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6.7 Selecting the appropriate tube rack
Three different tube racks are available for processing sample volumes between
0.2 mL and 50 mL. Unless otherwise specifically indicated in the Cell Separation
Reagent data sheet, the magnetically labeled cell samples are resuspended at 10⁸
total cells per 500 µL when using manual labeling. The cell numbers and volumes
for autolabeling are slightly different. Refer to table 6.3 for further details.
• Row A of the Chill Rack holds the sample tubes (Ori).
• Row B of the Chill Rack holds the tubes for the non-labeled fractions
(negative fractions, Neg).
• Row C of the Chill Rack holds the tubes for labeled fractions
(positive fractions, Pos).
• Optional: For your convenience, Row D can hold round-bottom tubes for further
analyses.
Select the appropriate tube rack according to table 6.4. It is recommended to cool
down the tube rack for 3–4 hours in a refrigerator (2–8 °C) or until the coolant
becomes solid. Do not cool below 0 °C, as samples may freeze. Tube racks will stay
cool for 2-2.5 hours. Equip the tube rack with sample tubes and fraction collection
tubes.
Rack type
and
symbol
Slots
Maximal
number of
samples
Manual
labeling
Autolabeling
Maximal
sample
volume
Minimal first
incubation
volume
Maximal final
labeling
volume
Chill 5
24×5 mL
6
(5 mL tubes)
2.5 mL
0.2 mL
0.25 mL*
2.0 mL
1 mL*
Chill 15
15×15 mL
5×5 mL
5
(15 mL tubes)
12.5 mL
0.2 mL
1 mL*
6.5 mL
4 mL*
Chill 50
6×50 mL
3×15 mL
3
(50 mL tubes)
50 mL
4 mL*
8 mL*
*Volumes refer to whole blood samples only.
Table 6.4: MACS Chill Rack specifications for manual labeling and autolabeling.
