A rapid and sensitive sandwich assay for the detection of Alicyclobacillus acidoterrestris in apple juice based on magnetosome immunomagnetic separation combined with quantum dots immunoassay technology
Published:26 November 2024
DOI: 10.1016/j.foodchem.2024.142234
Jianrui Qi, Kai Wang, Tianli Yue
Abstract
The contamination of apple juice by Alicyclobacillus acidoterrestris (A. acidoterrestris) can cause significant economic losses. Therefore, developing a rapid and sensitive method for detecting A. acidoterrestris is necessary. To address this issue, this study prepared magnetosome–monoclonal antibodies immunomagnetic microspheres (IMMs) as capture probes to enrich A. acidoterrestris (IMMs-Aa) and monoclonal antibodies-quantum dots (mAb-CdTeQDs) as detection probes for detecting A. acidoterrestris. The obtained IMMs-Aa-mAb-CdTeQDs “sandwich” structure was used to detect A. acidoterrestris based on the fluorescence intensity. The strategy presented a good linear correlation (y?=?1048×?+?1891, R2?=?0.995) between the fluorescence intensity and the concentration of A. acidoterrestris (101–105?CFU/mL) with a low detection limit of 25.4?CFU/mL within 50?min. The recovery rate of this strategy in spiked apple juice ranged from 88.16?% to 107.03?%. Thus, this study established an efficient and highly sensitive magnetic capture-enrichment-separation-detection method for A. acidoterrestris.