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Issue |
Possible Cause |
Action |
Poor mobility and reproducibility |
Temperature fluctuation |
|
Blocked, dirty capillary |
Change capillary |
|
Sample-wall interaction |
Rinse capillary with polymer |
|
Ion depletion of buffers |
Replace buffers |
|
Buffer siphoning |
Buffer reservoir levels not equal |
Equalize buffer levels |
Poor sensitivity |
Not enough amplified product in sample |
Reamplify or add more amplified product |
Bubble in sample tube, capillary exposed to bubble |
Reinject |
|
Poor laser power |
Service call, possible laser replacement |
|
Ion competition during electrokinetic injection |
|
|
Poor matrix |
Rerun matrix |
|
Gradual change in current |
Different cathode/anode buffers and/or concentration |
Confirm buffers |
Current fluctuations |
Bubbles in the system |
Conduct a visual check for bubbles and clear by flushing with fresh polymer. |
No current |
Plugged capillary |
|
Wrong buffer |
Confirm buffers |
|
Noisy baseline |
Poor matrix |
Rerun matrix |
Flat baseline |
Capillary not aligned in detector window |
Realign capillary |
No voltage |
|
|
Sample not injected |
Confirm the following:
|
|
Laser not functioning |
Service call, possible laser replacement |
|
Clogged capillary |
|
|
Electrical arcing |
Buffer spill in high voltage areas |
Clean autosampler tray with distilled water and wipe dry |
Poor peak shape |
Incorrect current causes: peak distortion tailing [low current] |
Replace buffer |
Capillary failure |
|
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