Challenges Encountered in the Implementation of Bio-Fluorescent Particle Counting Systems as a Routine Microbial Monitoring Tool

PDA J Pharm Sci Technol. 2023 Jan-Feb;77(1):2-9. doi: 10.5731/pdajpst.2021.012726. Epub 2022 Jul 15.


The transition from traditional growth-based microbial detection methods to continuous bio-fluorescent particle counting methods represents a paradigm shift, because the results will be non-equivalent in terms of microbial counts, and a continuous, rather than periodic, data stream will be available. Bio-fluorescent particle counting technology, a type of rapid microbiological method, uses the detection of the intrinsic fluorescence of microbial cells to enumerate bioburden levels in air or water samples, continuously. The reported unit is commonly referred to as an autofluorescence unit, which is not dependent upon growth, as is the traditional method. The following article discusses challenges encountered when implementing this modern technology, and the perspective from a consortium of four industry working groups on navigating these challenges.

Keywords: Autofluorescence unit (AFU); Bio-fluorescent particle counting (BFPC); Environmental monitoring (EM); Modern microbiological method process analytical technology (PAT); Rapid microbiological method (RMM); Water monitoring.

MeSH terms

  • Coloring Agents*
  • Environmental Monitoring / methods
  • Fluorescence
  • Technology*


  • Coloring Agents