Improved direct epifluorescent filter technique for rapid bioburden control in intravenous solutions

Epifluorescence microscopy of the microcolonies obtained after filtration of a deliberately contaminated intravenous solution, was used for the rapid detection and enumeration of the bacteria. The technique is adequate for the test of low volume solution (with low contamination). Also it allows one to detect a single colony forming unit (c.f.u.)/mL, with great correlation between fluorescence counts and pour plate colony counts; the morphology of microcolonies is typical for most of the microorganisms and it allows a primoidentification (for a trained analyst).