Determination of Insulin-like Growth Factor I (IGF-I) in Serum by a Chemiluminescence Immunoassay (CLIA)

A high-performance chemiluminescence immunoassay (CLIA) has been established for the determination of insulin-like growth factor I (IGF-I) in human serum. This approach is dependent on a double antibody sandwich-complexation method to determine the concentration of IGF-I in serum. The results demonstrate that this method was able to determine IGF-I across a wide linear range from 5 to 1000 ng/mL. The limit of the blank was 0.022 ng/mL. The coefficient of variation (CV) was less than 7% for both intra-assay and inter-assay precision. The average recoveries were 109.4%, 98.8%, and 101.9%. This method offers excellent performance and provides a foundation for further clinical applications of serum IGF-I determination.