Establishment,methodological Evaluation And Clinical Application Of Reference Method For The Measurement Of Catalytic Concentration Of Alanine Aminotransferase

Objective:Establish a reference method for the measurement of catalytic concentration of alanine aminotransferase,and evaluate the methodology of the established reference method to explore the application of reference method in clinical.Methods:To establish the reference method for the measurement of catalytic concentration of alanine aminotransferase(ALT)according to IFCC primary reference procedure for the measurement of catalytic concentration of ALT,and improve experimental conditions to establish ALT reference method in our room.We are guided by the NCCLS documents(EP15-A?EP5-A2?EP6-A)to evaluate the precision,accuracy,and linear range of the standard operation procedure for the measurement of catalytic concentration of ALT.The established reference method was compared with the clinical routine detection system of Beckman DxC 800 to determine its clinical acceptability.Results:1.ShimadzuUV spectrophotometer,pH meter,pipette,volumetric flask,Shimadzu analytical balance,point thermometer are all qualified by Shanxi Provincial Quality Supervision Bureau.Optimization of reaction conditions:(1)The pipette aspirating mode is the best for the first gear and the second gear;(2)when the reaction temperature is stable at 37?,the temperature controller shows 36.9?;(3)In the case of incubation for 360s,the temperature inside the cuvette cup rises to 37?;(4)the accuracy of the absorbance at 340nm of the spectrophotometer,the low and high concentration of the standard materials are within the required uncertainty.2.After optimizing the reaction conditions,the methodological evaluation of the improved ALT reference method is carried out.The precision of the low-value and high-value batches is<1%,the total precision is<2%;Compared with Roche c.f.a.s multiple calibration liquid target values,within the uncertainty requirements;the upper limit of the ALT linear range is 330.4 U/L.3.Using the reference method to evaluate the Beckman DxC800 clinical routine detection system,the correlation was good(r~2=0.9998),and the relative bias between the two methods at the medical decision level was<1/2 CLIA'88.Conclusion:The ALT reference method has been basically established,and the precision,accuracy,and linear range all satisfy the requirements.The Beckman DxC 800automatic biochemical analyzer is compare to the reference method and the results can be accepted in clinic.