Has anyone has success with the USP assay for fosfomycin?

I am trying to develop a method for the quantification of fosfomycin.  My starting point has been the USP monograph for fosfomycin, but I am detecting nothing.  We are running a 1260 Infinity II Prime with the RID detector.  I am confident that I am injecting comparable amounts to the documented method.  I am using a Polaris 5 NH2 250 x 4.6 mm, 5 um column. Any advice would be welcomed.

Parents
  • first you need to make sure that your nh2 column is good

    you know NH2 columnS are very easy to be damaged

    second thing is to inject a higher concentration to see your peak

    RID detectors are not sensetive at all

    so you need to have both good column and sufficient concentration.

    some papers use Hillic columns and others use ion exchange to derect the phosphomycin

    ..

    finallyif every thing works bad with you, try to derivative your analyte or try to use ESI LC MSD if you have one in your LAB

Reply
  • first you need to make sure that your nh2 column is good

    you know NH2 columnS are very easy to be damaged

    second thing is to inject a higher concentration to see your peak

    RID detectors are not sensetive at all

    so you need to have both good column and sufficient concentration.

    some papers use Hillic columns and others use ion exchange to derect the phosphomycin

    ..

    finallyif every thing works bad with you, try to derivative your analyte or try to use ESI LC MSD if you have one in your LAB

Children
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