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Article CommentaryCommentary

Understanding the Non-Equivalency of Bio-Fluorescent Particle Counts versus the Colony-Forming Unit

Joanny Salvas, Petra Merker, Mike Dingle, Cedric Joossen, Chris Knutsen, David Govezensky, Jim Cannon, Philip Villari, Anthony Cundell, Victoria Navarro, Margit Franz-Riethdorf and Allison Scott
PDA Journal of Pharmaceutical Science and Technology November 2023, 77 (6) 514-518; DOI: https://doi.org/10.5731/pdajpst.2022.012790
Joanny Salvas
1Pfizer, Kirkland, QC, Canada/BioPhorum;
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Petra Merker
2Bayer AG, Müllerstr. 178, D-13353 Berlin, Germany/BioPhorum;
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Mike Dingle
3TSI Incorporated, 500 Cardigan Road, Shoreview, MN 55126 USA/PEMM;
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Cedric Joossen
4Janssen Pharmaceutica NV, Turnhoutseweg 30, 2340 Beerse, Belgium/OWBA;
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Chris Knutsen
5Bristol-Myers Squibb, New Brunswick, NJ, USA/BioPhorum;
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David Govezensky
6Bio-Technology General (Israel) Ltd., POB 571, Be'er Tuvia Industrial Zone, Kiryat Malachi 8310402, Israel/BioPhorum;
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Jim Cannon
7Mettler-Toledo Thornton, Inc., 900 Middlesex Turnpike, Building 8, Billerica, MA 01821/PEMM;
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Philip Villari
8Merck & Co., Inc., Kenilworth, NJ, USA/BioPhorum/PEMM;
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Anthony Cundell
9Microbiological Consulting, LLC., Rye, NY 10580 USA/PEMM;
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Victoria Navarro
10Pfizer, S. S. de los Reyes, Madrid, Spain/BioPhorum;
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Margit Franz-Riethdorf
11BioPhorum Operations Group Limited, 5 Westbrook Court, Sharrowvale Road, Sheffield, S11 8YZ, United Kingdom; and
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  • For correspondence: margit.franz-riethdorf@biophorum.com
Allison Scott
12Azbil North America Research and Development: BioVigilant, 2005 W. Ruthrauff Rd. #151, Tucson, AZ 85705 USA/PEMM
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Abstract

Adopting emerging microbiological methods is often desirable because it enables more advantageous, real-time monitoring practices. However, when the newer method measures contamination based on a different detection principle and provides results that are based on different units of measure, a paradigm shift is necessary. That shift can be one of the most difficult challenges in any such project and requires careful consideration. In this article, we explore the challenges presented by the bio-fluorescent particle counting (BFPC) technology, when considering that the traditional colony-forming unit (CFU) is the gold standard that any change is measured against. We examine why attempts to correlate newer units of measure used by biofluorescent particle counters, namely the auto-fluorescent units (AFUs), to the traditional CFUs are not necessarily appropriate. The article explores in depth why there is no consistent correlation factor between the two units of measure, and why that should not be a barrier to fully leveraging, implementing, and using such modern technologies in routine monitoring.

  • Auto-fluorescence units
  • Alternative and rapid microbial methods
  • Bio-fluorescent particle counters
  • © PDA, Inc. 2023
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PDA Journal of Pharmaceutical Science and Technology: 77 (6)
PDA Journal of Pharmaceutical Science and Technology
Vol. 77, Issue 6
November/December 2023
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Understanding the Non-Equivalency of Bio-Fluorescent Particle Counts versus the Colony-Forming Unit
Joanny Salvas, Petra Merker, Mike Dingle, Cedric Joossen, Chris Knutsen, David Govezensky, Jim Cannon, Philip Villari, Anthony Cundell, Victoria Navarro, Margit Franz-Riethdorf, Allison Scott
PDA Journal of Pharmaceutical Science and Technology Nov 2023, 77 (6) 514-518; DOI: 10.5731/pdajpst.2022.012790

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Understanding the Non-Equivalency of Bio-Fluorescent Particle Counts versus the Colony-Forming Unit
Joanny Salvas, Petra Merker, Mike Dingle, Cedric Joossen, Chris Knutsen, David Govezensky, Jim Cannon, Philip Villari, Anthony Cundell, Victoria Navarro, Margit Franz-Riethdorf, Allison Scott
PDA Journal of Pharmaceutical Science and Technology Nov 2023, 77 (6) 514-518; DOI: 10.5731/pdajpst.2022.012790
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  • Article
    • Abstract
    • Preamble
    • Introduction
    • The Drawbacks of the CFU as a Gold Standard
    • Overview of a Modern Technology That Reports in a Unit Not Equivalent to the CFU
    • Why Are AFUs and CFUs Not Equivalent?
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Keywords

  • Auto-fluorescence units
  • Alternative and Rapid Microbial Methods
  • Bio-fluorescent Particle Counters

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