How do you troubleshoot an HPLC?

HPLC troubleshooting

1. No pressure reading, no flow. Possible cause.
2. Now pressure reading, flow is normal. Possible cause.
3. High back pressure. Possible cause.
4. Low back pressure. Possible cause.
5. Fluctuating pressure. See section High back pressure.
6. Pressure dropping to zero.
7. Pressure dropping, but not to zero.
8. Pressure cycling.

How do I know if my HPLC column is bad?

Symptoms of deterioration are poor peak shape, split peaks, shoulders, loss of resolution, decreased retention times, and high back pressure. These symptoms indicate contaminants have accumulated on the frit or column inlet, or there are voids, channels, or a depression in the packing bed.

What is the reason for pressure drop in HPLC?

A pressure being constantly too low can be a sign of a small leak or air bubbles in the pump system. Do not forget the obvious reasons, such as a too low flow rate or different column temperature. Even a blocked suction filter in the solvent bottle can lead to reduced pressure.

Why are there no peaks in HPLC?

If you are getting absolutely no peaks on your output, you may have no flow in your HPLC column. This may mean your pump is off or the flow is interrupted or obstructed somehow. You may also have a leak or air trapped in the pump head.

How do I fix tailing in HPLC?

There are a few methods that can be used to avoid peak tailing:

1. Operate at a lower pH.
2. Use a highly deactivated column.
3. Consider the possibility of mass overload.
4. Consider the possibility of column bed deformation.
5. Work at high pH when analyzing basic compounds.
6. Use a sample clean-up procedure.

How do I clear a blocked HPLC column?

First, wash the column with varying solvents at a low flow rate. However, if your column is so clogged that it can’t flow at all, flip the column and run it in the opposite direction. If all else fails, then you might need a new column.

What is the difference between high pressure and low pressure HPLC?

Mixing takes place on the low pressure side of the pump and a single pump is operated at a constant flow rate. High pressure gradient systems are composed of two pumps. These systems are limited to two solvents which are pumped by the separate pumps.

How do I lower my HPLC pressure?

Filtering samples, using high-quality solvents (or filter solvent), and routine system maintenance are all recommended to prevent excess pressure in your HPLC column and system.

What is needle wash in HPLC?

The 2018 Alliance HPLC System employs a flow-through needle design and includes multiple wash modes to clean the exterior of the injector needle1 with an appropriate wash solvent. Optimization of the needle wash composition and wash mode can significantly reduce sample carryover.

How do you stop tailing?