Rearranging Fluorescence-Magneto Spatiality for “Win-Win” Dual Functions to Enhance Point-of-Care Diagnosis

Abstract

Fluorescent-magneto nanoemitters have gained considerable attention for their applications in mechanical controlling-assisted optical signaling. However, the incompatibility between magnetic and fluorescent components often leads to functional limitations in traditional magneto@fluorescence nanostructure. Herein, we introduce a new compact-discrete spatial arrangement on a “fluorescence@magneto” core–shell nanostructure consisting of a close-packed aggregation-induced emission luminogen (AIEgen) core and a discrete magnetic shell. This structural design effectively eliminates the optical and magnetic interferences between the dual components by facilitating AIEgens loading in core region and reducing the magnetic feeding amount through effective exposure of the magnetic units. Thereby, the resulting magneto-AIEgen nanoparticle (MANP) demonstrates “win-win” performances: (i) high fluorescent intensity contributed by AIEgens stacking-enhanced photoluminescence and reduced photons loss from the meager magnetic shell; (ii) marked magnetic activity due to magneto extraposition-minimized magnetic shielding. Accordingly, the dual functions-retained MANP provides a proof of concept for construction of an immunochromatographic sensing platform, where it enables bright fluorescent labeling after magnetically enriching and separating procalcitonin and lipoarabinomannan in clinical human serum and urine, respectively, for the clinical diagnosis of bacterial infections-caused inflammation and tuberculosis. This study not only inspires the rational design of magnetic-fluorescent nanoemitter, but also highlights promising potential in magneto-assisted point-of-care test and biomedicine applications.