HPLC

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  1. ManicMetalhead's Avatar
    • Respected Member
    • Location: England
    • Posts: 175
    HPLC
    Now this may sound like an incredibly stupid question, but I've run a load of HPLC samples, and got the chromatograms and values for each sample. My problem now is, where on earth do I start with analysing them?

    Any helping hints or starting points are massively appreciated
  2. cpchem's Avatar
    • Vengeful, Imperial Overlord of The Student Room
    • Location: Bristol
    Re: HPLC
    (Original post by ManicMetalhead)
    Now this may sound like an incredibly stupid question, but I've run a load of HPLC samples, and got the chromatograms and values for each sample. My problem now is, where on earth do I start with analysing them?

    Any helping hints or starting points are massively appreciated
    Well, it depends on what you've been HPLCing and how, doesn't it?

    Normal-phase, reverse phase? What compounds have you been running? Visualising by fluorescence at 254nm?
  3. ManicMetalhead's Avatar
    • Respected Member
    • Location: England
    • Posts: 175
    Re: HPLC
    (Original post by cpchem)
    Well, it depends on what you've been HPLCing and how, doesn't it?

    Normal-phase, reverse phase? What compounds have you been running? Visualising by fluorescence at 254nm?
    Capsaicin (hot compound in chilli's)

    Reverse phase,
    UV detector set to 280nm
    1ml/min
    7 minute run time

    Ran a few standards of pure capsaicin, and then made up and ran solutions of each chilli I had.

    What else is there?
  4. cpchem's Avatar
    • Vengeful, Imperial Overlord of The Student Room
    • Location: Bristol
    Re: HPLC
    Ah, so you're doing quantitative work rather than trying to work out what compounds you've got. Nice one.

    So, if you've done several runs of pure compound at varying concentrations, you should be able to plot a calibration curve (concentration of capsaicin against the integral of the peak).
  5. ManicMetalhead's Avatar
    • Respected Member
    • Location: England
    • Posts: 175
    Re: HPLC
    Yeah, the calibration curve I can do, I just wasn't sure what to do with my results afterwards. I kinda get to the calibration curve, then hit a block and don't know what to do from there.
  6. cpchem's Avatar
    • Vengeful, Imperial Overlord of The Student Room
    • Location: Bristol
    Re: HPLC
    (Original post by ManicMetalhead)
    Yeah, the calibration curve I can do, I just wasn't sure what to do with my results afterwards. I kinda get to the calibration curve, then hit a block and don't know what to do from there.
    Then you start working in reverse. You've got samples of unknown capsaicin concentration, but you know (from the HPLC traces) the peak integrals. Use your calibration curve to go backwards - from the integral of the capsaicin peak, you should be able to read a concentration from the graph.
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