Analytical filtration bacterial analysis water membrane filtration drinking pollution testing Apparatus for Analytical Filtration of Water Samples - the FiltrABut Function The "FiltrABut" can be used for water sample membrane filtering in bacterial analysis of water. Useful distinctions from the analogues. Direct filtration of water sample from the sampler-bottle; without pouring the sample from the sampler-bottle into the filter funnel. Possibility to interrupt the sample filtration and change the filter at any moment. Second sample contamination probability is minimal, because of the water - apparatus contact area is very small. Working pose is sitting (More comfortable for the operator). Principle of operation The membrane filter 1 is set on the base 2 (with a support screen), pressed to it by bottle holder 3 by means of the captive nut 4 (which is not shown on the other plans for visibility advance) and the taper joint 5 is locked with the ball cock 6. The complete filtering head FH is turned upside-down and set on the neck of sampler-bottle 7. The resulting assembly is turned upside-down and taper joint 8 is locked with the filtrate collector 9, which is connected to a suction device and equipped with a vacuum-gauge 10 and a rarefaction regulator 11. Some quantity of liquid flows out from the bottle-sampler 7 into the space over filter 1 in holder 3 . As a result the pressure above liquid in the bottle-sampler 7 decreases and the difference between the one and atmosphere pressure holds the liquid column in the sampler-bottle 7. The cock 6 is opened and liquid filters from the space over filter 1 through it under the action of rarefaction in the collector 9. Liquid level in the space over filter 1 comes down uncovering the rim of sampler-bottle neck and an air bubble enters the sampler-bottle 7, replacing a liquid portion in it, which again shuts down air inlet in the sample-bottle. This phenomenon repeats then. When the required volume has been filtered, the cock 6 is closed and the assembly of sampler-bottle 7 together with filtering head FH is overturned back. At that the liquid, placed above the filter 1, flows down inversely into the sampler-bottle 7, but the particles are retained on the filter 1 owing to differential pressure remaining on the filter 1 due to closed cock 6 and to impermeability of the wet membrane filter for air. The filtering head FH is pulled off the sampler-bottle neck, disassembled, the filter 1 is changed by a new one and the next portion of liquid is filtered. Performance attributes Filter diameter, mm 35 or 47 Sterilization of the base 2, holder 3 and bottle neck by flaming Suction by any appropriate device. Contact area of sample with the bottle holder – 4 sm^2. Sampler-bottle is in preference the hospital volumetric glass bottle for dropper. PRICE ...............