title: Magnetic-field-assisted rapid ultrasensitive immunoassays using Fe3O4/ZnO/Au nanorices as Raman probes.
abstract: Rapid and ultrasensitive immunoassays were developed by using biofunctional Fe3O4/ZnO/Au nanorices as Raman probes. Taking advantage of the superparamagnetic property of the nanorices, the labeled proteins can rapidly be separated and purified with a commercial permanent magnet. The unsusceptible multiphonon resonant Raman scattering of the nanorices provided a characteristic spectroscopic fingerprint function, which allowed an accurate detection of the analyte. High specificity and selectivity of the assay were demonstrated. It was found that the diffusion barriers and the boundary layer effects had a great influence on the detection limit. Manipulation of the nanorice probes using an external magnetic field can enhance the assay sensitivity by several orders of magnitude, and reduce the detection time from 1 h to 3 min. This magnetic-field-assisted rapid and ultrasensitive immunoassay based on the resonant Raman scatting of semiconductor shows significant value for potential applications in biomedicine, food safety, and environmental defence.
authors.affiliation: Centre for Advanced Optoelectronic Functional Materials Research, Key Laboratory for UV Light-Emitting Materials and Technology of Ministry of Education, Northeast Normal University, Changchun 130024, PR China.
authors.forename: Xia
authors.initials: X
authors.lastname: Hong
authors.forename: Xueying
authors.initials: X
authors.lastname: Chu
authors.forename: Peng
authors.initials: P
authors.lastname: Zou
authors.forename: Yichun
authors.initials: Y
authors.lastname: Liu
authors.forename: Guoliang
authors.initials: G
authors.lastname: Yang
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D004574:Electromagnetic Fields; D004867:Equipment Design; D019544:Equipment Failure Analysis; D007118:Immunoassay / Q000295:instrumentation*; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000295:instrumentation*; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D058185:Magnetite Nanoparticles; D015034:Zinc Oxide