Performance evaluation of paramagnetic particles chemiluminescence micro-particle immunoassay for determination of serum vitamin B_(12)

Objective: To evaluate the performance of paramagnetic particles chemiluminescence microparticle immunoassay( CMIA) for detection of serum Vitamin B12( VitB12). Methods: Analysed CMIA system precision,accuracy,anti-interference,analytical measuring range( AMR),clinical reportable range( CRR) and biological reference interval were evaluated,according to the clinical and laboratory standards institude( CLSI) EP5-A2,EP15-A2,EP7-A2,EP6-A,C28-A3 c guidelines. To assess the accuracy,we used the reference material SRM 1955 from national institute of standards and technology( NIST) and external quality assessment( EQA)samples( LN5-B and K-C) from CAP. Results: The precisions of within-run and between-run were less than standard of manufacturer when the concentration of VitB12 was 108. 84-874. 43 pmol /L. The results of SRM1955 met the allowable range of the target value. The results of EQA samples( K-C and LN5-B) also up to the CAP calibration and validation /linear evaluation error limits stipulated standards,and the results through linear verification when the concentration of VitB12 was 89- 1 057 pmol /L. The 95% verification interval contains the specified value also. The relative deviation was less than external quality assessment standard from national center for clinical laboratory( TEa: target value ± 25%). Anti-interference evaluation showed without significant interferenc when TG ≤ 20 mmol /L,Bil ≤ 300 μmol /L VitC ≤ 1. 5 g /L to the VitB12 detection system( CMIA). AMR validation showed determines the best fit equation was linear equation polynomial. There was the linear relationship when the concentration of VitB12 was 0- 1 107 pmol /L. The upper limit of CRR was 110 700 pmol /L,the maximum dilution was 100 times. Biological reference interval validation showed that the overall level of VitB12 in this study reference individuals conform to the standard of manufacturer statement for the population,the overall level of VitB12 in female little higher than male,but no significant differences. Conclusion: Performance of CMIA for detection of serum VitB12 basically met needs of laboratory,which can provide reliable results of VitB12 for laboratory,provide information for the VitB12 status of population in the laboratory evaluation.