Fiber-optic sample illuminator design for the observation of light induced phenomena with transmission electron microscopy in situ: Antimicrobial photodynamic therapy

Andrzej M Żak; Olga Kaczmarczyk; Marta Piksa; Jakub Grzęda; Katarzyna Matczyszyn

doi:10.1016/j.ultramic.2021.113388

Fiber-optic sample illuminator design for the observation of light induced phenomena with transmission electron microscopy in situ: Antimicrobial photodynamic therapy

Ultramicroscopy. 2021 Nov:230:113388. doi: 10.1016/j.ultramic.2021.113388. Epub 2021 Sep 4.

Authors

Andrzej M Żak¹, Olga Kaczmarczyk², Marta Piksa³, Jakub Grzęda⁴, Katarzyna Matczyszyn⁵

Affiliations

¹ Electron Microscopy Laboratory, Faculty of Mechanical Engineering, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland; Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Rudolfa Weigla 12, 53-114 Wroclaw, Poland. Electronic address: andrzej.zak@pwr.edu.pl.
² Electron Microscopy Laboratory, Faculty of Mechanical Engineering, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
³ Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Rudolfa Weigla 12, 53-114 Wroclaw, Poland.
⁴ Department of Lightweight Elements Engineering, Foundry and Automation, Faculty of Mechanical Engineering, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.
⁵ Advanced Materials Engineering and Modelling Group, Faculty of Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370 Wrocław, Poland.

PMID: 34509894
DOI: 10.1016/j.ultramic.2021.113388

Abstract

Antibacterial photodynamic therapy is a promising treatment for problematic infections caused by bacteria and fungi. Despite its undoubted effectiveness, the ultrastructural mechanism of microbial death remains not fully described and distinct organisms respond to the treatment with different efficacy. For this reason, it was decided to try imaging the process using the in situ transmission electron microscopy method. To conduct an observational experiment, the microscope was significantly modified. Liquid cell methods were used, electron doses and their influence on the sample were estimated, and a fiber-optic sample illuminator was designed and built. The modifications allowed for the light-induced characterization of photosensitizer-bacteria interaction. Microscope modification is a promising platform for further studies of light-induced phenomena in both life and material science.

Keywords: In situ TEM; In-situ; Laser; Methylene blue; Photochemical reaction; aPDT.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Anti-Bacterial Agents / pharmacology
Anti-Infective Agents*
Microscopy, Electron, Transmission
Photochemotherapy* / methods
Photosensitizing Agents / pharmacology

Substances

Anti-Bacterial Agents
Anti-Infective Agents
Photosensitizing Agents