Quantum dots as FRET acceptors for highly sensitive multiplexing immunoassays

Daniel Geissler; Niko Hildebrandt; Loïc J. Charbonnière; Raymond F. Ziessel; Hans-Gerd Löhmannsröben

doi:10.1117/12.809444

3 March 2009 Quantum dots as FRET acceptors for highly sensitive multiplexing immunoassays

Daniel Geissler, Niko Hildebrandt, Loïc J. Charbonnière, Raymond F. Ziessel, Hans-Gerd Löhmannsröben

Proceedings Volume 7189, Colloidal Quantum Dots for Biomedical Applications IV; 71890L (2009) https://doi.org/10.1117/12.809444
Event: SPIE BiOS, 2009, San Jose, California, United States

Abstract

Homogeneous immunoassays have the benefit that they do not require any time-consuming separation steps. FRET is one of the most sensitive homogeneous methods used for immunoassays. Due to their extremely strong absorption over a broad wavelength range the use of quantum dots as FRET acceptors allows for large Foerster radii, an important advantage for assays in the 5 to 10 nm distance range. Moreover, because of their size-tunable emission, quantum dots of different sizes can be used with a single donor for the detection of different analytes (multiplexing). As the use of organic dyes with short fluorescence decay times as donors is known to be inefficient with quantum dot acceptors, lanthanide complexes with long luminescence decays are very efficient alternatives. In this contribution we present the application of commercially available biocompatible CdSe/ZnS core/shell quantum dots as multiplexing FRET acceptors together with a single terbium complex as donor in a homogeneous immunoassay system. Foerster radii of 10 nm and FRET efficiencies of 75 % are demonstrated. The high sensitivity of the terbium-toquantum dot FRET assay is shown by sub-100-femtomolar detection limits for two different quantum dots (emitting at 605 and 655 nm) within the same biotin-streptavidin assay. Direct comparison to the FRET immunoassay "gold standard" (FRET from Eu-TBP to APC) yields a three orders of magnitude sensitivity improvement, demonstrating the big advantages of quantum dots not only for multiplexing but also for highly sensitive nanoscale analysis.

Citation Download Citation

Daniel Geissler, Niko Hildebrandt, Loïc J. Charbonnière, Raymond F. Ziessel, and Hans-Gerd Löhmannsröben "Quantum dots as FRET acceptors for highly sensitive multiplexing immunoassays", Proc. SPIE 7189, Colloidal Quantum Dots for Biomedical Applications IV, 71890L (3 March 2009); https://doi.org/10.1117/12.809444

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