Ultrasensitive surface bioaffinity sensors are created by the adsorption of gold nanoparticles onto gold diffraction gratings. An enhanced diffraction obtained in a surface plasmon resonance geometry is observed due to the optical coupling of the planar surface plasmons in the grating to the localized surface plasmons in the gold nanoparticles. As a first example, these nanoparticle grating biosensors are employed to detect unmodified DNA at a concentration of 10 fM.
- bioaffinity sensors
- gold nanoparticles
- diffraction gratings
- unmodified DNA
Wark, A. W., Lee, H. J., Qavi, A. J., & Corn, R. M. (2007). Nanoparticle-enhanced diffraction gratings for ultrasensitive surface plasmon biosensing. Analytical Chemistry, 79(17), 6697-6701. https://doi.org/10.1021/ac071062b