Localized surface plasmon resonance biosensor using silver nanostructures fabricated by glancing angle deposition.
Glancing angle deposition was used to produce approximately 150-nm-thick silver nanoparticle films, which were evaluated as localized surface plasmon resonance (LSPR) biosensors. The films have a strong extinction peak around 368 nm in air due to LSPR. As the refractive index of the surrounding environment is increased, the extinction peak red-shifts with a linear dependence. The films were functionalized with 11-amino-1-undecanethiol and rabbit immunoglobulin G (rIgG) to allow for the detection of anti-rIgG binding. Binding of biomolecules to the nanoparticle surface increases the local refractive index and results in a red-shifting of the extinction peak. The wavelength shift at varying concentrations of anti-rIgG was measured and fit to the Langmuir isotherm. This yielded approximate values for the saturation response, Delta lambda max = 29.4 +/- 0.7 nm, and the surface confined binding constant, Ka = (2.7 +/- 0.3) x 10(6) M(-1). The response to nonspecific binding was also investigated.
Gish
Douglas A
DA
Department of Electrical and Computer Engineering, University of Alberta, Edmonton, Alberta, Canada. dgish@ualberta.ca
Nsiah
Francis
F
McDermott
Mark T
MT
Brett
Michael J
MJ
D000473:Alkanes / Q000378:metabolism; D000818:Animals; D015374:Biosensing Techniques / Q000379:methods*; D007074:Immunoglobulin G / Q000276:immunology / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008855:Microscopy, Electron, Scanning; D011817:Rabbits; D012834:Silver / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000378:metabolism; D020349:Surface Plasmon Resonance / Q000379:methods*
C510729:11-amino-1-undecanethiol; D000473:Alkanes; D007074:Immunoglobulin G; D013438:Sulfhydryl Compounds; D012834:Silver