Induction of lethal photosensitization in biofilms using a confocal scanning laser as the excitation source.

Abstract

OBJECTIVES:

To induce lethal photosensitization in biofilms of Streptococcus pyogenes using the scanning laser in a confocal microscope to photoactivate Sn (IV) chlorin e6 (SnCe6) while simultaneously measuring changes in cell vitality using fluorescent indicators of membrane integrity.

METHODS:

Biofilms of S. pyogenes were immersed in a solution of 50 mg/L (70.28 microM) SnCe6 and scanned with the 488 nm argon and 543 nm HeNe lasers in a confocal microscope. Changes in membrane permeability were quantified using image analysis tools.

RESULTS:

Cell permeability increased in biofilms of S. pyogenes after successive scanning/exposure cycles in the presence of SnCe6.

CONCLUSIONS:

Cell death was induced in biofilms of S. pyogenes by the photosensitizer SnCe6 on exposure to the scanning laser emissions of a confocal microscope. The simultaneous recording of cell death demonstrates the real-time evaluation of a light-activated antimicrobial compound against a biofilm.

• Authors: C K Hope, M Wilson
• Journal: The Journal of antimicrobial chemotherapy (J Antimicrob Chemother) Vol. 57 Issue 6 Pg. 1227-30 (Jun 2006) ISSN: 0305-7453 [Print] England
• PMID: 16549510 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Anti-Bacterial Agents
• Fluorescent Dyes
• Metalloporphyrins
• Photosensitizing Agents
• tin(IV) chlorin e6

Topics

• Anti-Bacterial Agents (pharmacology)
• Biofilms (drug effects, growth & development)
• Cell Membrane (pathology)
• Cell Membrane Permeability (physiology)
• Fluorescent Dyes (metabolism)
• Image Processing, Computer-Assisted
• Lasers
• Metalloporphyrins (pharmacology)
• Photosensitizing Agents (pharmacology)
• Streptococcus pyogenes (drug effects, growth & development)