[Interference of Exogenous Insulin on Insulin Detection Test by Electrochemiluminescence Immunoassay]

Objective: To explore the interference of exogenous insulin therapy on insulin detection test by electrochemical luminescence immunoassay (ECLIA).

Methods: Insulin level was determined by ECLIA. According to the requirements of EP7-A2 of American Society for Clinical Laboratory Standards Institute Standards, paired difference experiment was conducted to evaluate the interference of 8 kinds of exogenous insulin on insulin detection, dose effect experiment was conducted to determine the relationship between exogenous insulin concentration and interference degree.

Results: When the interfering substance concentrations were ≤250 μU/mL, Gansulin N^Ⓡ, Gansulin R^Ⓡ, Humulin R^Ⓡ,Novolin R^Ⓡ and Lantus^Ⓡ all showed linear positive interference, while Levemir^Ⓡ showed a linear negative interference in high concentrations insulin and non-interfering in low concentrations insulin, Humalog^Ⓡ and Novo Rapid^Ⓡ showed non-interference in insulin detection.

Conclusions: The use of different exogenous insulin may have different interference on insulin measurement, which need laboratorians and physicians notice to avoid misdiagnosis.