Evanescent wave fluorescence biosensors: Advances of the last decade

Abstract

Biosensor development has been a highly dynamic field of research and has progressed rapidly over the past two decades. The advances have accompanied the breakthroughs in molecular biology, nanomaterial sciences, and most importantly computers and electronics. The subfield of evanescent wave fluorescence biosensors has also matured dramatically during this time. Fundamentally, this review builds on our earlier 2005 review. While a brief mention of seminal early work will be included, this current review will focus on new technological developments as well as technology commercialized in just the last decade. Evanescent wave biosensors have found a wide array applications ranging from clinical diagnostics to biodefense to food testing; advances in those applications and more are described herein.

Keywords: Applications; Evanescent wave; Fluorescence; Optical biosensor.

Figure 1

Fiber probe waveguide and biosensing scheme used in the BioHawk (Saaski 2009). Reprinted with permission from SPIE and the author.

Figure 2

Integrating waveguide capillary sensor (Baldini et al. 2008). Schematics a and b diagram the waveguide and channel from the side and end, respectively, while a photo of a 4-channel device is shown on the right. Reprinted with permission from IEEE.

Figure 3

Planar waveguide biosensors for fluorescence detection in the evanescent region: NRL system (left) and mBio (right).

Figure 4

Biosensing with ring resonators (Kindt and Bailey 2013). Reprinted with permission from Elsevier.

Figure 5

Zero mode waveguides (Levene et al. 2003) Left: Simulation of the log of the intensity distribution for a zero-mode waveguide 50 nm in diameter and 100 nm long. Right: The effective volume V_eff and the corresponding concentration for which an average of one molecule enters the volume. Reprinted with permission from Science.