Objective To establish gas chromatog. for the determination of tri-Bu phosphate (TBP) residues in human prothrombin complex and then verify it.Methods Acid modified polyethylene glycol (PEG) (20 M) capillary column was used with n-hexane as solvent.The chromatog. parameters were as follows: gasification chamber temperature at 220°C, column temperature at 155°C, detector temperature at 220°C, column flow rate at 2.0 mL/min, carrier gas as N2, detector as FID, and collection time for 10 min.The accuracy, repeatability, linearity, specificity, intermediate precision, detection limit, quant. limit, range and durability were verified.Results The verification results showed that the method had good specificity.The linear regression correlation coefficient of standard curve was 0.99990.The recovery rate were 98.4%, 97.5%and 95.7%when the concentration at 50%, 100% (30 μg/mL) and 150%, resp., with an average recovery of 97.2% and a relative deviation of 2.15%.When the concentration was 100%, the repeatability was 2.08%, and the relative deviation of intermediate precision was 1.63%.The detection limit was 0.255 μg/mL, and the quant. limit was 0.511 μg/mL.After changing capillary chromatog. columns with different batch numbers but the same types and manufacturer, the applicability test of the system met the requirements, and the method had good durability.Conclusion This method can be used for the determination of TBP residues of human prothrombin complex in laboratory