Recent advance on magnetic-luminescent bifunctional nano-beads: composite strategies and versatile analysis...

Luminescence-based analytical methods have attracted considerable attention due to the fascinating merits of high sensitivity, affordability, and quick screening. However, autofluorescence and scattered light caused by the excitation of ultraviolet (UV) or blue light result in low ratio of signal to noise (S/N) or sensitivity. The adoption of diverse phosphors with unique characters e.g. near-infrared (NIR) excitation or emission, time-resolution has partially resolved the above shortcomings, but matrix effects are still critical. The introduction of magnetic separation is an ideal and promising solution. Magnetic-luminescence bifunctional nano-beads have achieved great advancement both in probe design and construction, and versatile assay applications, but are rarely summarized and discussed. Herein, in this review, we systematically summarize recent research progress on the synthesis methodologies of magnetic-luminescence bifunctional probes, and their applications in detection and testing. We first classify their fabrications strategies, meanwhile, and the corresponding merits and drawbacks are discussed objectively. Their various applications in lateral flow immunoassay (LFIA), fluorescent encoding, molecular imprinting, metal ion detection, and biomedical imaging are summarized and discussed. Finally, the challenges and future possibilities of magnetic-luminescence nano-beads are proposed, and we hope that it will bring some inspirations to the relevant researchers.