On-demand COMmunication between fluorescent organic nanoparticles through Energy Transfer

Introduction

In situ and real-time detection of analytes in complex biological media requires the development of robust and sensitive biosensors. In this context, the interdisciplinary COMET project will develop innovative optical biosensors based on communicating nanoparticles (NPs) whose response is modulated by the presence of opioids.

Current Challenges

To date, robust inter-particle communication between optically-active NPs has only been described with inorganics, involving either electron or resonance energy transfer. Despite their excellent optical properties, inorganic NPs raise environmental and biocompatibility concerns with respect to their toxicity or colloidal stability.

Alternative Solutions

In that regard, Fluorescent Organic Nanoparticles (FONs) are an interesting alternative:

• FONs are composed of organic dyes condensed in a small volume.
• They are engineered to display intense absorption and excellent brightness.

The optimal arrangement of spectrally complementary FONs acting as synergistic energy donors and acceptors will address the critical challenge of achieving communication between NPs and signal amplification.

Project Goals

To meet this goal, COMET will reinvent the classical FONs elaboration by investigating the self-assembly of dedicated dyes concomitantly with a biological recognition moiety in water.

Methodology

Spectrally relevant FONs will be associated into nano-constructions in which a donor and an acceptor FON are brought together to enable energy transfer.

I will then design stimuli-responsive biosensors based on the triggered disruption of these nano-assemblies by an analyte, particularly opioids. The detection of nanomolar traces of opioids will be achieved thanks to signal amplification through cascade energy transfers within and between FONs.

Impact

Such communicating nano-tools will provide the next generation of continuous ratiometric biosensors. In addition, they will open the way to a new paradigm in excitation energy migration and impact other research fields such as optoelectronics and nanomedicine.