Gelothermal Synthesis of Monodisperse MIL‐88A Nanoparticles with Tunable Sizes and Metal Centers for Potential Bioapplications

Abstract

Developing novel synthetic strategies to downsize metal‐organic frameworks (MOFs) from polydisperse crystals to monodisperse nanoparticles is of great importance for their potential bioapplications. In this work, a novel synthetic strategy termed gelothermal synthesis is proposed, in which coordination polymer gel is first prepared and followed by a thermal reaction to give the monodisperse MOF nanoparticles. This novel synthetic strategy successfully leads to the isolation of Materials of Institute Lavoisier (MIL‐88), Cu(II)‐fumarate MOFs (CufumDMF), and Zeolitic Imidazolate Frameworks (ZIF‐8) nanoparticles. Focused on MIL‐88A, the studies reveal that the size can be well‐tuned from nanoscale to microscale without significant changes in polydispersity index (PDI) even in the case of in situ metal substitution. A possible mechanism is consequently proposed based on extensive studies on the gelothermal condition including sol‐gel chemistry, thermal condition, kinds of solvents, and so on. The unique advantages of monodisperse MIL‐88A nanoparticles over polydisperse ones are further demonstrated in terms of in vitro magnetic resonance imaging (MRI), cellular uptake, and drug‐carrying properties.

Mesoporous carbon hemispheres integrated with Fe–Gd nanoparticles for potential MR/PA imaging-guided photothermal therapy

“…Since the calculated ratio of r 2 / r 1 is about 22.13, larger than 10, Fe–Gd/CHS could be regarded as a T 2 contrast agent. 49–56 PAI was then assessed in an aqueous solution. As shown in Fig.…”

Er3+-Sensitized Upconversion/Down-Shifting Luminescence in Metal–Organic Frameworks

“…1,2 The multiple coordination modes formed by different metal ions/clusters and multifunctional ligands determine an almost infinite number of possible structures and compositions of MOFs. 3 With diverse structures and the unique advantages of large surface area and tunable pore size, MOFs have been widely utilized in the fields of catalysis, 4 gas separation, 5 drugcarrying, 6 fluorescence imaging, 7,8 and biological and chemical analysis. 9,10 Compared with transition metal ions, the lanthanide ions have higher coordination numbers and rich coordination geometries.…”

“…Metal–organic frameworks (MOFs) are a category of inorganic–organic hybrid materials with periodic network structure formed by self-assembly of inorganic nodes (metal atoms or metal clusters) and bridging organic ligands. , The multiple coordination modes formed by different metal ions/clusters and multifunctional ligands determine an almost infinite number of possible structures and compositions of MOFs . With diverse structures and the unique advantages of large surface area and tunable pore size, MOFs have been widely utilized in the fields of catalysis, gas separation, drug-carrying, fluorescence imaging, , and biological and chemical analysis. , …”