Polymerase chain reaction-gene probe detection of microorganisms by using filter-concentrated samples

To detect low levels of microorganisms in environmental samples by using polymerase chain reaction (PCR)-gene probe detection, samples were concentrated by filtration. Fluoropore (Millipore Corp.) filters were compatible with PCR DNA amplification, whereas various other filters including nitrocellulose and cellulose acetate filters inhibited PCR amplification. By concentrating cells on Fluoropore filters and releasing the DNA by freeze-thaw cycling, PCR DNA amplification could be performed without removing the filter. Concentration with Fluoropore FHLP and FGLP filters permitted the detection of single cells of microorganisms in 100-ml samples by PCR-gene probes.