Related Experiment Video
Updated: Sep 24, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Two-photon absorption and two-photon-induced isomerization of azobenzene compounds
Marta Dudek1, Nina Tarnowicz-Staniak1, Marco Deiana1
1Advanced Materials Engineering and Modelling Group, Faculty of Chemistry, Wroclaw Unviersity of Science and Technology Wyb. Wyspianskiego 27 50-370 Wroclaw Poland marta.ziemianek-dudek@pwr.edu.pl katarzyna.matczyszyn@pwr.edu.pl.
Abstract:
The process of two-photon-induced isomerization occurring in various organic molecules, among which azobenzene derivatives hold a prominent position, offers a wide range of functionalities, which can be used in both material and life sciences. This review provides a comprehensive description of nonlinear optical (NLO) properties of azobenzene (AB) derivatives whose geometries can be switched through two-photon absorption (TPA). Employing the nonlinear excitation process allows for deeper penetration of light into the tissues and provides opportunities to regulate biological systems in a non-invasive manner. At the same time, the tight focus of the beam needed to induce nonlinear absorption helps to improve the spatial resolution of the photoinduced structures. Since near-infrared (NIR) wavelengths are employed, the lower photon energies compared to usual one-photon excitation (typically, the azobenzene geometry change from trans to cis form requires the use of UV photons) cause less damage to the biological samples. Herein, we present an overview of the strategies for optimizing azobenzene-based photoswitches for efficient two-photon excitation (TPE) and the potential applications of two-photon-induced isomerization of azobenzenes in biological systems: control of ion flow in ion channels or control of drug release, as well as in materials science, to fabricate data storage media, optical filters, diffraction elements etc., based on phenomena like photoinduced anisotropy, mass transport and phase transition. The extant challenges in the field of two-photon switchable azomolecules are discussed.
More Related Videos
Related Concept Videos
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Deactivation Processes: Jablonski Diagram
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
UV–Vis Spectroscopy: Molecular Electronic Transitions
Molecular Spectroscopy: Absorption and Emission
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
