Abstract:

A method was developed for the simultaneous determination of canthaxanthin and astaxanthin in feedstuffs
using reversed-phase high performance liquid chromatography （RP-HPLC）. The sample was extracted by acetonitrile,
and cleaned up by an LC-NH2 column. An Agilent ZORBAX Eclipse XDB-C18 analytical column (150 mm×4.6 mm, 5 μm) was
used and kept at 25 ℃. Acetonitrile-methanol (95∶5, v/v) was used as the mobile phase at a flow rate of 1.0
mL/min. The detection was performed by a diode array detector at 474 nm. The quantitive analysis of external
standard calibration curves was used. The linear ranges of the method for canthaxanthin and astaxanthin were 1.0-
30.0 mg/L (r=0.9990) and 1.0-20.0 mg/L (r=0.9991), respectively. The average recoveries were 90%-101% with the
relative standard deviations of 0.62%-3.68%. The detection limits were 0.84 and 0.60 mg/L for canthaxanthin and
astaxanthin, respectively. The method is simple, precise, sensitive and reproductive. It can be used to determine
the contents of canthaxanthin and astaxanthin in feedstuffs.

Key words:
canthaxanthin, astaxanthin, feedstuffs , reversed-phase high performance liquid chromatography (RP-HPLC), solid phase extraction (SPE)