plate in a sterile petri dish for microbial contaminant culturing. Detailed
described in Millipore publications dealing with specific applications.
analytical procedures are
This filter holder may not be autoclave with a filter in place. For bacteriological analyses, separately
sterilize the holder with dry heat or by autoclaving the disassembled funnel and base for 15-20 minutes at
121°C (15 psig), then reassemble it aseptically with a sterile Millipore filter.
In sterilizing or autoclaving, the funnel and base should first be wrapped with lint-free Kraft paper or
Tyvek, then secured with tape to close the openings and protect the filter support area. Since
temperatures are known to vary from point to point in an autoclave, and may differ significantly from the
autoclave setting, they should be checked occasionally with a maximum registering thermometer.
Avoid using autoclave steam containing amines, which are often added to boiler feed water to prevent
scale. They may contaminate liquids that come in contact with autoclave surfaces.
Procedure for Flammable Liquids
When flammable liquids are filtered through a membrane, high static
charges may be generated. The possibility of a fire, or explosion that might
ensue from this static electricity, can be prevented by grounding the filter
holder in the manner explained below.
A Hydrosol Grounding Lead (Fig. 5) is contained with your Millipore Hydrosol Holder. It consists of a
length of #20 AWG wire cable fitted at one end with a spade-lug, and an alligator clip at the other. An
additional 4 ft. length of this wire cable is soldered to the alligator clip.
Fig. 5 Grounding Hydrosol Holder
To assure that the grounding lead(s) will perform as manufactured, an electrical continuity check
should be made prior to connecting to the holder.
If the continuity check proves acceptable, connect the spade-lug to the grounding screw located on
the bottom of the Hydrosol base.