LC Leak Checking
Leaks are one of the most common problems users encounter when performing liquid chromatography. Even the smallest leak in your LC system can cause a loss of sample, a drop in efficiency, and break your entire analysis workflow.
In this Restek Tip, we investigate the signs of a possible leak and outline the troubleshooting steps you should take if a leak is discovered.
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Leaks are one of the most common problems that users encounter when doing liquid chromatography. Even the smallest leak in your system can cause a loss of sample, a drop in efficiency, and break your entire analysis workflow.
In today’s Restek Tip, we’re going to explore the signs of a possible leak and what you should do if a leak is discovered.
Modern LC instruments have sensitive leak detectors in every component, so if the system detects a leak, the pumps will automatically shut off to avoid a solvent spill. Unfortunately, this also means that any current run or batch will stop too.
But even if the instrument doesn’t detect a leak, one could still be present if you notice a loss of retention, signal response—and most importantly—pressure! So, what should you do?
If the instrument displays a leak error code, start by visually inspecting every component of your LC.
If you see where the leak is coming from, tighten the tubing with the appropriate wrench.
If the leak is occurring at the inlet of the LC column, make sure the end-fittings between the mobile phase tubing and the column are tightened and secured; taking care not to overtighten and damage the fitting.
If a leak is still present, remove the fitting and inspect it for any signs of damage. You can also consider using high-pressure fittings, which are more durable.
What if the source of the leak is not easy to find?
Start by following the entire mobile phase flow path with a lab wipe. Watch the wipe for any signs that it’s absorbing liquid, and then troubleshoot the affected component according to the manufacturer’s recommendations.
Modern instruments will not start again until the leak detector is completely dry, so use a clean lab wipe to dry the area first, then wait a couple of minutes before restarting the system.
Solvent leaks can happen at any time, so we recommend making leak checking part of your routine maintenance by looking for any residues or moisture.
Also check for worn or damaged parts, so you can replace them before a leak occurs.
If you have any questions about leak checking your instrument, contact us at restek.com. Thank you for joining us for this Restek Tip!