e3181d361c3
2. Devadoss, A., Sudhagar, P., Terashima, C., Nakata, K., & Fujishima, A. (2015). Photoelectrochemical biosensors: New insights into promising photoelectrodes and signal amplification strategies. Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 24, 43-63.

Image obtained from: Saha, S., Victorious, A., Pandey, R., Clifford, A., Zhitomirsky, I., & Soleymani, L. (2020). Differential photoelectrochemical biosensing using DNA nanospacers to modulate electron transfer between metal and semiconductor nanoparticles. ACS applied materials & interfaces, 12(33), 36895-36905.