Gábor Steinbach1, Gábor Sipka2, István Pomozi3, Győző Garab2 (1Institute of Biophisics,
BRC HAS, Szeged, Hungary; 2Institute of Plant Biology, BRC HAS, Szeged, Hungary;
3Drem Ltd., Budapest, Hungary): Biological Applications of Differencialpolarization
Laserscanning Microscopy (DP-LSM) / Biológiai alkalmazások differenciálpolarizációs
lézerpésztázó mikroszkópra (DP-LSM)
Most biological samples contain organized, complex molecular structures, but these cannot be
explored with conventional optical microscopy. The differential-polarization technique (DPLSM) developed in the Biological Research Centre, Szeged unites confocal microscopy with
a dichrograph providing the image quality and resolution of the LSM and the structural
molecular information of the dichrographs. The high frequency modulation of the polarized
light and synchronized demodulation of the measured intensities provides the DP values –
linear (LD) and circular dichroism (CD), anisotropy of the fluorescence emission upon nonpolarized excitation (r) and circularly polarized luminescence (CPL), fluorescence detected
linear and circular dichroism (FDLD and FDCD), the degree of polarization of the
fluorescence emission (P), and linear birefringence (LB) – pixel-by-pixel.
The DP-LSM is suitable for structural measurements on fixes or living samples. The
presented applications cover DP measurements on cellulose filaments, stacked thylakoid
membranes, amyloids, self-assembly aggregates and lipid rafts. The DP measurements
provided unique information about the molecular organization.
The original DP-LSM setup was developed for a Zeiss LSM410. The scheme after some
modification was suitable for an Olympus FV500 as well having a separated scan-head, and
now a Nikon C1 confocal is under progress.
The DP extension can be attached to LSMs essentially without changing its optical and
electronic units – the proper connection conditions have to be set. The LSMs with DP
attachments are suitable for obtaining unique structural information on the anisotropic
molecular organization of biological samples and intelligent materials in 2D and 3D.
Fluorescence-detected linear dichroism (FDLD) images of Picea omorika section /
Fluorescencia-detektált lineáris dikroizmus (FDLD) leképezés Picea omorika (szerb luc)
metszeten
Savic et al. Microsc. Microanal. 22, 361–367, 2016