Gel Microdroplets: Rapid Detection and Enumeration of Individual Microorganisms by their Metabolic Activity

摘要: We report a new, flexible method for rapid detection and enumeration of individual microorganisms using small (e.g. 10 to 100 micron diameter) gel particles surrounded by non-aqueous liquid with low dielectric constant. Primary samples without prior cultivation can be used. In the present study, microdroplets (GMDs) an inert oil were statistically inoculated such that GMDs had high probability initially containing either zero or one acid-producing microorganism. Such retained dissociable metabolites produced cells (or microcolonies) within GMD volume. The accumulated metabolic acids led changes in pH occupied microorganism colony forming unit (CFU), while unchanged pH. cumulative activity was then determined sensitive fluorescence indicators. This used enumerate cell viability directly, any culture, from clinically infected urine about 1.5 hours several rapidly growing pathogens, agreement much slower conventional culture methods. Because made readily large numbers, because many indicator systems used, automated measurement apparatus should have wide applicability.