Removal of Circulating Tumor Cells from Blood Samples of Cancer Patients Using Highly Magnetic Nanoparticles: A Translational Research Project

The count of circulating tumor cells (CTCs) has been associated with a worse prognosis in different types of cancer. Perioperatively, CTCs detach due to mechanical forces. Diagnostic tools exist to detect and isolate CTCs, but no therapeutic technique is currently available to remove CTCs in vivo from unprocessed blood. The aim of this study was to design and test new magnetic nanoparticles to purify whole blood from CTCs. Novel magnetic carbon-coated cobalt (C/Co) nanoparticles conjugated with anti-epithelial cell adhesion molecule (EpCAM) antibodies were synthesized, and their antifouling and separation properties were determined. The newly developed C/Co nanoparticles showed excellent separation and antifouling properties. They efficiently removed tumor cells that were added to healthy subjects’ blood samples, through an anti-EpCAM antibody interaction. The nanoparticles did not interact with other blood components, such as lymphocytes or the coagulation system. In blood samples of carcinoma patients suffering from metastatic disease, on average, ≥68% of CTCs were removed. These nanoparticles could prompt the development of a blood purification technology, such as a dialysis-like device, to perioperatively remove CTCs from the blood of cancer patients in vivo and potentially improve their prognosis.

Ni or FeO nanocrystal-integrated hollow (solid) N-doped carbon nanospheres: preparation, characterization and electrochemical properties

In this paper, phase-pure monodisperse NiO nanocrystals were prepared in a temperature-dependent manner via a thermal decomposition approach, showing sphere-like shapes and snowflake-like NiO arrays. Such hydrophobic NiO nanocrystals were converted into hydrophilic nickel oxide-sodium oleate-Pluronic P123 (NiO-SO-P123) micelles in aqueous solution. Phenolic resin (PR) formed in situ was successfully deposited on the hydrophilic area of the NiO-SO-P123 micelles via a heterogeneous nucleation mechanism to form NiO-phenolic resin nanospheres (NiO-PRNSs) with uniform particle size. By adjusting the size and amount of NiO nanocrystals used, the diameter of the obtained NiO-PRNSs can be effectively controlled from 185 to 103 nm, and a narrow size distribution is seen, revealing the effects of the NiO nanocrystals on the reconstructed NiO-integrated micellar size. Meanwhile, the morphology (ring buoy, semi-bowl, sphere) depends upon the initial amount of NiO. The carbonization of NiO-PRNSs produced Ni(0)-integrated hollow N-doped carbon nanospheres (Ni(0)-HNCNSs), which involved the conversion of NiO to Ni(0) and the contraction of particle size, and the size and distribution was affected by the starting amount of NiO. However, upon using monodisperse and polyhedral FeO nanocrystals, the obtained FeO-free/-incompletely-filled/-fully-filled core-shell structured Fe-PRNSs showed relatively uniform particle size, except for when multiple FeO cores formed large FeO-PR nanospheres after starting with the same initial FeO size. The carbonized FeO-HNCNSs still preserved a pomegranate-like core-shell structure with uniform size and there was no change in the size of the FeO nanocrystals. Moreover, high-loaded Ni(0)-integrated hollow or solid N-doped carbon microspheres or flakes can be synthesized via a one-pot method, but with a broad size range, showing highly uniform Ni distribution with a Ni size as small as 8.5 nm. Note that Ni(0)- and FeO-HNCNSs were prepared for the first time according to our knowledge. Finally, low-loaded Ni- and FeO-HNCNSs with uniform morphology and size were chosen as representatives to investigate their electrochemical properties for lithium-ion batteries (LIBs), showing excellent lithium storage properties and superior reversibility. This study provides a potential strategy for controlling the sizes and morphologies of metal-integrated carbon materials to obtain adjustable electrochemical properties.

Synthesis of surface functionalized hollow microporous organic capsules for doxorubicin delivery to cancer cells

Functionalized hypercrosslinked hollow microporous capsules are demonstrated to have potential applications in targeted delivery of anticancer drugs.

Shape Engineering of Biomass-Derived Nanoparticles from Hollow Spheres to Bowls through Solvent-Induced Buckling

The realization of asymmetric hollow carbonaceous nanostructures remains a great challenge, especially when biomass is chosen as the carbon resource through hydrothermal carbonization (HTC). Herein, a simple and straightforward solvent-induced buckling strategy is demonstrated for the synthesis of asymmetric spherical and bowl-like carbonaceous nanomaterials. The formation of the bowl-like morphology was attributed to the buckling of the spherical shells induced by the dissolution of the oligomers. The bowl-like particles prepared through this solvent-driven approach demonstrated a well-controlled morphology and a uniform particle size of approximately 360 nm. The obtained nanospheres and nanobowls were loaded with CoS₂ nanoparticles to act as heterogeneous catalysts for the selective hydrogenation of aromatic nitro compounds. As expected, the CoS₂ /nanobowls catalyst showed good tolerance to a wide scope of reducible groups and afforded both high activity and selectivity in almost all the tested substrates.

Water dispersible surface-functionalized platinum/carbon nanorattles for size-selective catalysis

Selective dealloying of metal nanoparticles results in rattle-type hollow carbon nanoshells enclosing platinum nanoparticles, which are able to perform size-selective catalysis. Selective functionalization of the outer graphene-like carbon surface prevents agglomeration and leads to well dispersible nanocatalysts in aqueous solutions. The synthesis starts with the production of nanoparticles with a cobalt-platinum-alloy core surrounded by graphene-like carbon via reducing flame spray synthesis. After surface functionalization, simultaneous pore formation in the shell-wall and dissolution of the cobalt results in platinum encapsulated in hollow carbon nanospheres. Catalytic oxidation of differently sized sugars (glucose and maltoheptaose) reveales size-selective catalytic properties of these platinum nanorattles.

Selective Low-Energy Carbon Dioxide Adsorption Using Monodisperse Nitrogen-Rich Hollow Carbon Submicron Spheres

Monodisperse, nitrogen-doped hollow carbon spheres of submicron size were synthesized using hexamethoxymethylmelamine as both a carbon and nitrogen source in a short (1 h) microwave-assisted synthesis. After carbonization at 550 °C, porous carbon spheres with a remarkably high nitrogen content of 37.1% were obtained, which consisting mainly of highly basic pyridinic moieties. The synthesized hollow spheres exhibited high selectivity for carbon dioxide (CO₂) over nitrogen and oxygen gases, with a capture capacity up to 1.56 mmol CO₂ g^-1. The low adsorption enthalpy of the synthesized hollow carbon spheres permits good adsorbent regeneration. Evaluation of the feasibility of scaling up shows their potential for large-scale applications.

Flower-Like Molybdenum Disulfide for Polarity-Triggered Accumulation/Release of Small Molecules

Flower-like molybdenum disulfide (MoS₂) with rich edge sites has been prepared by the hydrothermal method. The edge sites possess polarity due to the noncentrosymmetric Mo-S on exposed (100) facets and thus show a strong electrostatic attraction toward polar species. The flower-like MoS₂ can be used as small-molecule carriers for the model drug, Rhodamine B (RhB). The results prove that flower-like MoS₂ have fast adsorption kinetics and perform a switchable accumulation/release with response to the solvent polarity. An outstanding reusability can be found in flower-like MoS₂ due to little cargo retention, and the recycle of adsorption can be repeated 100 times with above 88.5% of the adsorption capacity retained. The flower-like MoS₂ with solvent polarity-triggered loading/release can be extended to controlled release and color switch of display.

N-Doped porous carbon nanotubes: synthesis and application in catalysis

Hierarchically porous nitrogen-doped carbon nanotubes were prepared; they exhibited high catalytic efficiency for C–H arylation, hydrogen transfer and oxidation reactions.