As the thyroxine (T4) precisely reflects the thyroid dysfunction for ourself, it becomes one of the most important indicators for patients to analyze the thyroid status. However, common methods for detecting T4 still contain an essential issue that natural T4 converts to biologically
active triiodothyronine and influences the result unpredictable. In this study, a new T4 protein was synthesized and applied on a thyroxine-labeled alkaline phosphatase chemiluminescence immunoassay for detection of thyroxine hormone. Under the optimal conditions, the applied immunoassay shows
a great linear range from 5 ng/mL to 300 ng/mL and exhibits comparable stability (12 months), sensitivity (1.01 ng/mL), and specificity (>0.5 ng/mL) compared with natural T4. Thus, the proposed new thyroxine-labeled alkaline phosphatase chemiluminescence immunoassay offers a better method
to synthesis thyroxine and shows a potential in promoting the stability and sensitivity for thyroxine In-Vitro diagnosis.