Miltenyi Biotec MACSQuant Tyto Cell Sorter Mode D'emploi page 50

Low yield
A low yield after sort can have multiple reasons:
Event detection gain settings (voltage) are too low.
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Noise threshold and/or trigger threshold cut off target events.
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Backscatter signals are clipped for the used sample.
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Alignment of cartridge is incorrect.
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Concentration of target cells is higher than expected.
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An air bubble is in the channel or the sort chamber (refer to The sort channel is clogged on the previous page).
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Debris clogs the sort channel (refer to Valve is not moving on page 46 and The sort channel is clogged on the
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previous page).
Do one or all of the following:
Check setup of event detection settings (refer to the MACSQuantify Tyto Software user manual).
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Check noise threshold and trigger threshold. The thresholds should not cut off any target events.
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Verify that backscatter signals are not clipped for the used sample. Adjust the backscatter gains if needed.
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Backgating of the target events in the BSR/BSB and BSV/BSB plots can help to identify the target events in the
backscatter plots (refer to the MACSQuantify Tyto Software user manual). If the backscatter signals are still
clipped, contact Miltenyi Biotec Technical Support for assistance.
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If cartridge alignment is off, eject cartridge and start again.
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Verify sample concentration and adjust sample concentration accordingly.
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Select Automated pressure adjustment or adjust pressure manually to reach a transit time of 40 µs for regular
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speed cartridges or 20 µs for high-speed cartridges. If it is unclear which cartridge type is used and whether it
is suitable for e.g. high-speed sorting, refer to the data sheet of the respective cartridge.
Eject cartridge and transfer cells to a new one.
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Low purity of target cells
A low purity of target cells in sort can be caused by:
Concentration of target cells is higher than expected.
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Low frequency of target cells.
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Do one or all of the following:
Verify sample concentration and adjust sample concentration accordingly.
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Immunomagnetic pre-enrichment or two-step sort.
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