A Bio-Conjugated Chlorin-Based Metal-Organic Framework for Targeted Photodynamic Therapy of Triple Negative Breast and Pancreatic Cancers.

The field of photodynamic therapy (PDT) has continued to show promise as a potential method for treating tumors. In this work a photosensitizer (PS) has been delivered to cancer cell lines for PDT by incorporation into the metal-organic framework (MOF) as an organic linker. By functionalizing the surface of MOF nanoparticles with maltotriose the PS can efficiently target cancer cells with preferential uptake into pancreatic and breast cancer cell lines. Effective targeting overcomes some current problems with PDT including long-term photosensitivity and tumor specificity. Developing a PS with optimal absorption and stability is one of the foremost challenges in PDT and the synthesis of a chlorin which is activated by long-wavelength light and is resistant to photo-bleaching is described. This chlorin-based MOF shows anti-cancer ability several times higher than that of porphyrin-based MOFs with little toxicity to normal cell lines and no dark toxicity.

Maltotriose Conjugated Metal-Organic Frameworks for Selective Targeting and Photodynamic Therapy of Triple Negative Breast Cancer Cells and Tumor Associated Macrophages.

Herein, we report a nano-MOF conjugated to maltotriose as a new DDS. MA-PCN-224-0.1Mn/0.9Zn showed its ability to target cancer and TAM. This novel MOF is an effective PDT agent and shows little dark toxicity, MA-PCN-224-0.1Mn/0.9Zn uptakes selectively into cancer cells. A well-suited size control methodology was used so that the nano-scaled MOFs may take advantage of the EPR effect. This development of a nano-scale MOF for PDT that is conjugated to a cancer targeting ligand represents a meaningful development for the use of MOFs as drug delivery systems.

Sulfur-Decorated Hyper-Cross-Linked Coal Tar: A Microporous Organic Polymer for Efficient and Expeditious Mercury Removal.

Hyper-cross-linked microporous organic polymers are a class of porous materials that have captured widespread attention owing to their high surface areas and wide range of monomeric sources. Balancing economy with performance is the initial hurdle when designing effective hyper-cross-linked microporous organic polymers. Herein, we demonstrated an inexpensive sulfurated solvent-knitted hyper-cross-linked microporous polymer scaffold, named sulfur-decorated hyper-cross-linked coal tar (CTHP-SES), utilizing coal tar as an aromatic monomer with numerous positions for potential chelation of toxic metals, particularly mercury, from water. The resulting material illustrated selective adsorption of mercury from both water (1037 mg g-1) and the gas phase (416 mg g-1) with rapid kinetics (183.67 mg min-1 g-1), good recyclability (4 runs), and excellent stability under both strong basic and acidic conditions. CTHP-SES was able to reduce the concentration of the Hg(II) solution from 1 mg L-1 to 32 µg L-1 after 10 min due in part to the promising distribution coefficient (Kd = 2.371 × 106 mL g-1). These results show that CTHP-SES offers a promising and practical platform to cope with a variety of environmental contaminations.

Applications of Dynamic Covalent Chemistry Concept towards Tailored Covalent Organic Framework Nanomaterials: A Review.

Covalent organic frameworks (COFs) are a rapidly developing class of materials that has been of immense research interest during the last ten years. Numerous reviews have been devoted to summarizing the synthesis and applications of COFs. However, the underlying dynamic covalent chemistry (DCC), which is the foundation of COFs synthesis, has never been systematically reviewed in this context. Dynamic covalent chemistry is the practice of using thermodynamic equilibriums to molecular assemblies. This Critical Review will cover the state-of-the-art use of DCC to both synthesize COFs and expand the applications of COFs. Five synthetic strategies for COF synthesis are rationalized, namely: modulation, mixed linker/linkage, sub-stoichiometric reaction, framework isomerism, and linker exchange, which highlight the dynamic covalent chemistry to regulate the growth and to modify the properties of COFs. Furthermore, the challenges in these approaches and potential future perspectives in the field of COF chemistry are also provided.

Green and Facile Synthesis of Highly Photoluminescent Multicolor Carbon Nanocrystals for Cancer Therapy and Imaging.

Carbon dots (CDs), as a new generation of fluorescent nanoparticles, have been greatly considered for different biomedical applications. In the present study, a one-pot hydrothermal method was developed for the synthesis of a series of carbon dots (CDs) for cancer imaging and therapy. Taxane diterpenoids were utilized as the carbon source, different diamines were used as the nitrogen source, and folic acid was used as a targeting agent. High-quality photostable and multicolor (blue and green) carbon nanocrystals with a hexagonal shape, a narrow size distribution of less than 20 nm, and high fluorescence quantum yield of up to 50.4% were obtained from taxanes in combination with m-phenylenediamine and folic acid to give the best results. The nanoparticles displayed a potent anticancer activity with IC50 values of 31.3 ± 2.7 and 34.1 ± 1.1 µg mL-1 for the human MCF-7 and HeLa cancer cell lines, respectively, and IC50 value of 120.5 ± 3.8 µg mL-1 on the normal human fibroblast cells. The flow cytometry studies determined apoptosis-mediated cell death as the main anticancer mechanism of CDs, and the molecular studies revealed the induction of both extrinsic and intrinsic apoptosis pathways. The overall results indicated the great potential of synthesized CDs for the simultaneous cancer imaging and therapy.