A Three-Dimensional Metal-Organic Framework with an Unprecedented Octahedral Building Unit

Nanoscale MOFs: From synthesis to drug delivery and theranostics applications

Since the first report in 1989, Metal-Organic Frameworks (MOFs) self-assembled from metal ions or clusters, as well as organic linkers, have attracted extensive attention. Due to their flexible composition, large surface areas, modifiable surface properties, and their degradability, there has been an exponential increase in the study of MOFs materials, specifically in drug delivery system areas such as infection, diabetes, pulmonary disease, ocular disease, imaging, tumor therapy, and especially cancer theranostics. In this review, we discuss the trends in MOFs biosafety, from "green" synthesis to applications in drug delivery systems. Firstly, we present the different "green" synthesis approaches used to prepare MOFs materials. Secondly, we detail the methods for the functional coating, either through grafting targeting units, poly(ethylene glycol) (PEG) chains or by using cell membranes. Then, we discuss drug encapsulation strategies, host-guest interactions, as well as drug release mechanisms. Lastly, we report on the drug delivery applications of nanoscale MOFs. In particular, we discuss MOFs-based imaging techniques, including magnetic resonance imaging (MRI), photoacoustic imaging (PAI), positron emission tomography (PET), and fluorescence imaging. MOFs-based cancer therapy methods are also presented, such as photothermal therapy (PTT), photodynamic therapy (PDT), radiotherapy (RT), chemotherapy, and immunotherapy.

A porous metal-organic framework based on Zn6O2 clusters: chemical stability, gas adsorption properties and solvatochromic behavior

A highly connected 3D metal-organic framework with tfz-d topology based on Zn(6)O(2) clusters and flexible carboxylate ligands has been synthesized. The obtained Zn-MOF shows solvatochromic behavior for fluorescence sensing of small molecules, gas adsorption properties and exceptional chemical stability and might have applications for separation and detection purposes.

Rational Design of MOFs Constructed from Modified Aromatic Amino Acids

Three Phe and Tyr derivatives, 2-amino-3-(4-aminophenyl)-propionic acid (AAP), 3E-[5-(2-amino-2-carboxyethyl)-2-methoxyphenyl]-acrylic acid (AMPA) and 3-(4-aminophenyl)-2-(carboxymethyl-amino)-propionic acid (ACP) have been chosen as the ligands to construct four kinds of novel metal-organic frameworks (MOFs) (five structures). These structures are, [Cd(II){(R)-AAP}(Py)(H(2)O)](ClO(4)), (R)-1; [Cd(II){(S)-AAP}(H(2)O)(2)](ClO(4)), (S)-2; [Zn(2) (II){(R,S)-AMPA}(H(2)O)], (R,S)-3; [Zn(2) (II){(R)-ACP}(Py)(3)](ClO(4))(2), (R)-4; and the inversion twin of (R)-1. Rational design to adjust the "depth" and the "width" of ligands can mediate the size and the shape of the grids of these 2D layers. Additionally, among these compounds, three pure chiral coordination polymers are obtained, owing to the inducement of chirality by the modified amino acids. This property makes them potential NLO materials.

A pcu-type metal–organic framework with spindle [Zn7(OH)8]6+cluster as secondary building units

The in situ solvothermal reaction of 9,10-dicyanoanthracene and ZnCl(2)/NaN(3) gave the complex, {[Zn(7)(OH)(8)(DTA)(3)].H(2)O}(n) () (DTA(2-) = 9,10-ditetrazolateanthracene), which presents a pcu-type topological framework formed by DTA(2-) bridging unprecedented heptanuclear spindle [Zn(7)(OH)(8)](6+) clusters as SBUs, and exhibits strong luminescent emission with long lifetime.