Biomolecule-functionalized magnetic nanoparticles for flow-through quartz crystal microbalance immunoassay of aflatoxin B1.
A flow-through quartz crystal microbalance (QCM) immunoassay method has been developed based on aflatoxin B(1) antibody (anti-AFB(1))-functionalized magnetic core-shell Fe(3)O(4)/SiO(2) composite nanoparticles (bionanoparticles) in this study. To construct such an assay protocol, anti-AFB(1), as a model protein, was initially covalently immobilized onto the Fe(3)O(4)/SiO(2) surface, and then the functionalized nanoparticles were attached to the surface of the QCM probe with an external magnet. The binding of target molecules onto the immobilized antibodies decreased the sensor's resonant frequency, and the frequency shift was proportional to the AFB(1) concentration in the range of 0.3-7.0 ng/ml. The regeneration of the developed immunosensor was carried out via attaching or detaching the external magnet from the detection cell. In addition, the selectivity, reproducibility, and stability of the proposed immunoassay system were acceptable. Compared with the conventional ELISAs, the proposed immunoassay system was simple and rapid without multiple labeling and separation steps. Importantly, the proposed immunoassay method could be further developed for the immobilization of other antigens or biocompounds.
Wang
Li
L
School of Chemistry and Chemical Engineering, Yibin University, Yibin 644000, People's Republic of China. wanglitwp@163.com
Gan
Xian-Xue
XX
D016604:Aflatoxin B1 / Q000032:analysis* / Q000737:chemistry; D001672:Biocompatible Materials; D004797:Enzyme-Linked Immunosorbent Assay; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay / Q000295:instrumentation / Q000379:methods*; D007501:Iron / Q000737:chemistry; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D036103:Nanotechnology / Q000379:methods*; D011791:Quartz; D012825:Silicon / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared
D001672:Biocompatible Materials; D011791:Quartz; D012822:Silicon Dioxide; D016604:Aflatoxin B1; D007501:Iron; D052203:Ferrosoferric Oxide; D012825:Silicon