RESUMEN
Objective To develop a double-wavelength HPLC method for the simultaneous determination of neogambogic acid,gambogic acid,( +)-catechin and L-epicatechin in Litong pill. Methods The quantitative analysis was carried out on C18 column(250 mm×4.6 mm,5 μm).A linear elution of methanol-acetonitrile(4: 1)and 0.2% phosphoric acid solution was adopted at the flow rate of 1.1 mL·min-1 ,with the detection wavelength set at 360 nm for neogambogic acid and gambogic acid,and at 280 nm for(+)-catechin and L-epicatechin. Results The linear ranges of neogambogic acid,gambogic acid,(+)-catechin and L-epicatechin were 5.85-117.00 μg·mL-1(r= 0.999 5),8.95-179.00 μg·mL-1(r= 0.999 8),6.90-138.00 μg·mL-1(r= 0.999 7),and 5.30-106.00 μg·mL-1(r = 0.999 9),respectively.The average recoveries were 97.82%(RSD= 1.21%),98.72%(RSD = 1.30%),96.96%(RSD = 0.84%)and 99.26%( RSD = 1.46%)for neogambogic acid, gambogic acid,(+)-catechin and L-epicatechin,respectively. Conclusion The method is simple,accurate,reproducible and may be used for the simultaneous determination of neogambogic acid,gambogic acid,(+)-catechin and L-epicatechin in Litong pill.