17
Filta-Max
xpress
Operator’s Guide
10. Open the Filter Housing, remove the Filter Module, and discard the Filter Module according to
appropriate disposal regulations.
IMPORTANT:
All Filter Modules should be autoclaved according to your standard autoclave
waste disposal cycle.
11. Cap the centrifuge tube, and remove it from the collection vessel holder.
Note:
The Pressure Elution Station contains several sensors. The Pressure Elution Station will
not start an elution cycle if the centrifuge tube, the Filter Housing, or the outlet diverter are not
in place. At the end of an elution cycle, the Pressure Elution Station will not start the next cycle
unless the centrifuge tube is removed from the collection vessel holder and replaced with a
fresh tube.
12. Clean the QC stem on the Pressure Elution Station with alcohol-soaked wipes.
13. Proceed with subsequent sample elutions.
Concentrating the eluates and resuspending the pellet before IMS
After eluting the samples, you must concentrate the eluates further by centrifugation before
purifying them by immunomagnetic separation (IMS).
Centrifuge requirements (e.g., Hettich* Rotanta 460)
• Swing-out rotor
• Inserts and support cushions for 500 mL centrifuge tubes
• In good working order, with bucket supports lightly greased
Centrifuge setup
• Locate centrifuge to minimise vibration.
• Set RCF to 2000 × g.
• Set acceleration to maximum and deceleration to minimum, with the minimum amount of
braking possible.
• Set time to 15 minutes, excluding ramp-up time.
To concentrate the eluates:
1. Balance the centrifuge tubes (collected in step 11 of
"Eluting the sample" on page 16
the cushions, and the centrifuge buckets to within 0.5 g of each other.
Note:
Failure to balance the tubes correctly can result in centrifuge imbalance and can affect
the target sedimentation efficiency due to excessive vibration.
2. Centrifuge the samples at 2,000 × g for 15 minutes (not including the time taken to reach
2000 × g), allowing the centrifuge to coast to a stop at the end of centrifugation.
DO NOT
USE THE BRAKE.
Note:
The deceleration profiles of different centrifuge models can vary. For optimal
performance, the centrifuge should not be braked during deceleration. Check the operator’s
guide provided with the centrifuge or the centrifuge vendor’s technical service department for
the centrifuge deceleration profile. Deceleration via braking can reduce method performance
during this procedure.
The sample separates into supernatant and concentrated eluates, which often form a pellet at
the bottom of the tube.