OBJECTIVE To determine the concentration of 5-Fu in serum at seven time points from 8 Hepatic Cancer patients an by improved method of HPLC. METHODS HPLC-UV Determination was employed.Acetonitrile and iso-propanol were used as the extractive solvent.The mobile phase was methanol-acetonitrile-water(25∶5∶70), tetrabutylamino∶bromide was added.The wavelength for determination was 265 nm.RESULTS Good seperation and high recoveries (>91%) were obtained, without any interference from impurities of serum.Coeffi...