Running the LC-MS with concentrated sample

Hi everyone,

If I ran the LC-MS with a highly concentrated sample, will it contaminate and de-sensitize the detector in the QTOF? If so, is there any ways to get rid of these contaminants? Thank you.

Parents
  • You should avoid, if possible, injecting highly concentrated samples since they can precipitate (clogging lines) when mixing with mobile phase and can introduce background which can give ion suppression (lower signal of analytes due to background ions).  Diluting the sample before analysis or injecting very low volumes (0.1 ul) may work.  A common way to reduce analyte retained in the HPLC system would be to do blank runs and to flush the HPLC with a solvent that is solubilizing and eluting.

    If you need to inject a high concentration sample, using a needle wash with a solubilizing solvent is recommended to avoid introducing analyte in the autosampler needle seat.

Reply
  • You should avoid, if possible, injecting highly concentrated samples since they can precipitate (clogging lines) when mixing with mobile phase and can introduce background which can give ion suppression (lower signal of analytes due to background ions).  Diluting the sample before analysis or injecting very low volumes (0.1 ul) may work.  A common way to reduce analyte retained in the HPLC system would be to do blank runs and to flush the HPLC with a solvent that is solubilizing and eluting.

    If you need to inject a high concentration sample, using a needle wash with a solubilizing solvent is recommended to avoid introducing analyte in the autosampler needle seat.

Children
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