3 ways to get rid of %Carryover in HPLC system

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 %Carryover in HPLC system is the residue which interferes during routine analysis on HPLC which impacts the actual results. This is one of the most common problem which every analyst encounters during HPLC analysis. Though as a part of system limitations there are certain acceptance criteria for % Carryover i.e. it should not be more than 0.1% of the principle peak, as a common practice.

It is very easy to get rid of such %carryover by following three (3) methods:

1) Injection pattern: During analysis injection pattern matters a lot. If high concentration solution is injected first followed by low concentration silution then %carryover is more. So if any high concentration solution is injected it should be followed by blank injection to avoid any %carryover. This is acceptable even by the auditors if more blanks are added. This can also avoid creation of any type of lab events or incidences.

2) Frit cleaning: There is a part called frit after which solution pass into the detector in HPLC system. If too much of carryover is observed then frit shall be changed. This a very effective way to get rid of %carryover. Moreover it can also be sonicated in a mixture of IPA-Water mixture and re-used.

3) Column retention: Sometimes there are certain molecules which are hard to clean from HPLC column. Due to this type of retention %carryover is observed. To avoid such carryover, column should be washed thoroughly in solvent, in which that particular molecule is soluble.

Hope above tips will help you during your next HPLC analysis.


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