SCYM Cell Sorting 4

Question 1

What is the primary advantage of microfluidic (chip-based) cell sorting compared to conventional droplet-based FACS?

Accepted Answer

A closed, contained fluidic path that reduces aerosol biohazard risk

Answer

Chip-based microfluidic sorters keep the sample in a sealed cartridge, dramatically reducing aerosol generation and making them safer for sorting BSL-2 or BSL-3 samples.

Question 2

Which type of sort purity verification is recommended immediately after collecting a sorted fraction?

Accepted Answer

Re-analyzing a portion of the sorted sample on the same or a validated cytometer

Answer

Re-analyzing a portion of the sorted fraction on the cytometer is the standard method to verify that the collected cells match the target gate.

Question 3

In a clinical or GMP-compliant cell sorting environment, which factor is most critical to document for regulatory purposes?

Accepted Answer

Chain of custody, sort parameters, sterility testing, and instrument QC logs

Answer

GMP sorting requires comprehensive documentation including chain of custody records, validated instrument QC, sort parameters, and sterility testing to satisfy regulatory requirements.

Question 4

What is the main reason to use a low-pressure (low-PSI) nozzle when sorting fragile primary cells?

Accepted Answer

Lower pressure reduces shear forces, improving post-sort cell viability

Answer

Fragile cells, such as neurons or activated T cells, are susceptible to mechanical damage from high shear forces; lower pressure nozzles reduce these forces and improve viability.

Question 5

When sorting rare populations (less than 0.1% of events), which strategy best improves efficiency?

Accepted Answer

Pre-enriching the sample using magnetic bead selection before FACS sorting

Answer

Pre-enriching the sample with magnetic beads increases the frequency of the target population before sorting, dramatically reducing sort time and improving recovery.

(SCYM) Specialist in Cytometry Practice Test

(SCYM) Specialist in Cytometry Practice Test

SCYM Cell Sorting 4