Waveguide Evanescent Field Scattering Microscopy: Bacterial Biofilms and their Sterilization Response via UV Irradiation

Authors

Qamrun Nahar, Western University
Frederik Fleiβner, Western University
Jeremiah Shuster, Western University
Michael Morawitz, Western University
Christopher Halfpap, Western University
Mihaela Stefan, Trojan Technologies
Uwe Langbein, RheinMain University
Gordon Southam, The University of Queensland
Silvia Mittler, Western UniversityFollow

Document Type

Article

Publication Date

2014

Journal

Journal of Biophotonics

Volume

7

Issue

7

First Page

542

Last Page

551

URL with Digital Object Identifier

https://doi.org/10.1002/jbio.201300135

Abstract

Waveguide Evanescent Field Scattering (WEFS) microscopy is introduced as a new and simple tool for label-free, high contrast imaging of bacteria and bacteria sensors. Bacterial microcolonies and single bacteria were discriminated both by their bright field images and by their evanescent scattering intensity. By comparing bright field images with WEFS images, the proportion of planktonic: sessile (i.e., ‘floating’: attached) bacteria were measured. Bacteria were irradiated with UV light, which limited their biofilm forming capability. A quantitative decrease in attachment of individual, sessile bacteria and in attached, microcolony occupied areas was easily determined within the apparent biofilms with increasing UV dose. WEFS microscopy is an ideal tool for providing rapid quantitative data on biofilm formation.