My column is fairly new and clean and operates well in other HPLC instruments, my method is a gradient elution method, and my solvents are ACN and water. I have removed the column and set a union in that column space and I am still getting the same ghost picks. I have cleaned the instrument with the following solvents, isopropanol, methanal, warm water, and acetone and still I have the same problem, I cannot even get to the stage of analyzing as these picks appear while I am still trying to stabilize the baseline, the look like there's a separation. Can anyone with information assist? I have used different flow rates, and compositions, I am currently cleaning with 100% isopropanol with a flow rate of 1ml/min.
You have several problems.
1. Your sensitivity is too high and thus not relevant when compared with the API peak (normally over 50,000 peak area units).
2. These are electrical spikes and can be eliminated by inserting a common surge protector between the HPLC instrument and its electrical supply (120 V).
3. ....
Dear Sisonke Olothando Sigonya,
the problem can have several causes.
That you have shot out the column by the Union is valuable information.
First, consider what changed before the phenomenon.
For example, new seals in the pump, Autosampler needle/needle seat replaced, Pump inlet/outlet valves replaced....
Other events such as electrical short in the lab, etc.
It can also be a component of a previous sample that has settled in the system and is now being flushed through the system depending on the eluent composition. For this purpose, here is a cleaning tip:
Rinse the system without column for 2-4 hours with a mixture of 65% propanol-2, 30% methanol, 5% chloroform or dichloromethane. With this mixture I rinse in our laboratory the HPLC system for our LC-MS equipment.
Another cause can be in the system itself, e.g. a contaminated detector cell:
Impurities cannot always be completely removed from the system, especially if such an impurity has precipitated and is slow to dissolve again.
Intensity fluctuations of the UV lamp:
UV lamps in HPLC instruments usually have a lifetime of 1000- 2000 hours. In the last hours of operation of such a lamp, poor ignition behavior can occur, i.e. the lamp needs a longer time to start after initial warm-up. it can also occur "flickering", i.e. rapid changes in intensity that last only a few seconds. Your chromatograms indicate that this is your problem, as the signals appear sporadically and are not chromatography related. You should run a detector test with your system once. You will find such a test in all common software versions of the respective manufacturers.
Last but not least, fluctuations in the power supply could also be a cause, e.g. the amplifier power fluctuates.
I hope I could give you some useful tips. Good luck with the elimination of the problem
Many greetings
Joachim Horst
Have you cleaned suction filters? If no, please clean those well. If yes, I think your system needs detector cleaning. You may take local service providers help to clean detector.
Dear Sisonke,
I have read your question. If ghost peak is persisting then either it is electric spike peak or secondly, you can use Ghost buster column for such peaks. There is no impact on chromatography because the attachment of ghost buster column is before pump i.e before entering mobile phase in column.
you can check ghost buster column with B3PHARMASOLUTION Maharashtra (INDIA) [email protected].
Your issue of getting ghost peak will be resolved.
feel free to write if query any.
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