Methodological evaluation on serum free light chains detected by immunoturbidimetry / 国际检验医学杂志

ABSTRACT

Objective To perform the methodological evaluation on Beckman Immage 800 automatic special protein analyzer for determining serum freeκ,λlight chains (sFLC) .Methods The Beckman Immage800 automatic special protein analyzer was used to quantitatively detect sFLC values for investigating its precision and accuracy ,analyzing its detecting range ,interference and residual contamination rate ,meanwhile verifying its reference intervals .Results The low and high values of within‐run precision coefficients of variation(CV) forκsFLC were 7 .84% and 2 .95% respectively ;which of between‐run precision CV were 7 .38% and 5 .57% re‐spectively .The within‐run precision CV for λFLC were 4 .59% and 3 .94% respectively ,which of between‐run precision CV were 3 .97% and 2 .01% respectively ;bias for detecting theκFLC andλFLC fixed quality serum and the target values was less than 5% , when the analytical detection ranges of κFLC andλFLC were 10 .8-128 .0 mg/L and 10 .1-121 .0 mg/L ,a value was 0 .95-1 .05 , r2 ≥0 .98;the carry‐over rates of κFLC andλFLC were 0 .411% and 0 .216% respectively .The interference test results showed that when free hemoglobin≤342 .0 μmol/L ,conjugated bilirubin ≤342 .0 μmol/L ,hemoglobin≤5 g/L and chyle ≤2 400 turbidness , which had no influence on sFLC results ;among 40 healthy subjects undergoing the physical examination ,1 case of κFLC detection results exceeded the reference interval recommended by the manufacturer ,while theλFLC detection values in these 40 cases were all within the reference interval recommended by the manufacturer .Conclusion The main analytical performance of the Beckman Im‐mage800 automatic special protein analyzer for detecting sFLC meets the requirements of quality objectives and can provides the sci‐entific and precise evidence of diagnosis and treatment for clinic .