Related Experiment Video
Updated: Jun 23, 2026

Polarization-Sensitive Two-Photon Microscopy for a Label-Free Amyloid Structural Characterization
Published on: September 8, 2023
Polarization portraits of single multichromophoric systems: visualizing conformation and energy transfer
Oleg Mirzov1, Robbert Bloem, Peter Ralph Hania
1Chemical Physics, Lund University, P.O. Box 124, 22100 Lund, Sweden.
Abstract:
A novel technique, two-dimensional (2D) polarization single-molecule imaging, is presented. It is based on measurements and analysis of fluorescence intensity as a function of excitation and emission polarization angles. The technique allows recording of full information on the steady-state polarization properties of fluorescent objects. It is particularly suitable for application to single multichromophoric systems (molecules or nanoparticles) with energy transfer (ET) between different chromophores (e.g., single fluorescent pi-conjugated polymer chains). The 2D polarization data simultaneously provide information on the conformation of the system and the efficiency of its internal excitation ET. The technique is used to characterize single chains and different kinds of chain aggregates of different conjugated polymers at different temperatures. The 2D polarization measurements reveal a dramatic difference in ET taking place in these systems. Clear temperature dependence of ET is observed for individual aggregates as well as for their statistical ensembles. Also, a dependence on solvent and aggregate size is shown. Additionally, extensive "traditional one-dimensional" polarization results on the polarization anisotropy of fluorescence excitation and emission are presented. These results and findings are discussed in relation to internal organization of the nano-objects under study.
Related Concept Videos
Group Polarization
UV–Vis Spectroscopy of Conjugated Systems
One of the factors influencing λmax is the extent of conjugation in the...
Photochemical Electrocyclic Reactions: Stereochemistry
Selection Rules: Photochemical Activation
Potential Due to a Polarized Object
Energy Diagrams, Transition States, and Intermediates
Energy Diagrams - II
The point in the energy diagram at which the system’s potential energy is the lowest is known as the local minima. The system tends to stay in this position indefinitely unless acted upon by a net force. The slope of the potential energy diagram at the local minima is zero, indicating that zero net force is acting on the system. The slope...
