Abstract:

Objective To evaluate the performance of serum S100B determination kit based on electro-chemiluminescence immunoassay,and to investigate preliminarily the correlation between serum S100B concentration and the severity of blood-brain barrier injury. Methods The precision was validated according to the Clinical and Laboratory Standards Institute （CLSI） EP-15A protocols. Linearity and accuracy were also validated. A total of 45 patients with blood-brain barrier injury were enrolled. Serum S100B concentrations were determined. The patients were classified into 4 groups according to quotient albumin（QALB）results [<the first quartile（P₂₅）,P₂₅-<the second quartile（P₅₀）,P₅₀-<the third quartile（P₇₅） and ≥P₇₅] ,<P₂₅（low QALB group,11 cases）,P₂₅-<P₅₀ （middle QALB group,11 cases）,P₅₀-<P₇₅ （high QALB group,11 cases） and ≥P₇₅（extremely high QALB group,12 cases）. The correlation between S100B and the severity of blood-brain barrier injury was observed. Results The within-run coefficients of variations（CV） of 3 concentrations （S1 = 0.05 µg/L,S2 = 0.12 µg/L and S3 = 2.75 µg/L）were 5.08%,3.00% and 5.23%,and the between-run CV were 5.07%,3.27% and 5.46%, respectively. Relative biases were 5.26% and 0.41%,respectively. The linear range was 0.01-36.00μg/L, which indicating a satisfied linearity （Y = 0.999X + 0.003,R²= 0.999）. The S100B concentration in low QALB group was significantly lower than that in extremely high QALB group （P = 0.04）,and there was no statistical significance between the other 2 groups（P > 0.05). Conclusions Serum S100B determination kit based on electro-chemiluminescence immunoassay exhibits satisfied clinical performance,which is suitable for current clinical application. Serum S100B concentration could reflect the severity of blood-brain barrier injury,and assist clinicians to evaluate the disease status for patients.

Key words: S100B, Blood-brain barrier, Performance assessment