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Usage Tips
1. Flow Rate
Filtration rate is affected by several parame-
ters, including MWCO, porosity, sample con-
centration, viscosity, centrifugal force and
temperature. Expect significantly longer spin
times for starting solutions with over 5%
solids. When operating at 4°C. flow rates are
approximately 1.5 times slower than at 25°C.
Viscous solutions such as 50% glycerine will
take up to 5 times longer to concentrate
than samples in a predominantly buffer
solution.
2. Pre-rinsing
Membranes fitted to Vivaspin
®
concentrators
contain trace amounts of Glycerine and
Sodium azide. Should these interfere with
analysis they can be removed by rinsing fill
volume of buffer solution or deionised water
through the concentrator. Decant filtrate
and concentrate before processing sample
solution. If you do not want to use the
pre-rinsed device immediately, store it in the
refrigerator with buffer or water covering
the membrane surface. Please do not allow
the membrane to dry out.
3. Sterilisation of Polyethersulfone
Membranes
Polyethersulfone membranes should not
be autoclaved as high temperatures will
substantially increase membrane MWCO.
To sterilise, use a 70% ethanol solution or
sterilising gas mixture.
4. Chemical Compatibility
Vivaspin
®
concentrators are designed for use
with biological fluids and aqueous solutions.
For chemical compatibility details, refer to
table 4.