Planarizable push-pull probes : overtwisted flipper mechanophores

Macchione, Mariano; Chuard, Nicolas; Sakai, Naomi; Matile, Stefan

doi:10.1002/cplu.201600634

Scientific article

English

Planarizable push-pull probes : overtwisted flipper mechanophores

Contributors

Macchione, Mariano; Chuard, Nicolas; Sakai, Naomi

; Matile, Stefan

Published in

ChemPlusChem, vol. 82, no. 7, p. 1062-1066

Publication date

2017

Abstract

Planarizable push–pull fluorescent probes, also referred to as flipper probes, have been introduced as conceptually innovative mechanophores that report on forces in their local environment in lipid bilayer membranes. The best flipper probes respond to a change from liquid disordered to solid ordered membranes with a red shift in excitation of 50–90 nm. A simultaneous increase in fluorescence lifetime and negligible background fluorescence from the aqueous phase qualifies these fluorescent probes for meaningful imaging in live cells. Here, we report that the replacement of methyl with isobutyl substituents along the scaffold of a dithienothiophene dimer strongly reduces fluorescence intensity but increases solvatochromism slightly. These trends imply that the large substituents in “leucine flippers” hinder the planarization in the first excited state to result in twisted intramolecular charge transfer (TICT). As a result of this overtwisting, the leucine flippers form interesting fluorescent micelles in water but fail to respond to changes in membrane order. These dramatic changes in function provide one of the most impressive illustrations for the hypersensitivity of fluorescent membrane probes toward small changes in their structure.

Keywords

Conformation analysis
Fluorescent probes
Membranes
Mechanophores
Push–pull chromophores

UNIGE affiliation entities

Faculté des sciences / Section de chimie et biochimie / Département de chimie organique

UNIGE research groups

Groupe Matile

Citation (ISO format)

MACCHIONE, Mariano et al. Planarizable push-pull probes : overtwisted flipper mechanophores. In: ChemPlusChem, 2017, vol. 82, n° 7, p. 1062–1066. doi: 10.1002/cplu.201600634

Article (Published version)

Article (Accepted version)

Identifiers

PID : unige:95494
DOI : 10.1002/cplu.201600634

Journal ISSN

2192-6506

664views

577downloads

Creation

18/07/2017 11:12:00

First validation

18/07/2017 11:12:00

Update

13/10/2025 19:55:34

Status update

15/03/2023 01:50:03

Last indexation

16/02/2026 06:57:51

Planarizable push-pull probes : overtwisted flipper mechanophores

Contributors

Published in

Publication date

Abstract

Keywords

UNIGE affiliation entities

UNIGE research groups

Citation (ISO format)

Main files (2)

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Journal ISSN

Technical informations

Creation

First validation

Update

Status update

Last indexation