Nanoparticles made of metal-organic frameworks (nanoMOFs) are becoming of increasing interest as drug carriers. However, preventing nanoMOFs recognition and clearance by the innate immune system, a prerequisite for biomedical applications, presents an important challenge. In this study we provide a proof of concept that the outer surface of biocompatible iron-based nanoMOFs can be functionalized in a rapid, organic solvent-free and non-covalent manner using a novel family of comb-like copolymers made of dextran (DEX) grafted with both poly(ethylene glycol) (PEG) and alendronate (ALN) moieties. We describe the synthesis and full characterization of DEX-PEG-ALN copolymers by click chemistry, with control of both the amount of grafted PEG and ALN moieties. The copolymers, freely soluble in aqueous media, were used to directly coat the nanoMOFs in water by simple incubation at room temperature. The coating procedure did not affect the nanoMOFs' morphology nor their crystalline structure. As strong iron complexing groups, the ALN moieties ensured multiple cooperative anchoring of the copolymers to the nanoMOFs surface, resulting in stable coatings that substantially decreased their internalization by macrophages in vitro, providing new perspectives for biomedical applications.

Hybrid porous nanoscale metal organic frameworks (nanoMOFs) made of iron trimesate are attracting increasing interest as drug carriers, due to their high drug loading capacity, biodegradability, and biocompatibility. NanoMOF surface modification to prevent clearance by the innate immune system remains still challenging in reason of their high porosity and biodegradable character. Herein, FDA-approved lipids and poly(ethylene glycol) (PEG)-lipid conjugates were used to engineer the surface of nanoMOFs by a rapid and convenient solvent-exchange deposition method. The resulting lipid-coated nanoMOFs were extensively characterized. For the first time, we show that nanoMOF surface modification with lipids affords a better control over drug release and their degradation in biological media. Moreover, when loaded with the anticancer drug Gem-MP (Gemcitabine-monophosphate), iron trimesate nanoMOFs acted as "Trojan horses" carrying the drug inside cancer cells to eradicate them. Most interestingly, the PEG-coated nanoMOFs escaped the capture by macrophages. In a nutshell, versatile PEG-based lipid shells control cell interactions and open perspectives for drug targeting.

A highly practical method for the synthesis of 2-aminobenzothiazoles has been developed through an iron-catalyzed tandem reaction. The present tandem process allows the assembly of a wide range of 2-aminobenzothiazoles by the reactions of 2-halobenzenamines with isothiocyanates.

Nanomedicine recently emerged as a novel strategy to improve the performance of radiotherapy. Herein we report the first application of radioenhancers made of nanoscale metal‐organic frameworks (nanoMOFs), loaded with gemcitabine monophosphate (Gem‐MP), a radiosensitizing anticancer drug. Iron trimesate nanoMOFs possess a regular porous structure with oxocentered Fe trimers separated by around 5 Å (trimesate linkers). This porosity is favorable to diffuse the electrons emitted from nanoMOFs due to activation by γ radiation, leading to water radiolysis and generation of hydroxyl radicals which create nanoscale damages in cancer cells. Moreover, nanoMOFs act as “Trojan horses”, carrying their Gem‐MP cargo inside cancer cells to interfere with DNA repair. By displaying different mechanisms of action, both nanoMOFs and incorporated Gem‐MP contribute to improve radiation efficacy. The radiation enhancement factor of Gem‐MP loaded nanoMOFs reaches 1.8, one of the highest values ever reported. These results pave the way toward the design of engineered nanoparticles in which each component plays a role in cancer treatment by radiotherapy.

Recently developed, nanoscale metal-organic frameworks (nanoMOFs) functionalized with versatile coatings are drawing special attention in the nanomedicine field. Here we show the preparation of core–shell MIL-100(Al) nanoMOFs for the delivery of the anticancer drug doxorubicin (DOX). DOX was efficiently incorporated in the MOFs and was released in a progressive manner, depending on the initial loading. Besides, the coatings were made of biodegradable γ-cyclodextrin-citrate oligomers (CD-CO) with affinity for both DOX and the MOF cores. DOX was incorporated and released faster due to its affinity for the coating material. A set of complementary solid state nuclear magnetic resonance (ssNMR) experiments including 1H-1H and 13C-27Al two-dimensional NMR, was used to gain a deep understanding on the multiple interactions involved in the MIL-100(Al) core–shell system. To do so, 13C-labelled shells were synthesized. This study paves the way towards a methodology to assess the nanoMOF component localization at a molecular scale and to investigate the nanoMOF physicochemical properties, which play a main role on their biological applications.

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