Covalent Organic Framework Embedded with Magnetic Nanoparticles for MRI and Chemo-Thermotherapy

Abstract

Nanoscale imine-linked covalent organic frameworks (nCOFs) were first loaded with the anticancer drug Doxorubicin (Dox), coated with magnetic iron oxide nanoparticles (γ-Fe2O3 NPs), and stabilized with a shell of poly­(l-lysine) cationic polymer (PLL) for simultaneous synergistic thermo-chemotherapy treatment and MRI imaging. The pH responsivity of the resulting nanoagents (γ-SD/PLL) allowed the release of the drug selectively within the acidic microenvironment of late endosomes and lysosomes of cancer cells (pH 5.4) and not in physiological conditions (pH 7.4). γ-SD/PLL could efficiently generate high heat (48 °C) upon exposure to an alternating magnetic field due to the nCOF porous structure that facilitates the heat conduction, making γ-SD/PLL excellent heat mediators in an aqueous solution. The drug-loaded magnetic nCOF composites were cytotoxic due to the synergistic toxicity of Dox and the effects of hyperthermia in vitro on glioblastoma U251-MG cells and in vivo on zebrafish embryos, but they were not significantly toxic to noncancerous cells (HEK293). To the best of our knowledge, this is the first report of multimodal MRI probe and chemo-thermotherapeutic magnetic nCOF composites.

In vivo oral insulin delivery via covalent organic frameworks

“…S24d † ) indicates the presence of three distinct peaks at (i) 399.0 eV corresponding to the imine nitrogen, (ii) 399.9 eV associated with pyridinic nitrogen, and (iii) 400.7 eV attributed to quaternary nitrogen. 53 On the other hand, the N 1s spectrum for TTA-DFP-nCOF/insulin exhibits the contribution of nitrogen from amino and amide groups present in insulin (Fig. S26d † ).…”

“…S14 †). 53,54 The chemical stability of the TTA-DFP-nCOF under conditions designed to simulate the stomach environment (pH 2.0) as well as the bloodstream (pH 7.4) was assessed. The TTA-DFP-nCOF remained unaffected under both conditions as conrmed through TEM imaging (Fig.…”

Three‐Dimensional Covalent‐Organic Frameworks Loaded with Highly Dispersed Ultrafine Palladium Nanoparticles as Efficient Heterogeneous Catalyst

“…They hold advantages of great internal surface areas, low densities, and high thermal stabilities [6–9] . During the last decade, the researchers have witnessed tremendous potential applications of COFs, typically in gas storage and separation, semiconducting device, sensor, energy storage, and drug delivery [10–17] . Besides these applications, due to their modifiable internal surface and highly ordered porous structures, the application as topological heterogeneous catalyst has emerged recently [18–20] .…”

Recent advances of high performance magnetic iron oxide nanoparticles: Controlled synthesis, properties tuning and cancer theranostics

“…Trabolsi et al. [ 169 ] developed an anticancer drug DOX loaded covalent organic frameworks (nCOFs) composite which coated with γ‐Fe 2 O 3 NPs and stabilized with poly( l ‐lysine) cationic polymer for the first time. Unlike other drug carriers, the as‐prepared composite acts as the pH‐responsive agent to guarantee DOX selectively releasing at late endosomes and lysosomes of cancer cells within acidic microenvironment (pH 5.4) only, rather than pH 7.4 (physiological conditions).…”