HPLC Determination of β-Carotene in Compound Vitamin Tablets

A method of HPLC for the determination of β-carotene in compound vitamin tablets was proposed. The sample was saponified and extracted with petroleum ether, and the extract was concentrated in a rotary evaporator and the residue was dissolved with CH2Cl2. The β-carotene was separated on ODS-C18 column(150 mm×4.6 mm, 5 μm) with mixed solution of methanol and isopropanol (1+1) as mobile phase, and determined at the wavelength of 448 nm with UV detector. Linear relationship between values of peak area and mass concentration of β-carotene was obtained in the range of 0.10-50.0 mg·L-1, with detection limit (3S/N) of 0.03 mg·L-1. The proposed method was applied to the determination of β-carotene in compound vitamin tablets, giving values of recovery obtained by standard addition method in the range of 90.0%-95.0% with RSD′s (n=6) in the range of 0.86%-3.2%.