Comparative study of serum folate detection using improved microbial assay and electrochemiluminescence method
Objective To compare improved microbial assay(IMA)and electrochemiluminescence(ECL)for measuring serum folate,and to investigate the linear or non-linear correlation between the results of the two methods.Methods This comparative study was conducted in National Health Commission Key Laboratory of Reproductive Health from October 2020 to February 2021,in which the folate concentration of 251 serum samples were measured by IMA and ECL.According to the serum folate concentration,the folate status was divided into sufficient(≥13.5 nmol/L),marginal deficiency(6.8≤serum folate＜13.5 nmol/L),and deficiency(＜6.8 nmol/L).Pearson correlation analysis and multivariate fractional polynomial(MFP)model were used to evaluate the correlation between the results measured by the two methods.The sensitivity of ECL for detecting folate status were calculated based on the IMA results as the golden standard.Results The average folate concentrations in serum samples measured by ECL and IMA were(19.8±8.2)nmol/L and(23.0±9.7)nmol/L,respectively(P＜0.001).The Pearson correlation coefficient(r)of the two methods was 0.894(P＜0.001),yet the MFP model demonstrated non-linear correlation between the two methods.When the IMA results were≤9.1 nmol/L,the r was 0.070(P＞0.05);when the IMA results were＞9.1 nmol/L,the r was 0.867(P＜0.001);for non-hemolytic serum samples(n=221),the r was 0.902(P＜0.001).Additionally,the sensitivity of ECL detecting folate deficiency was 27.78％,and the sensitivity of ECL detecting folate insufficiency(deficiency and marginal deficiency)was 93.33％.Conclusion When folate concentrations was＞9.1 nmol/L),the results of ECL and IMA were highly correlated;yet the correlation between the two methods was weak at lower folate concentrations,indicating that ECL was not applicable for serum folate measurement among folate insufficiency population.
Folic acidSerumImproved microbial assayElectrochemiluminescenceComparative study
万方数据
维普
