Facile synthesis of Fe3O4@polyethylenimine with peroxidase-like activity for highly sensitive detection of interferon α-2b简易方法合成具有类过氧化物酶活性的聚乙烯亚胺包覆的四氧化三铁用于高灵敏检测干扰素α-2b

The sensitive detection of interferon alpha-2b (IFN-α2b) is crucial in treating viral infections and cancers. However, the natural enzymes used in the traditional enzyme-linked immunosorbent assays (ELISA) face the obstacles of high cost and low stability. Therefore, there is an urgent need to develop more cost-effective and stable alternatives to detect IFN-α2b. To address this issue, we synthesized poly-ethyleneimine (PEI)-modified magnetic nanoparticles (Fe3O4@PEI MNPs) that are highly stable, affordable and simple to prepare. These Fe3O4@PEI MNPs serve as a substitute for horseradish peroxidase in the ELISA-based detection of IFN-α2b, providing better sensitivity than chromatographic and traditional ELISA techniques. The peroxidase-like activity of Fe3O4@PEI MNPs can develop color, enabling the visualization of IFN-α2b. The proposed immunoassay has a linear increase with IFN-α2b concentrations ranging from 0.075 to 25 ng mL−1, with a low limit of detection of 0.055 ng mL−1. Based on the outstanding peroxidase-like activity of Fe3O4@PEI MNPs, this method has the potential to be used for the clinical detection of IFN-α2b and other protein biomarkers in disease diagnosis and treatments.