Au-Loaded Superparamagnetic Mesoporous Bimetallic CoFeB Nanovehicles for Sensitive Autoantibody Detection

Abstract

Construction of a well-defined mesoporous nanostructure is crucial for applying nonnoble metals in catalysis and biomedicine owing to their highly exposed active sites and accessible surfaces. However, it remains a great challenge to controllably synthesize superparamagnetic CoFebased mesoporous nanospheres with tunable compositions and exposed large pores, which are sought for immobilization or adsorption of guest molecules for magnetic capture, isolation, preconcentration, and purification. Herein, a facile assembly strategy of a block copolymer was developed to fabricate a mesoporous CoFeB amorphous alloy with abundant metallic Co/Fe atoms, which served as an ideal scaffold for well-dispersed loading of Au nanoparticles (∼3.1 nm) via the galvanic replacement reaction. The prepared Au−CoFeB possessed high saturation magnetization as well as uniform and large open mesopores (∼12.5 nm), which provided ample accessibility to biomolecules, such as nucleic acids, enzymes, proteins, and antibodies. Through this distinctive combination of superparamagnetism (CoFeB) and biofavorability (Au), the resulting Au− CoFeB was employed as a dispersible nanovehicle for the direct capture and isolation of p53 autoantibody from serum samples. Highly sensitive detection of the autoantibody was achieved with a limit of detection of 0.006 U/mL, which was 50 times lower than that of the conventional p53-ELISA kit-based detection system. Our assay is capable of quantifying differential expression patterns for detecting p53 autoantibodies in ovarian cancer patients. This assay provides a rapid, inexpensive, and portable platform with the potential to detect a wide range of clinically relevant protein biomarkers.

Bimetallic MoO3/Ni-N-C Nanoalloys Derived from MOFs for Electrocatalytic Urea Oxidation Reaction

“…Nowadays, metal–organic frameworks (MOFs) are considered the most promising electrocatalysts and have received a lot of attention as precursors to prepare electrocatalysts with thermal decomposition, high specific surface area, tunable structural properties, and abundant catalytic molecular units. Compared with conventional MOF-based precursors, when MOFs are heated at high temperatures, they not only retain their original structural features of the precursors, but metal active centers are transformed into metal nanocrystals dispersed in the specific carbon framework of the MOFs at high temperatures, which is very promising for controlling the structure of the derived catalysts and applying in fields such as gas sensing and energy catalysis. − However, not all MOF-derived materials have good catalytic properties, and the catalytic performance can be improved by adding other metal elements in the MOF precursors to modulate their electronic structure, or by further modifying the MOF-derived materials to enhance their catalytic activity …”

Harmonious Heterointerfaces Formed on 2D‐Pt Nanodendrites by Facet‐Respective Stepwise Metal Deposition for Enhanced Hydrogen Evolution Reaction

“…Because heterogeneous catalysis is a surface‐limited process, catalytic reactions on nanocrystals (NCs) are jointly determined by the surface characteristics of exposed facets [1–3] . The facets could be further subjected to morphology adjustment, composition engineering, and defect creation descending more accustomed catalytic performance as benefitted by the adjusted electronic structures and regulated energetics to the reaction species [4–10] . Particularly, different types of active sites in a hybrid can synergistically facilitate catalysis.…”

“…[1][2][3] The facets could be further subjected to morphology adjustment, composition engineering, and defect creation descending more accustomed catalytic performance as benefitted by the adjusted electronic structures and regulated energetics to the reaction species. [4][5][6][7][8][9][10] Particularly, different types of active sites in a hybrid can synergistically facilitate catalysis. However, because of the natural facet-dependent properties of nanocatalysts, a deep understanding of the structureactivity relationship is required for choosing suitable nanocomponents according to their roles and characteristics for selective and useful modification of NC surfaces.…”

Size dependence of the surface spin disorder and surface anisotropy constant in ferrite nanoparticles

“…Decreasing the size of materials to the nanoscale, the effect of disorder becomes increasingly important. 3 Magnetic nanoparticles (NPs) promising technological and biomedical applications in for example, 4,5 magnetic recording, [6][7][8][9][10] magnetic uid hyperthermia, [11][12][13] magnetic manipulation for isolation of target biomolecules and rapid mixing, 14,15 and magnetic resonance imaging (MRI) 16,17 are due to their particular physical properties arising from their large surface-to-volume ratio. Different applications require distinct magnetic properties, for instance, data-storage applications demand high magnetic anisotropy to preserve thermal stability, 18 while magnetic hyperthermia and MRI necessitate superparamagnetic NPs.…”