DHA
Answers
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I've used UPLC-ELSD for this type of application. In a clean matrix, glycerol can be measured using ELSD with a HILIC type column, BEH Amide or Prevail Carbohydrate ES (WR Grace) column, drift tube temp=35C, nebulizer=cooling, 50psi, flow rate=0.5-1.5mL/min (depending on column/particle dimensions), column temp=60C+ (BEH Amide) or 60C (Prevail). I use isocratic 75:25 acetonitrile:water with 0.2% triethylamine. The glycerol elution time is just after the solvent front. If the matrix is dirty, you would need to adjust the mobile phase/flow rate to increase retention.
I use a straight silica (monolithic) column under normal phase conditions (isooctane/ipa/water ternary gradient) to monitor FFA content. However, there is no selectivity with this method, as you will obtain only one peak containing all FFAs. A diol column should also work.
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