Automatic Time-Resolved Fluorescence Immunoassay of Serum Alpha Fetoprotein-L3 Variant via LCA Magnetic Cationic Polymeric Liposomes Improves the Diagnostic Accuracy of Liver Cancer

PURPOSE: The aim of this study was to develop an avidin-modified macromolecular lipid magnetic sphere and its application in differential diagnosis of liver disease and liver cancer. MATERIALS AND METHODS: Lectin-modified macromolecular lipid magnetic spheres were prepared by thin-film hydration method using lentil lectin derivatives (LCA-HQ) and cholesterol as raw materials. Alpha-fetoprotein variants (AFP-L3) in serum from healthy people, liver disease and liver cancer patients were isolated using the prepared lectin-modified macromolecular lipid magnetic spheres, and alpha-fetoprotein (AFP) and AFP-L3 were detected by fully automatic time-resolved fluorescence immunoassay. RESULTS: The lectin polymer lipid magnetic sphere prepared in this study was superparamagnetic and encapsulated by a lectin derivative. There was no significant difference in the recovery rate of AFP-L3 between avidin magnetic ball-automatic time-resolved fluorescence immunoassay and manual micro-affinity column method (p>0.05). We found that AFP-L3 can be used as a differential indicator between liver cancer and liver disease. The positive rate of AFP and AFP-L3 in liver cancer patients was higher than that in healthy people and liver disease patients (p<0.001). The AUC (95% CI) of AFP and AFP-L3 were 0.743 ± 0.031 and 0.850 ± 0.024, respectively. AFP-L3 AUC value is greater than AFP; therefore, AFP-L3 distinguishes liver cancer more accurately, and the difference is statistically different, p<0.05. CONCLUSION: We proposed a novel method for integration of the lectin polymer lipid magnetic spheres and time-resolved fluorescence immunoassay that enables simple, accurate and rapid determination of AFP-L3 in clinical samples. To be noted, fully automatic time-resolved fluorescence immunoassay compared with the commonly used techniques in clinical practice, the measurement procedure is simple and is expected to be used for the detection and accurate diagnosis of liver cancer.