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How to release the bacterial cells from filter paper? - (May/27/2014 )

Dear all, 


I filtered my bacterial sample using vacuum filtration system. May I know is there any method can fully release out the bacterial that retain on the filter paper? Because I am going to proceed into next step which need to incubate the dried bacterial cells into nutrient broth.


Thank you. 



why do you need to the whole bacteria for inoculation to NB? I had an experiment with filteration just for weighting the dried bacteria, but if you realy need to inoculate whole, I think you can put the paper in the broth flask or wash it in a sterile condition by a sterile pincer in the broth.


Why not place the entire  filter in the nutrient medium?

-Phil Geis-

Thanks for the suggestion. But do you think if I place/wash the filter paper in the nutrient medium will still have some remaining on the paper? Besides that, I was using pore size 0.45um to filter the bacteria culture, however I was noticed that the eluate contains the bacteria as well? Why does it happened? I thought filter paper 0.45um will retain all the bacterial cells? Thank you. 


Standard bacterial filtration requires 0.20 or 0.22um, unless you are working with really big and/or filamentous guys that cause fast clogging of filters. In any case, with a fibrous material like filter paper will have a lot of bugs between the fibres. Most filtration membranes have a porous and/or fibrous surface, probably the only ones that are not like that are the Isopore filters, but they have a very limited filtration capacity due this. They are use for epifluorescence.

-El Crazy Xabi-