Waveguide-excited fluorescence microarray

Gabriel Sagarzazu; Mélanie Bedu; Lucio Martinelli; Khoi-Nguyen Ha; Nicolas Pelletier; Viatcheslav I. Safarov; Claude Weisbuch; Thierry Gacoin; Henri Benisty

doi:10.1117/12.781297

2 May 2008 Waveguide-excited fluorescence microarray

Gabriel Sagarzazu, Mélanie Bedu, Lucio Martinelli, Khoi-Nguyen Ha, Nicolas Pelletier, Viatcheslav I. Safarov, Claude Weisbuch, Thierry Gacoin, Henri Benisty

Author Affiliations +

Proceedings Volume 6991, Biophotonics: Photonic Solutions for Better Health Care; 699123 (2008) https://doi.org/10.1117/12.781297
Event: SPIE Photonics Europe, 2008, Strasbourg, France

Abstract

Signal-to-noise ratio is a crucial issue in microarray fluorescence read-out. Several strategies are proposed for its improvement. First, light collection in conventional microarrays scanners is quite limited. It was recently shown that almost full collection can be achieved in an integrated lens-free biosensor, with labelled species hybridizing practically on the surface of a sensitive silicon detector [L. Martinelli et al. Appl. Phys. Lett. 91, 083901 (2007)]. However, even with such an improvement, the ultimate goal of real-time measurements during hybridization is challenging: the detector is dazzled by the large fluorescence of labelled species in the solution. In the present paper we show that this unwanted signal can effectively be reduced if the excitation light is confined in a waveguide. Moreover, the concentration of excitation light in a waveguide results in a huge signal gain. In our experiment we realized a structure consisting of a high index sol-gel waveguide deposited on a low-index substrate. The fluorescent molecules deposited on the surface of the waveguide were excited by the evanescent part of a wave travelling in the guide. The comparison with free-space excitation schemes confirms a huge gain (by several orders of magnitude) in favour of waveguide-based excitation. An optical guide deposited onto an integrated biosensor thus combines both advantages of ideal light collection and enhanced surface localized excitation without compromising the imaging properties. Modelling predicts a negligible penalty from spatial cross-talk in practical applications. We believe that such a system would bring microarrays to hitherto unattained sensitivities.

Citation Download Citation

Gabriel Sagarzazu, Mélanie Bedu, Lucio Martinelli, Khoi-Nguyen Ha, Nicolas Pelletier, Viatcheslav I. Safarov, Claude Weisbuch, Thierry Gacoin, and Henri Benisty "Waveguide-excited fluorescence microarray", Proc. SPIE 6991, Biophotonics: Photonic Solutions for Better Health Care, 699123 (2 May 2008); https://doi.org/10.1117/12.781297

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
8 PAGES

DOWNLOAD PAPER SAVE TO MY LIBRARY

GET CITATION

RIGHTS & PERMISSIONS

Get copyright permission Get copyright permission on Copyright Marketplace

KEYWORDS

Waveguides

Luminescence

Biosensors

Sensors

Charge-coupled devices

CCD image sensors

Image filtering

Show All Keywords

Keywords/Phrases

Search In:

Publication Years