Abstract
The influence of colloid diameter on the surface plasmon resonance (SPR) response of a colloidal Au modified Au film is described. Adsorption of 30-59 nm diameter colloidal Au on the surface of a 47 nm thick Au film results in dramatic, size-dependent shifts in plasmon angle, minimum reflectance, and curve breadth. Each of these parameters is observed to increase with particle diameter and particle coverage, eventually reaching a plateau when the attenuation of the SPR curve is maximized. The angle of maximum change in reflectance is observed to be independent of particle size; thus, the reflectance at that angle is proposed as a method for quantifying the perturbation induced by a particular size and coverage of colloidal Au. These results are discussed in terms of the detection limits and dynamic range of colloidal Au-amplified SPR biosensing.
| Original language | English |
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| Pages (from-to) | 5826-5831 |
| Number of pages | 6 |
| Journal | Journal of Physical Chemistry B |
| Volume | 103 |
| Issue number | 28 |
| DOIs | |
| State | Published - 15 Jul 1999 |
| Externally published | Yes |