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TROUBLESHOOTING
SYSTEM INSTALLATION AND SETUP
Problem
Possible Cause
Negative peaks.
The sample is applied to
the column in a different
buffer from that used to
equilibrate and elute the
column. Refractive index
changes may be
responsible for the
negative peaks.
1. Apply the sample in the same buffer used to
equilibrate the column.
The elution buffer may
have a higher UV
absorbance than the
sample components.
2. Check the elution buffer’s UV absorbance.
The injection valve,
injection port, and loop
were not rinsed out
between sample
injections.
1. Rinse valve, port, and loop with buffer. For
example, if the sample loop contains 100 µl, then
program a load/inject volume of 200 µl to
completely flush the valve and loop.
False or ghost
peaks.
Suggested Solutions
2. Always clean large volume dynamic loops, such as
the Bio-Rad DynaLoop™, between use to avoid
cross contamination.
Strongly-retained sample 3. Use stringent elution conditions or consult the
components may still be
column’s user manual for an appropriate wash
eluting from a previous
step to remove such components between runs.
run.
6-4