SmartSAST · Non-covalent photoresponsive tags for photoacoustic imaging: Giving voice to living matter

Non-covalent photoresponsive tags for photoacoustic imaging: Giving voice to living matter

For Publication: " Long-Lived Charge-Transfer State from B–N Frustrated Lewis Pairs Enchained in Supramolecular Copolymers" (published Sept 2020) Abstract: The field of supramolecular polymers is rapidly expanding; however, the exploitation of these systems as functional materials is still elusive. To become competitive, supramolecular polymers must display microstructural order and the emergence of new properties upon copolymerization. To tackle this, a greater understanding of the relationship between monomers’ design and polymer microstructure is required as well as a set of functional monomers that efficiently interact with one another to synergistically generate new properties upon copolymerization. Here, we present the first implementation of frustrated Lewis pairs into supramolecular copolymers. Two supramolecular copolymers based on π-conjugated O-bridged triphenylborane and two different triphenylamines display the formation of B–N pairs within the supramolecular chain. The remarkably long lifetime and the circularly polarized nature of the resulting photoluminescence emission highlight the possibility to obtain an intermolecular B–N charge transfer. These results are proposed to be the consequences of the enchainment of B–N frustrated Lewis pairs within 1D supramolecular aggregates. Although it is challenging to obtain a precise molecular picture of the copolymer microstructure, the formation of random blocklike copolymers could be deduced from a combination of optical spectroscopic techniques and theoretical simulation. For publication: "A quantitative model for reversibly photoswitchable sensors" (in revision) Abstract: Composed by a reversibly photoswitchable unit allosterically linked to a sensing module, reversibly photoswitchable sensors (rs-sensors) represent a new and attractive strategy to quantitatively read-out analyte concentrations. However their kinetic response to illumination is complex and much attention is required from the design to the application steps. Here we exploit a generic kinetic model of rs-sensors, which enables us to point on key thermokinetic parameters such as dissociation constants and kinetic rates for exchange towards the analyte, and cross sections for photoswitching. The application of the model allows to evaluate the robustness of the analyzed parameters and to introduce a methodology for their reliable use. Model and methodology have been experimentally tested on a newly reported calcium sensor based on a reversibly photoswitchable green fluorescent protein allosterically linked to a calcium-sensing module integrating calmoduline and a RS20 peptide. Importance for the society: Importance in the field of chemistry, biology, microscopy and biophysics. The work will give a solid support to reliably exploit reversibly photoswitchable sensors Objective within the smartSAST project: Although studied on a different protein-small molecule system, the publication details a theroetical and methodological section aimed to adress the issue of photo-ejection and photo-capture that will be used also to understand and employ the behavior of smartSAST sensors.

Текст от CORDIS, на английски · Данни: CORDIS, © Европейски съюз