Multicomponent Reactions Among Alkyl Isocyanides, sp reactants, and sp2 Carbon Cages

We explored the reactivity and substrate scope of the reactions among an alkyl isocyanide, an sp-hybridized reactant (i.e. alkyne or allene), and a carbon cage, as a new approach to functionalize fullerenes and metallofullerenes. This account summarizes the key findings in our recent published work, and some original data for the reaction involving an isocyanide, allenes, and metallofullerene Lu3N@C80.

Regioselective CF2 functionalization of Sc3N@D3h(5)-C78

We report synthesis and computational study of Sc3N@C78(CF2) – an analog of the previously reported Sc3N@C80(CF2) with a less common carbon cage whose chemical properties presently remain far less studied....

ZIF-67-derived N-doped double layer carbon cage as efficient catalyst for oxygen reduction reaction

The slow kinetic of oxygen reduction reaction (ORR) hampers the practical application of energy conversion devices, such as fuel cells, metal-air batteries. Here, an efficient ORR electrocatalyst consists of Co, Ni co-decorated nitrogen-doped double shell hollow carbon cage (Ni-Co@NHC) was fabricated by pyrolyzing Ni-doped polydopamine wrapped ZIF-67. During the preparation, polydopamine served as a protective layer can effectively prevented the aggregation of Co and Ni nanoparticles during the pyrolysis process, and at the same time forming a carbon layer to grow a double layer carbon cage. This unique hollow structure endows the catalyst with a high specific surface area as well as more exposed active sites. Also benefited from the synergistic effect between Ni and Co nanoparticles, the Ni-Co@NHC catalyst lead to an outstanding ORR performance of half-wave potential (E1/2, 0.862 V), outperforms that of commercial Pt/C catalyst. Additionally, when Ni-Co@NHC was used in the cathode for the zinc-air battery, the cell exhibits high power density (108 mW cm-2) and high specific capacity (806 mAh g-1) at 20 mA cm-2 outperforming Pt/C. This work offers a promising design strategy for the development of high-performance ORR electrocatalysts.

An Update Report on the Biosafety and Potential Toxicity of Fullerene-Based Nanomaterials toward Aquatic Animals

Fullerene molecules are composed of carbon in the form of a hollow sphere, tube, or ellipsoid. Since their discovery in 1985, they have gained a lot of attention in many science fields. The unique carbon cage structure of fullerene provides immense scope for derivatization, rendering potential for various industrial applications. Thus, the prospective applications of fullerenes have led to assorted fullerene derivatives. In addition, their unique chemical structure also eases them to be synthesized through various kinds of conjugating techniques, where fullerene can be located either on the backbone or the branch chain. In this review, we have compiled the toxicity and biosafety aspects of fullerene in aquatic organisms since the frequent use of fullerene is likely to come in contact and interact with the aquatic environment and aquatic organisms. According to the current understanding, waterborne exposure to fullerene-based nanomaterials indeed triggers toxicities at cellular, organic, molecular, and neurobehavioral levels.

Toxicity and Antioxidant Activity of Fullerenol C60,70 with Low Number of Oxygen Substituents

Fullerene is a nanosized carbon structure with potential drug delivery applications. We studied the bioeffects of a water-soluble fullerene derivative, fullerenol, with 10-12 oxygen groups (F10-12); its structure was characterized by IR and XPS spectroscopy. A bioluminescent enzyme system was used to study toxic and antioxidant effects of F10-12 at the enzymatic level. Antioxidant characteristics of F10-12 were revealed in model solutions of organic and inorganic oxidizers. Low-concentration activation of bioluminescence was validated statistically in oxidizer solutions. Toxic and antioxidant characteristics of F10-12 were compared to those of homologous fullerenols with a higher number of oxygen groups:F24-28 and F40-42. No simple dependency was found between the toxic/antioxidant characteristics and the number of oxygen groups on the fullerene’s carbon cage. Lower toxicity and higher antioxidant activity of F24-28 were identified and presumptively attributed to its higher solubility. An active role of reactive oxygen species (ROS) in the bioeffects of F10-12 was demonstrated. Correlations between toxic/antioxidant characteristics of F10-12 and ROS content were evaluated. Toxic and antioxidant effects were related to the decrease in ROS content in the enzyme solutions. Our results reveal a complexity of ROS effects in the enzymatic assay system.

Aqueous C60 Fullerene Solution Effects on Cell Viability

Fullerenes are carbon nanoparticles with the ability to quench reactive oxygen species. The biomedical potential of fullerenes is diminished by their low solubility in water, but many approaches have been developed to bypass this problem, like chemical modification of the carbon cage and the use of the solvent exchange method to transfer fullerenes from one solvent to the other. These two approaches were used in this study. Carboxylated fullerene aqueous solution was acquired using solvent exchange method transferring fullerene nanoparticles (C60) from toluene to water. Effects of varying concentration (0.5, 1, 1.5, 2, 2.5, 3, 5, 10 µM) of aqueous fullerene solution on cell viability and their antioxidative capabilities were evaluated on PC-3 and on monocytes isolated from a blood donor using Resazurin Cell Viability Assay. PC-3 cell viability was drastically affected by the 10 µM fullerene solution but remained relatively stable when treated with other concentrations even after longer periods of incubation with resazurin dye. Elevated cell viability was observed in monocytes treated with various fullerene concentrations, possibly indicative of fullerene protective activity against oxidative stress.