AAC
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Hope, C. K.
Right arrow Articles by Wilson, M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hope, C. K.
Right arrow Articles by Wilson, M.

 Previous Article  |  Next Article 

Antimicrobial Agents and Chemotherapy, May 2004, p. 1461-1468, Vol. 48, No. 5
0066-4804/04/$08.00+0     DOI: 10.1128/AAC.48.5.1461-1468.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.

Analysis of the Effects of Chlorhexidine on Oral Biofilm Vitality and Structure Based on Viability Profiling and an Indicator of Membrane Integrity

C. K. Hope and M. Wilson*

Microbiology Unit, Division of Infection and Immunity, Eastman Dental Institute for Oral Health Care Sciences, University College London, London, United Kingdom

Received 21 October 2003/ Returned for modification 7 November 2003/ Accepted 8 January 2004

Multispecies biofilms modeling interproximal plaque were grown on a hydroxyapatite substratum in a constant-depth film fermentor and then immersed in a viewing solution containing fluorescent indicators of membrane integrity. Confocal laser scanning microscopy (CLSM) revealed the structure and spatial distribution of cell vitality within the biofilms. Chlorhexidine gluconate (CHX) was added to the viewing solution to achieve concentrations of 0.05 and 0.2% (wt/vol) before further CLSM time-lapse series were captured. Image analysis showed that exposure to 0.2% CHX caused the biofilm to contract at a rate of 1.176 µm min–1 along the z axis and also effected changes in total fluorescence measurements and viability profiles through the biofilms after a delay of 3 to 5 min. At a concentration of 0.05% CHX, total fluorescence measurements for the biofilm exhibited barely detectable changes after 5 min. Fluorescence profiles (fluorescence versus time versus depth), however, clearly showed that a time-dependent effect was present, but the clearest indicator of the effect of dilute CHX over time was viability profiling. These findings suggest the possibility of using fluorescent indicators of membrane integrity in conjunction with viability profiling to evaluate the penetration of the bactericidal effects of membrane-active antimicrobial compounds into biofilm.

* Corresponding author. Mailing address: Microbiology Unit, Eastman Dental Institute for Oral Health Care Sciences, University College London, 256 Gray's Inn Rd., London WC1X 8LD, United Kingdom. Phone: 44 (0)207 915 1050. Fax: 44 (0)207 915 1127. E-mail: m.wilson{at}eastman.ucl.ac.uk.

Antimicrobial Agents and Chemotherapy, May 2004, p. 1461-1468, Vol. 48, No. 5
0066-4804/04/$08.00+0     DOI: 10.1128/AAC.48.5.1461-1468.2004
Copyright © 2004, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Clin. Vaccine Immunol. Clin. Microbiol. Rev.
J. Clin. Microbiol. ALL ASM JOURNALS

Copyright © 2004 by the American Society for Microbiology. All rights reserved.