This paper addresses the optimization of prism-coupled, wavelength-interrogated surface-plasmon resonance (SPR) sensors. Limit of detection (LOD), rather than sensitivity, is chosen as a figure of merit. The Cramer-Rao bound (CRB) for spectral shift estimation allows lower bounds to be placed on LOD independent of interrogation system and estimation algorithm. Analytic evaluation of the CRB for a Lorentzian spectral feature justifies common observations about the relationship between resonance line shape and sensor performance. Numerical evaluation of standard SPR sensor configurations shows that maximizing sensitivity is an insufficient criterion for minimizing limit of detection. Designs optimized for LOD are presented for common SPR sensor materials and geometries.
|Number of pages||6|
|Journal||IEEE Sensors Journal|
|State||Published - Feb 2008|
Bibliographical noteFunding Information:
Manuscript received April 10, 2007; revised October 9, 2007; accepted October 9, 2007. This work was supported in part by the National Science Foundation under Grant 0716486. Facilities and technical assistance for this work were provided by the University of Kentucky Center for Nanoscale Science and Engineering (CeNSE) which is supported in part by the National Science Foundation EPSCoR under Grant 0447479. The associate editor coordinating the review of this paper and approving it for publication was Prof. Ignacio Matias.
- Biochemical sensing
- Optical sensing
- Spectral analysis
- Surface plasmons
ASJC Scopus subject areas
- Electrical and Electronic Engineering