oxycodone/oxymorphone separation

<p><span>Does anyone have a UPLC procedure for the separation of oxycodone and oxymorphone they would be willing to share? I am interested in column and mobile phase chemistries primarily.</span></p><p><span>Thanks</span></p>


  • these compounds seem to be prone to fronting

  • You may have success with a BEH Phenyl column. Mobile Phase A: 5mM ammonium bicarbonate pH 10.5 (use NH4OH to pH)/MeOH 90/10 Mobile Phase B: Acetonitrile Column Temp 50 deg C flow rate 0.7ml/min

    Isocratic or Initial conditions for a gradient A:B 70:30

    Tailing for Oxycodone should be 1.1 - 1.2

  • Great advice Kenneth. I will certainly try your methodology. I wouldn't be opposed to hearing a promising HILIC methodology either.

  • Hi,

    You may try,

    Column : BEH HILIC Column, 2.1 x 100 mm, 1.7 µm

    Mobile : 85:15 {0.1% ammonium acetate in acetonitrile:0.1% ammonium acetate in water, pH 4.2}

    WL: 254

    Column temp. : 40C

    Flow: 0.5

  • Thanks for the great advice. Are either of these recommendations currently being utilized for oxycodone/oxymorphone analysis?

  • try:

    10mM orthophosphate buffer at pH 8.30

    BEH C18 30 x 2.1 mm,

    Acetonitrile ramping from 5 to 50% over 1.1 minutes at a flow rate of 1.5 mL/min, remainder buffer.

    Temperature = 50oC

    Oxymorphone RT = 0.5 min, Oxycodone RT = 0.8 minutes


  • What kind of resolution are you getting with that setup?

  • If you're fronting, you're likely overloading your column. Dial down the injection volume or the concentration of the finished sample, or a combination of both.