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Guest-host Raman under liquid nitrogen spectroscopy (GHRUNS) is introduced whereby solid-state guest molecules are isolated inside cage-like host environments for the facile acquisition of their Raman spectra. This convenient method features reduced fluorescence, the analysis of populations in their ground states, and increased signal to noise ratios. Samples are also preserved through the reduction of thermal degradation and oxidation. To demonstrate the benefits of this new method, Raman spectra of the ubiquitous molecule C 60 inside a cage of water ice are presented. Using this technique, a new normal mode of C 60 is elucidated. The GHRUNS methodology is of interest to those seeking to acquire and characterize the vibrational spectra, structure, and properties of emissive, air-sensitive molecules., (© 2022 Wiley-VCH GmbH.)

Chiral induction is an emerging topic of interest in various areas of chemistry because of its relationship to the elusive mechanism of spontaneous symmetry breaking in nature. Buckminsterfullerene (C 60 ) with the shape of a highly symmetric truncated icosahedron has rarely been referred for chiral induction due to the difficult symmetry breaking. In this work, we demonstrate that a chiral metal-organic framework (MOF) can provide a key field for chiral induction. C 60 could be incorporated into the chiral nanochannels of the MOF using an in situ self-assembly strategy. The circular dichroism spectra of the resulting nanocomposites showed an intense chiral signal in the absorption region of C 60 . Experimental and theoretical studies showed that this unprecedented chiral induction of C 60 was attributed to hybridization of the molecular orbitals through a close association with the pore surface of the MOF. Our method can endow highly symmetric achiral compounds with chirality, paving the new way toward fabrication of novel chiral nanomaterials., (© 2021 Wiley-VCH GmbH.)

The buckminsterfullerene (C60) is considered as a relevant candidate for drug and gene delivery to the brain, once it has the ability to cross the blood-brain barrier. However, the biological implications of this nanomaterial are not fully understood, and its safety for intracerebral delivery is still debatable. In this study, we investigated if C60 particle size could alter its biological effects. For this, two aqueous C60 suspensions were used with maximum particle size up to 200nm and 450nm. The suspensions were injected in the hippocampus, the main brain structure involved in memory processing and spatial localization. In order to assess spatial learning, male Wistar rats were tested in Morris water maze, and the hippocampal BDNF protein levels and gene expression were analyzed. Animals treated with C60 up to 450nm demonstrated impaired spatial memory with a significant decrease in BDNF protein levels and gene expression. However, an enhanced antioxidant capacity was observed in both C60 treatments. A decrease in reactive oxygen species levels was observed in the treatments with suspensions containing particles measuring with up to 450nm. Thiobarbituric acid reactive substances, glutamate cysteine ligase, and glutathione levels showed no alterations among the different treatments. In conclusion, different particle sizes of the same nanomaterial can lead to different behavioral outcomes and biochemical parameters in brain tissue., (Copyright © 2017 Elsevier Inc. All rights reserved.)

C60 fullerene (C60), or buckminsterfullerene, is a spherical arrangement of 60 carbon atoms, having a diameter of approximately 1 nm, and is produced naturally as a by-product of combustion. Due to its small size, C60 has attracted much attention for use in a variety of applications; however, insufficient information is available regarding its toxicological effects. The effects on respiratory toxicity and immunotoxicity of C60 aggregates (50 nm [nano-C60] and 1 μm [micro-C60] diameter) were examined in B6C3F1/N mice and Wistar Han rats after nose-only inhalation for 13 weeks. Exposure concentrations were selected to allow for data evaluations using both mass-based and particle surface area-based exposure metrics. Nano-C60 exposure levels selected were 0.5 and 2 mg/m 3 (0.033 and 0.112 m 2 /m 3 ), while micro-C60 exposures were 2, 15 and 30 mg/m 3 (0.011, 0.084 and 0.167 m 2 /m 3 ). There were no systemic effects on innate, cell-mediated, or humoral immune function. Pulmonary inflammatory responses (histiocytic infiltration, macrophage pigmentation, chronic inflammation) were concentration-dependent and corresponded to increases in monocyte chemoattractant protein (MCP)-1 (rats) and macrophage inflammatory protein (MIP)-1α (mice) in bronchoalveolar lavage (BAL) fluid. Lung overload may have contributed to the pulmonary inflammatory responses observed following nano-C60 exposure at 2 mg/m 3 and micro-C60 exposure at 30 mg/m 3 . Phenotype shifts in cells recovered from the BAL were also observed in all C60-exposed rats, regardless of the level of exposure. Overall, more severe pulmonary effects were observed for nano-C60 than for micro-C60 for mass-based exposure comparisons. However, for surface-area-based exposures, more severe pulmonary effects were observed for micro-C60 than for nano-C60, highlighting the importance of dosimetry when evaluating toxicity between nano- and microparticles., Competing Interests: Declaration of Interest This work was supported [in part] by the Intramural Research Program of the National Institutes of Health (NIH), National Institute of Environmental Health Sciences (NIEHS) and by NTP Contracts N01-ES-55538 and N01-ES-5553.

In this manuscript, we describe the single-step preparation of a cyclic tetramer of acenaphthylene through a Lewis acid-catalyzed aldol cyclization of 1-acenaphthenone. The previously unexplored cyclic tetramer material differs from the better-known cyclic trimer, decacyclene, due to the presence of a central eight-membered ring. This ring not only forces the molecule to distort significantly from planarity, but is also responsible for its unique electronic properties, including a decrease in the reduction potential (by about 0.4 eV) and optical gap (by about 0.73 eV), compared to the more planar decacyclene. The synthesized compound crystallizes into a unique packing structure with significant π-stacking observed between adjacent molecules. Furthermore, due to its saddle-like shape, the cyclic tetramer is able to form shape-complementary interactions between its concave surface and the convex outer surface of buckminsterfullerene to generate cocrystalline supramolecular assemblies., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This paper inquires the C60 capabilities to contain radio-iodide ((131)I2) molecules. The encapsulation conditions are investigated applying first principles method to simulate with geometric optimizations and molecular dynamics at 310 K and atmospheric pressure. We find that the n(131)I2@C60 system, where n = 1, 2, 3…, is stable if the content does not exceed three molecules of radio-iodide. The application of density functional theory allows us to determine that, the nanocapsules content limit is related with the amount of charge that is transferred from the iodine (131)I2 molecules to the carbon atoms in the fullerene surface. The Mulliken population analysis reveals that the excess of charge increases the repulsive forces between atoms and the bond length average in the C60 structure. The weakened bonds easily break and will critically damage the encapsulation properties. Additionally, we test the interaction nanocapsules with different amounts of radioactive iodine diatomic molecules content with calcium atoms, and find that only the fullerene containing one radioactive iodine diatomic molecule was able to interact with up to nine atoms of calcium without disrupting or cracking. Other fullerenes with two and three radio iodine diatomic molecules cannot resist the interaction with a single calcium atom without cracking or being broken.

Docetaxel has always attracted the researchers owing to its promises and challenges. Despite marked efficacy, concerns like poor aqueous solubility, lower bioavailability, poor tissue penetration and dose related side-effects offer further scope of research on docetaxel. The present study aims to explore the potential of C60-fullerenes in the delivery of docetaxel to cancerous cells. C60-fullerenes were carboxylated, acylated and conjugated with the drug. The chemical processes were monitored by UV, FT-IR and NMR spectroscopy. The conjugate was further characterized for drug loading, micromeritics, drug release, morphology and evaluated for in-vitro cytotoxicity, haemolysis and in-vivo pharmacokinetic profile. The developed nanoconstruct was able to enhance the bioavailability of docetaxel by 4.2 times and decrease the drug clearance by 50%. The developed system was able to control the drug release and was found to be compatible with erythrocytes. The cytotoxic potential on studied MCF-7 and MDA-MB231 cell lines was also enhanced by many folds, indicating marked promise in efficacy enhancement and dose reduction. The present findings are encouraging and offer a technique to enhance the delivery and efficacy potential of anticancer agents, especially belonging to BCS class IV., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The enhanced production and environmental release of Buckminsterfullerene (C60) nanoparticles will likely increase the exposure and risk to soil dwelling organisms. We used (1)H NMR-based metabolomics to investigate the response of Eisenia fetida earthworms to sub-lethal C60 nanoparticle exposure in both contact and soil tests. Principal component analysis of (1)H NMR data showed clear separation between controls and exposed earthworms after just 2 days of exposure, however as exposure time increased the separation decreased in soil but increased in contact tests suggesting potential adaptation during soil exposure. The amino acids leucine, valine, isoleucine and phenylalanine, the nucleoside inosine, and the sugars glucose and maltose emerged as potential bioindicators of exposure to C60 nanoparticles. The significant responses observed in earthworms using NMR-based metabolomics after exposure to very low concentrations of C60 nanoparticles suggests the need for further investigations to better understand and predict their sub-lethal toxicity., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The solvent-mediated interaction of C60 fullerenes in liquid water is examined by using the combination of the probabilistic hydrogen bond model with the density functional theory. This combination allows one to take into account the effect of hydrogen bonding between water molecules on their interaction with fullerenes and to construct an approximation for the distribution of water molecules in the system, which provides an efficient foundation for studying hydrophobic phenomena. Our numerical evaluations predict the solvent-induced interaction of two C60 fullerenes in water at 293 K to have an oscillatory-repulsive character (previously observed in molecular dynamics simulations) only when the vicinal water-water hydrogen bonds are slightly weaker than bulk ones. Besides indicating the direction of the energetic alteration of water-water hydrogen bonds near C60 fullerenes, our model also suggests that the hydrogen bonding ability of water plays a defining role in the solvent-mediated C60-C60 repulsion.

The three known classes of convex polyhedron with equal edge lengths and polyhedral symmetry--tetrahedral, octahedral, and icosahedral--are the 5 Platonic polyhedra, the 13 Archimedean polyhedra--including the truncated icosahedron or soccer ball--and the 2 rhombic polyhedra reported by Johannes Kepler in 1611. (Some carbon fullerenes, inorganic cages, icosahedral viruses, geodesic structures, and protein complexes resemble these fundamental shapes.) Here we add a fourth class, "Goldberg polyhedra," which are also convex and equilateral. We begin by decorating each of the triangular facets of a tetrahedron, an octahedron, or an icosahedron with the T vertices and connecting edges of a "Goldberg triangle." We obtain the unique set of internal angles in each planar face of each polyhedron by solving a system of n equations and n variables, where the equations set the dihedral angle discrepancy about different types of edge to zero, and the variables are a subset of the internal angles in 6gons. Like the faces in Kepler's rhombic polyhedra, the 6gon faces in Goldberg polyhedra are equilateral and planar but not equiangular. We show that there is just a single tetrahedral Goldberg polyhedron, a single octahedral one, and a systematic, countable infinity of icosahedral ones, one for each Goldberg triangle. Unlike carbon fullerenes and faceted viruses, the icosahedral Goldberg polyhedra are nearly spherical. The reasoning and techniques presented here will enable discovery of still more classes of convex equilateral polyhedra with polyhedral symmetry.

The important photoluminescence enhancement found in Carbon Dots (CDs) obtained from carbonaceous nanomaterials when passivating with acetone is shown in this paper, in which this type of passivation has not been reported previously. Analytical fluorescent assays were performed with the selected CDs using two different pollutants as target analytes. The results show that the optimal conditions for detecting 2,4-dinitrophenol (DNP) were at pH 3.5 while in case of 2-amino-3,4,8-trimethyl-3H-imidazo[4,5-f]quinoxaline (4,8-DiMeIQx) were found at physiological pH. The fascinating ability of CDs to interact with certain molecules under certain conditions gave rise to explore some useful applications for a quick detection of contaminants by simply monitoring the photoluminescence of CDs as shown in this article., (Copyright © 2013 Elsevier B.V. All rights reserved.)