Controlling the Fluorescence Properties of Diarylethene-based Photochromic Systems
Doctoral thesis, 2022

Diarylethene (DAE) photoswitches are one of the most promising families of photochromic molecules because of their outstanding photophysical/photochemical properties. This class of compounds, which can photoisomerize between an open colorless and a closed colored form, has been applied in various fields in this thesis work, spanning one-color fluorescence intensity modulation, all-photonic full-color reproduction, light-induced color changes for molecular logic gates and information processing. Particularly, all systems presented can be all-photonically controlled, which is extremely beneficial as light is a sustainable resource from nature that is non-invasive, clean, and waste free that also allows for remote operation.
The first part of the thesis deals with introducing the light-induced isomerization process of the diarylethene derivatives. Through the isomerization of DAEs, intrinsic one-color “on-off” fluorescent intensity modulation as well as dynamic multicolor changes can be realized in the designed systems. In paper I, the diarylethene derivative Dasy is applied as a fluorescent probe aiming at phase-sensitive (lock-in) detection for high-contrast cell studies using fluorescence microscopy. The rapid switching fluorescence signal of Dasy can be successfully discriminated from strong fluorescence background using amplitude modulated red light. In paper II, a photoswitch cocktail mixture is designed where the color of the system can be tuned dynamically only by light-controlled isomerizations of the two monomer photoswitches.
The second part of the thesis focuses on discussing Förster Resonance Energy Transfer (FRET) based photoswitching systems where the emission is controlled through FRET processes by harnessing the different absorption and emission properties of the open and closed isomers of the DAE derivatives. In paper III, the FRET process can be orthogonally controlled by selective isomerization of two individual DAE acceptors, which results in an all-photonic full color red-green-blue (RGB) emissive system. In paper IV, a photoswitch triad is used as a sequential molecular logic gate where the emission output can be controlled by two mechanisms, both inherent and FRET controlled intensity change.

isomerization

color change

photochromic molecules

molecular logic

intensity modulation

diarylethene

RGB

all-photonic

FRET

KC-salen, Kemigården 4
Opponent: professor Jean-Luc Pozzo, University of Bordeaux, France

Author

Gaowa Naren

Chalmers, Chemistry and Chemical Engineering, Chemistry and Biochemistry

A simplicity-guided cocktail approach toward multicolor fluorescent systems

Chemical Communications,; Vol. 56(2020)p. 3377-3380

Journal article

An all-photonic full color RGB system based on molecular photoswitches

Nature Communications,; Vol. 10(2019)

Journal article

One-Time Password Generation and Two-Factor Authentication Using Molecules and Light

ChemPhysChem,; Vol. 18(2017)p. 1726-1729

Journal article

The thesis focuses on developing different diarylethene (DAE) based photochromic systems that can be all-optically controlled. Diarylethene is a type of photochromic molecule that can undergo reversible color and structural changes through light irradiation. In addition to the color and the structural changes, many other properties also change upon isomerization. In principle, a good rule is to assume that almost every molecular property is altered upon isomerization. Thanks to those differences between the two isomers, photochromic molecules are intensively studied and applied in various research fields, such as photopharmacology, bioimaging, super‐resolution fluorescence microscopy, and information storage. Moreover, photochromic products such as ophthalmic lenses, security inks, textiles, and cosmetics are also commonly seen in our daily life.

The emission color of the presented systems can be either tuned dynamically or switched between “on” and “off” states. The work has potential to be applied in various areas, such as fluorescence microscopy, molecular logic, multi-color and full color reproduction. In addition, all systems are driven by light, which is a sustainable resource from nature that has not been efficiently applied as an energy input. The all-photonic nature lets the designed systems become non-invasive and waste free, at the same time responding remotely and instantaneously.

Driving Forces

Sustainable development

Innovation and entrepreneurship

Areas of Advance

Nanoscience and Nanotechnology (SO 2010-2017, EI 2018-)

Subject Categories

Physical Sciences

Chemical Sciences

Roots

Basic sciences

Learning and teaching

Pedagogical work

ISBN

978-91-7905-626-1

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5092

Publisher

Chalmers

KC-salen, Kemigården 4

Opponent: professor Jean-Luc Pozzo, University of Bordeaux, France

More information

Latest update

6/30/2022