| The contents of DHA and EPA in fish oil health products were determined by gas chromatography internal standard method. The samples were treated by transesterification and the chromatography condition was optimized. The method was verified by linear relationship, precision, repeatability, stability and recovery of standard. The contents of DHA and EPA in fish oil health products from ten different manufacturers were evaluated. The results showed that mass concentrations and peak areas of EPA and DHA had good linear relationships in ranges of 5.57-278.50 μg/mL and 6.97-348.50 μg/mL respectively (R2=0.999 6, 0.999 1). The precision (RSD=0.43%, 1.05%), repeatability (RSD=104%, 1.62%), stability (RSD=1.48%, 1.27%), and accuracy (recovery rate 100.47%, 10143%) were good. The qualities of ten samples were uneven, and the quality specification should be improved. The method showed good accuracy and high precision, which could be used for the determination of EPA and DHA contents in fish oil health products. |
