Bio-Rad Profinia™ Protein Purification Instrument - Manual (Page 180)

Problem Solution
If there aren’t problems noted with sample application, use
the “Check Flow Rate” utility (section 9.2.2) to check if the
flow rate is correct. If the flow rate is low, possible causes
are:
•
Inline filter — replace the inline filter, and repeat the flow
rate check
• Pump check valves — run the system NaOH wash to
clean any contamination from the check valves. Check
the flow rate again. If the flow rate is still low, disassemble
and clean the check valves
• Pump seals — if cleaning the check valves does not
resolve the problem, replace the pump seals
Method runs longer Check the method temperature setting (section 9.3.13). If the
than expected system is set for low temperature (4°C), flow rates are slower
and the method will take longer to run.
Leaks at cartridges If you see leakage at the cartridge inlets or outlets, first tighten
the locking collars. If this does not stop the leakage, replace
the cartridges.
Leaks to the benchtop The most common cause of leakage to the benchtop is an
overflowing waste bottle or fraction tube. If this is not the
cause, remove the cover of the fluidics compartment (section
13.2) and check for leaks caused by loose fittings or damaged
tubing. When replacing tubing, use the same size and length
tubing (section 13.2.5).
Uneven UV baseline If the UV trace wavers excessively, first check and replace
the system inline filter (a clogged filter may cause bubbles in
the fluid). If this does not resolve the problem, go to the
Manual Operation screen (section 9.3.2) and check the
intensity of the UV lamp and the signal/reference voltage
ratio. It may be necessary to replace the UV lamp, or clean
the UV flow cell.
Different readings Check UV lamp intensity and signal/reference voltage ratio
between UV monitors (section 13.2.3), clean the flow cell, or change the UV lamp if
necessary. You may calibrate the UV monitors with a protein
solution to match the readings.
Protein estimates are Protein absorbances vary; use the UV monitor calibration
not as expected utility (section 9.2.3) to calibrate the system with a protein
similar to your samples.
Incorrect conductivity If the conductivity monitor does not display the proper
reading reading, use conductivity standard solution (10 mS) to
calibrate the conductivity meter.
Incorrect pH reading Recalibrate the pH probe using the pH calibration utility
(section 9.2.6).
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