Engineering plasmonic nanomaterials or nanostructures towards ultrasensitive biosensing for disease markers or pathogens is of high importance. Here we demonstrate a systematic approach to tailor effective plasmonic nanorod arrays by combining both comprehensive numerical discrete dipole approximations (DDA) simulation and transmission spectroscopy experiments. The results indicate that 200×50 nm nanorod arrays with 300×500 nm period provide the highest FOM of 2.4 and a sensitivity of 310 nm/RIU. Furthermore, we demonstrate the use of nanorod arrays for the detection of single nucleotide polymorphism in codon 12 of the K-ras gene that are frequently occurring in early stages of colon cancer, with a sensitivity down to 10 nM in the presence of 100-fold higher concentration of the homozygous genotypes. Our work shows significant potential of nanorod arrays towards point-of-care applications in diagnosis and clinical studies.
- nanorod array
- localized surface plasmon resonance
- discrete dipole approximation
- single nucleotide polymorphism
Dodson, S. L., Cao, C., Zaribafzadeh, H., Li, S., & Xiong, Q. (2015). Engineering plasmonic nanorod arrays for colon cancer marker detection. Biosensors and Bioelectronics, 63, 472-477. https://doi.org/10.1016/j.bios.2014.07.083