The preliminary evaluation of RIA Kit of plasma MNs

Objective: The performance of the self-developed radioimmunoassay kit for MNs obtained. The contents of methoxy-adrenaline (MN) and methoxy-noradrenaline (NMN) in plasma were detected by RIA kit and LC-MS/MS, respectively. The correlation and consistency between the two methods were investigated, and the precision, recovery and sensitivity of RIA kit were analyzed. Results: The correlation coefficients r² were 0.97 and 0.98, and the consistencies were 100% and 86%, respectively. The intra-and inter-assay differences of MNS RIA kits were less than 15%, the recovery of MN was 89%-103%, and the recovery of NMN was 97%-119%. The detection limit of MN was 4.3 pg/mL, and the detection limit of NMN was 19.8 pg/mL. Conclusion: The self-developed plasma MNS radioimmunoassay kit has high precision and accuracy, and has good correlation and consistency with LC-MS/MS. It is expected to replace LC-MS/MS as a routine method for qualitative diagnosis of PPGL. (authors)