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Metal-organic frameworks (MOFs), a unique type of porous material characterized by high porosity, large internal surface area and remarkable structural tunability, have emerged as very attractive functional materials for a variety of applications. As a promising subclass of MOFs, lanthanide metal-organic frameworks (Ln-MOFs) integrate the unique advantages of MOFs and the intrinsic features of lanthanide ions, such as sharp emission bands, long luminescent lifetimes, large Stokes shifts, high color purity and high resistance to photobleaching. In this minireview, we provide a brief overview of the most recent advances in luminescent Ln-MOF nanoprobes, which covers from their chemical and physical fundamentals to bioapplications, including their synthetic strategies, optical properties and promising bioapplications in biodetection, bioimaging and therapy. Finally, some of the most important emerging trends and future efforts toward this rapidly evolving field are also envisioned.

The rapid emergence of drug-resistant bacteria has raised a great social concern together with the impetus for exploring advanced antibacterial ways. NIR-triggered antimicrobial photodynamic therapy (PDT) by lanthanide-doped upconversion nanoparticles (UCNP) as energy donor exhibits the advantages of high tissue penetration, broad antibacterial spectrum and less acquired resistance, but is still limited by its low efficacy. Now we designed a bio-inorganic nanohybrid and combined lysozyme (LYZ) with UCNP-PDT system to enhance the efficiency against resistant bacteria. Benefiting from the rapid adhesion to bacteria, intelligently bacteria-responsive LYZ release and synergistic LYZ-PDT effect, the nanoplatform achieves an exceptionally strong bactericidal capacity and conspicuous bacteriostasis on methicillin-resistant S. aureus. These findings pave the way for designing efficiently antibacterial nanomaterials and provide a new strategy for combating deep-tissue bacterial infection.

Near‐infrared (NIR) light, which has ignorable tissue scattering/absorption, minimal photodamage, and no autofluorescence interference, is highly favorable for bioapplications. NIR dye and lanthanide‐doped nanoparticle (LnNP), as representative NIR‐excited luminescence probes, have attracted increasing interest due to their unique optical property and low biological toxicity. Design of luminescence probes based on NIR dye/LnNP nanocomposites cannot only integrate the advantages but also achieve additional functions via regulating internal energy transfer pathways. In this review, we focus on the most recent advances in the development of NIR dye/LnNP nanocomposites as potential bioprobes, which cover from their fundamental photophysics to bioapplications, including energy transfer mechanisms, interface engineering (involving binding interaction, distance, and aggregation as key factors), and their applications for dye‐sensitized upconversion/downshifting luminescent bioimaging, detection of biomolecules, and NIR‐triggered diagnosis and therapy. Some future prospects and efforts toward this active research field are also envisioned.

Rattle structure is a topic of great interest in design and application of nanomaterials due to the unique core@void@shell architecture and the integration of functions. Herein, we developed a novel “ship-in-a-bottle” method to fabricate upconverting (UC) luminescent nanorattles by incorporating lanthanide-doped fluorides into hollow mesoporous silica. The size of nanorattles and the filling amount of fluorides can be well controlled. In addition, the modification of silica shell (with phenylene and amine groups) and the variation of efficient UC fluorides (NaYF4:Yb,Er, NaLuF4:Yb,Er, NaGdF4:Yb,Er and LiYF4:Yb,Er) were readily achieved. The resulting nanorattles exhibited a high capacity and pH-dependent release of the anti-cancer drug doxorubicin (DOX). Furthermore, we employed these nanorattles in proof-of-concept UC-monitoring drug release by utilizing the energy transfer process from UC fluorides to DOX, thus revealing the great potential of the nanorattles as efficient cancer theranostic agent.

A doubly interpenetrated microporous indium based metal–organic framework was solvothermally synthesized, in which cage-like pores and one-dimensional channels coexist. Due to its flexible nature, the complex exhibits a novel dynamic response to N2, Ar and CO2 sorption. Furthermore, the material shows a high H2 uptake capacity.

A polyhedral metal–organic framework (FJI-2) has been synthesized based on rare hexanuclear zinc clusters, which comprises 2.4 nm double-walled octahedral cages topologically featuring a new 3,12-connected structure. FJI-2 has a good H2 uptake capacity of 149.7 cm3 g−1 (1.34 wt %) at 77 K and 1.0 bar, and the IAST calculation predicts highly selective adsorption of CO2 over N2 and CH4.