Development of an ultrasensitive magnetic bead-based non-competitive chemiluminescent immunoassay for 17β-estradiol in milk

Chronic dietary intake of 17β-estradiol (E₂) poses significant health risks, necessitating rapid and accurate analytical techniques for effective surveillance. This study presents a magnetic particle (MP)-assisted non-competitive chemiluminescent immunoassay (NCLIA) designed for E₂ quantification in milk. The NCLIA employs anti-E₂ monoclonal antibody (mAb)-coated MPs to capture E₂ target molecules, followed by the recognition of acridinium ester (AE)-conjugated anti-E₂@mAb immunocomplex antibody. Magnetic separation facilitates efficient isolation of immunocomplexes before automated luminescence measurement. This NCLIA demonstrated superior performance, without the need for complex pretreatment of milk samples, significantly simplifying the analysis process. The detection limit was as low as 1.57 pg/mL, and total detection time was 8 min. Additionally, NCLIA’s results were highly consistent with those obtained by liquid chromatography-tandem mass spectrometry (LC–MS/MS), validating their reliability in analyzing real samples. Therefore, this study presents an efficient and reliable tool for the rapid screening and detection of 17β-estradiol in milk, which holds significant value for food safety monitoring.

Graphical abstract