Objective To verify and preliminarily apply the ELISA method for determination of human coagulation factor Ⅺ(F Ⅺ) residues in high concentration(10%) human immunoglobulin for intravenous injection(IVIG),so as to monitor the content of FⅪ in process samples.Methods The dilution reliability,accuracy,precision,limit of quantitation precision,linearity and range,and durability of the ELISA method for determination of FⅪ residues in 10% IVIG were verified.The FⅪ residues in three batches of 10% IVIG in the preparation process samples and the final products were determined by the verified method,and the results of the final products were compared with those of the commercially available IVIG(pH 4).Results Matrix effect existed in the determination of FXI residues in 10% IVIG by using this method,which could be solved by diluting 5-80 times.The average spike recovery rate of verification for accuracy was 100.1%.The relative standard deviations(RSDs) of repeatability verification by two experimenters were 8.54% and 5.70%,respectively,and the RSD of intermediate precision verification was 7.13%.The limit of quantitation concentration was 0.05 ng/mL,and the RSDs of limit of quantitation repeatability verification by two experimenters were 6.39% and 3.77%,respectively,and the RSD of intermediate precision verification was 12.00%.There was a good linear relationship between the concentration of F Ⅺ and A_(450) in the range of 0.01-5.00 ng/mL(r=0.999 9).Durability verification showed that different incubation time and 15 d storage under the specified conditions after opening the kit had no effect on F Ⅺ detection.The octanoic acid precipitation process removed F Ⅺ from 10% IVIG stably and effectively,and the residual amount of F Ⅺ in the three batches of 10% IVIG was lower than that in the commercially available IVIG(pH 4).Conclusion The method has good accuracy,precision and durability,and can satisfy the determination of FⅪ residues in 10% IVIG in laboratory.

【Objective】 To establish an enzyme-linked immunosorbent assay (ELISA) method for the determination of residual human coagulation factor Ⅺ in human prothrombin complex and validate the method. 【Methods】 Human factor Ⅺ was reacted with the capture antibody coated on the microtiter plate. After appropriate washing steps, biotinylated primary antibody was bound to the captured protein. Excess primary antibody was washed away and bound antibody was reacted with horseradish peroxidase conjugated streptavidin. TMB substrate was used for color development at 450 nm. The dilution reliability, accuracy, specificity, repeatability, intermediate precision, linearity, range and durability were verified. 【Results】 The verification results showed that the accuracy and specificity of this method met the experimental requirements, with an average recovery rate of 109.2% and RSD of 6.93%. The repeatability RSD was 6.78%, and the intermediate precision RSD was 6.75%, indicating good precision. The linear regression correlation coefficient of standard curve was 0.999 9, showing good accuracy and precision within the linear range. The durability was verified by the incubation time and the validity period of reagent kit opening. The results showed that the RSD of the incubation time change was 6.62%, indicating that the incubation time of this detection method was controlled between 28 to 32 minutes, and there was no significant impact on the results. The RSD of the detection results before and after the reagent kit was opened and stored under conditions for 7 days was 3.84%, indicating that the preservation of the reagent kit according to the conditions for 7 days after opening has no effect on the FⅪ detection results. Both indicated that the method had good durability. The dilution reliability results showed that there was a "hook" effect in the detection of FⅪ residue in human prothrombin complex, which could be solved by diluting 100 to 200 times. 【Conclusion】 This method can be used for the determination of FⅪ residues of human prothrombin complex in laboratory.