This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplemental material
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 Google Scholar
Google Scholar
Right arrow Articles by Yung, P. T.
Right arrow Articles by Ponce, A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Yung, P. T.
Right arrow Articles by Ponce, A.
Agricola
Right arrow Articles by Yung, P. T.
Right arrow Articles by Ponce, A.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, December 2008, p. 7669-7674, Vol. 74, No. 24
0099-2240/08/$08.00+0     doi:10.1128/AEM.01437-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Fast Sterility Assessment by Germinable-Endospore Biodosimetry{triangledown} ,{dagger}

Pun To Yung and Adrian Ponce*

California Institute of Technology, Jet Propulsion Laboratory, Pasadena, California

Received 27 June 2008/ Accepted 16 September 2008

The increased demand for sterile products has created the need for rapid technologies capable of validating the hygiene of industrial production processes. Bacillus endospores are in standard use as biological indicators for evaluating the effectiveness of sterilization processes. Currently, culture-based methods, requiring more than 2 days before results become available, are employed to verify endospore inactivation. We describe a rapid, microscopy-based endospore viability assay (µEVA) capable of enumerating germinable endospores in less than 15 min. µEVA employs time-gated luminescence microscopy to enumerate single germinable endospores via terbium-dipicolinate (Tb-DPA) luminescence, which is triggered under UV excitation as 108 DPA molecules are released during germination on agarose containing Tb3+ and a germinant (e.g., L-alanine). Inactivation of endospore populations to sterility was monitored with µEVA as a function of thermal and UV dosage. A comparison of culturing results yielded nearly identical decimal reduction values, thus validating µEVA as a rapid biodosimetry method for monitoring sterilization processes. The simple Tb-DPA chemical test for germinability is envisioned to enable fully automated instrumentation for in-line monitoring of hygiene in industrial production processes.

* Corresponding author. Mailing address: California Institute of Technology, Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109. Phone: (818) 354-8196. Fax: (818) 393-4445. E-mail: adrian.ponce{at}jpl.nasa.gov

{triangledown} Published ahead of print on 3 October 2008.

{dagger} Supplemental material for this article may be found at http://aem.asm.org/.

Applied and Environmental Microbiology, December 2008, p. 7669-7674, Vol. 74, No. 24
0099-2240/08/$08.00+0     doi:10.1128/AEM.01437-08
Copyright © 2008, American Society for Microbiology. All Rights Reserved.





Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»