Lycopene by HPLC-DAD

[carlos.teixeira]

Dear Friends,

I need one suggestion for analyse Lycopene by HPLC. I have C8 and C18 columns. But my great problem is the stability of this analyte, I worked on dark condition (yellow light), but the Lycopene peak decresed (argh).
Anyone has expertise with this analyse.

Thanks

Carlos Teixeira

[Bruce Hamilton]

I'm fairly certain that the most recent US Pharmacopeia has Dietary Supplement monographs on Lycopene and/or Tomato Extract which contain HPLC method for analysis for lycopene. I'd start by looking at those, or some other published literature.

Bruce Hamilton

[Biocheckup]

We do it routinely on human serum after hexane extraction. Lycopene is rather robust compared to other carotenoids.

We use a red light (photo lab style).
Use high quality organic solvents, check for metal traces, remove oxygen, evaporate solvant under nitrogen if needed, do not exceed 35 °C in any step.
Put between 0.01 and 0.1 percent of butylated hydroxytoluene (BHT) in every organic solvent (mobile phase included) used in your procedure. Don't put too much BHT, it mave have adverse (pro oxidant) effects.

[Mark Tracy]

Standards are another sore point. Your stock solutions will change with time, despite the best care, and need to be re-assayed every time you make working dilutions; I did it by spectrophotometry using published absorbtion coefficients.

I found the AOAC methods for carotenoids full of helpful advice and information.