Abstract
While colloidal quantum dots (QDs) are commonly used as fluorescent donors within biosensors based on Förster resonant energy transfer (FRET), they are hesitantly employed as acceptors. On the sole basis of Förster theory and the well-known behaviour of organic dyes, it is often argued that the QD absorption band over the UV-visible range is too wide. Discarding these preconceptions inherited from classical fluorophores, we experimentally examine the FRET process occurring between donor and acceptor CdTe QDs and provide a mathematical description of it. We evidence that the specific features of QDs unexpectedly lead to the enhancement of acceptors' emission (up to +400%), and are thus suitable for the design of highly efficient all-QD based FRET sensors. Our model enables us to identify the critical parameters maximizing the contrast between positive and negative biosensing readouts: the concentrations of donors and acceptors, their spectral overlap, the densities of their excitonic states, their dissipative coupling with the medium and the statistics of QD-QD chemical pairing emerge as subtle and determinant parameters. We relate them quantitatively to the measured QD-QD FRET efficiency and discuss how they must be optimized for biosensing applications.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.