Quantities
Process
Equipment
Troubleshooting
Problem Indicators
100
How many pH probes should there be installed on the UF/DF skid?

1

100

What does TFF stand for? Do we use it in our UF/DF process?

Tangential flow filtration, yes.

100

Where do you pull permeate and retentate samples?

Permeate-on the skid and retentate- bag

100

What could happen if air is introduced into the LevTech?

Foaming and protein loss. 

100

How can excessive foaming impact the product?

Could damage the product.

200

How many ports are there on the transfer panel?

3
200

Throughout UF/DF, when do we perform an airpurge?

During manifold flush

200

What should the air regulator be set to?

30psig

200

The retentate bag's weight keeps slowly dropping although nothing is running.

Observe bag for leaks. Check sampling manifold for any open ports. Observe scale for abnormalities. Escalate.

200

High TMP could indicate what? Low TMP could indicate what?

High: Cassettes are clogging Low: cassettes are compromised.

300

How many pressure sensors should there be on the UF/DF skid?

4

300

Prior to starting the product transfer, what needs to be done?

Filter needs to be flushed, retentate bag samples must be pulled, and gross weight is obtained.

300

How many ports are there on the skid and what is each one used for?

4- WFI, Sani, Recovery, and Re-circulation

300

During product transfer, the flow is very slow and the transfer is taking longer than usual, what should I do?

Observe and manipulate manifold for any hardening of the tubing. Purge air from the filter. Escalate.
300

Hardening of tubing during process

Ensure flow path is open. Escalate.

400

From start to finish of the UF/DF process, how many times is SoloVPE utilized for protein concentration? 

3
400

What happens during UF and what happens during DF?

UF- Concentrating down 

DF- Buffer exchange

400

What final pressure should the cassettes be torqued to?

1700-1900psi.

400
When performing SOLO, I received a protein concentration that's outside the specified range, what should I do?

Most likely, you will have to re-perform a new sample but this time let the line flush to drain longer. Follow tree in SOLO SOP. 

400

During transfer, pump is not ramping to set point.

Escalate.

500

How long is the pressure hold during the pressure test?

5 minutes

500

What criteria is used to separate components in a liquid solution?

Molecular size or weight.

500

What is TMP and why is it important?

Transmembrane pressure which is the pressure difference between the two sides of a membrane. It ensures protein retention is maximized without damage or loss of protein.

500

When starting recovery, you get this prompt "Calculated post recovery concentration = ___. Target post recovery concentration = ___. Selection (1) to proceed with calculated concentration. Select (2) to return to previous prompt. 

Escalate to supervisor and potentially process leads.

500

What could happen if the bottom diaphragm of the skid is not tightened properly?

Since the first thing you run through the skid is WFI and that part acts as a valve, it could gush out instead of flowing straight through the skid.