Fullerene Complexes Research Articles

Combined Action of Hyper-Harmonized Hydroxylated Fullerene Water Complex and Hyperpolarized Light Leads to Melanoma Cell Reprogramming In Vitro.

(1) Background: Their unique structure and electron deficiency have brought fullerenes into the focus of research in many fields, including medicine. The hyper-harmonized hydroxylated fullerene water complex (3HFWC) formulation has solved the limitations of the poor solubility and bioavailability of fullerenes. To achieve better antitumor activity, 3HFWC was combined with short-term irradiation of cells with hyperpolarized light (HPL) generated by the application of a nanophotonic fullerene filter in a Bioptron® device. The benefits of HPL were confirmed in the microcirculation, wound healing and immunological function. (2) Methods: B16, B16-F10 and A375 melanoma cells were exposed to a wide spectrum of 3HFWC doses and to a single short-term HPL irradiation. (3) Results: Apart from the differences in the redox status and level of invasiveness, the effects of the treatments were quite similar. Decreased viability, morphological alteration, signs of melanocytic differentiation and cellular senescence were observed upon the successful internalization of the nanoquantum substance. (4) Conclusions: Overall, 3HFWC/HPL promoted melanoma cell reprogramming toward a normal phenotype.

Diversity of Metal-Fullerene Framework Structures Regulated by Metal Salts.

Taking into account the diversity of fullerene ligands and metal salts, metal–fullerene frameworks (MFFs) present a variety of structures. Currently, the structural control of MFFs mainly relies on the design and synthesis of fullerene ligands, while the influence of metal building units on the structures has been rarely studied. The present work represents a systematical investigation of fullerene-linked supramolecular architectures incorporating different metal salts. Treatment of a bidentate N,N-donors fullerene ligand (L1) with six metal salts ([Zn(NO3)2·6H2O, Cd(NO3)2·4H2O, Cu(NO3)2·3H2O, Cu(OAc)2·H2O, FeCl2·4H2O and FeCl3·6H2O]) produced six one-dimensional MFFs, i.e., ZnL1(NO3)2(H2O)2 (1), CdL1(NO3)2 (2), Cu(L1)(H2O)2(NO3)2 (3), CuL1(OAc)(CH3O) (4), FeL1Cl2 (5) and FeL1Cl2(FeCl4) (6). Compounds 1–3, built with nitrates with different metal centers (M(NO3)2, M = Zn, Cd, Cu), present a 1D stair-like, 1D zigzag, and 1D linear chain structure, respectively. Compound 4, synthesized with another Cu(II) salt, Cu(OAc)2, displays a dinuclear Cu-Cu connected 1D stair-like chain structure, rather than the single Cu linked 1D linear chain obtained from Cu(NO3)2. Compounds 5 and 6, assembled from iron chloride of different oxidation states (Fe(II)Cl2 and Fe(III)Cl3) reveal a 1D zigzag and a 1D stair-like chain structure, respectively. The results demonstrate the significant influences of metal salts on the structures of metal–fullerene frameworks.

A novel supramolecular porphyrin-fullerene compound: Crystal structure and photophysical properties

A novel porphyrin-(60)fullerene complex [bis(5,10,15,20-tetra-3-pyridinyl-21H, 23H-porphine)](60)-fullerene tetrahydrate, C60(Por)2·4H2O (1; Por ​= ​5,10,15,20-tetra-3-pyridinyl-21H,23H-porphine) was synthesized via a hydrothermal reaction of 5,10,15,20-tetra-3-pyridinyl-21H,23H-porphine, C60, xylene and distilled water. The crystal structure is characterized by single-crystal X-ray diffraction. Compound 1 is characteristic of an isolated structure and each molecule contains two 5,10,15,20-tetra-3-pyridinyl-21H,23H-porphine moieties surrounding one C60 moiety, accompanied by four lattice water molecules. The porphine molecule features a saddle-distorted nonplanar macrocycle. The molecules in 1 are interconnected through van der Waals interactions to yield a supramolecular network. The photophysical properties of 1 in ethanol solution have been studied by photoluminescence and UV–Vis–NIR absorbance. A solution photoluminescence measurement shows that compound 1 can emit red photoluminescence with the maximum peak locating at 656 ​nm. Compound 1 has CIE (Commission Internationale de I'Éclairage) chromaticity coordinates of 0.70 and 0.30. The lifetime is 1.501 us and the quantum yield of 1 is 0.9%.

A gold nanoparticles and hydroxylated fullerene water complex as a new product for cosmetics

Three types of gold nanoparticles (AuNPs) were synthesised with a custom-made Ultrasonic Spray Pyrolysis (USP) device, from aqueous solutions of gold (III) chloride (AuCl3) and gold (III) acetate (AuC6H12O6), with an initial concentration of Au 0.5 g/L. AuNPs were collected in suspensions of deionised (D.I.) water with the stabilisers polyvinylpyrrolidone (PVP) or polyethylene glycol (PEG), followed by the process of freeze drying the AuNPs to be useful as a new additive for the cream. The standard cream base was used as a matrix for preparation of three types of cream with AuNPs in the same concentration ratios. The third AuNPs cream was prepared with a patented hydroxylated fullerene water complex (3HFWC-W) matrix. To examine the effect of AuNPs as additive in creams, a six-week study of test creams was conducted on 33 volunteers with no dermatological diseases. During the study three main parameters of the skin where measured: Collagen quality, skin moisturisation and the epidermis-dermis function. The results of the study found improvements of collagen quality between 18-24 %, achieved due to the use of AuNPs in standard creams, while the cream with the combination of 3HFWC-W and AuNPs gave significantly higher improvements with a value of 45.7 %. It was also discovered that hydration of the skin (stratum cornum) increased by 6.4-9.6 % in standard creams with AuNPs, and 73.7 % in the 3HFWC/AuNPs` cream. Similar results were measured by the epidermis-dermis function, where 24-28 % improvement for standard creams with AuNPs was identified, and 38.4 % for the cream 3HFWC-W/AuNPs.

Novel Lanthanide(III) Complexes with Pyrrolidinofullerene Ligands: Synthesis and Characterization

Novel europium and samarium complexes with pyrrolidinofullerene-based ligands are synthesized. Their compositions and molecular structures are elucidated using elemental analysis, MALDI-TOF mass spectrometry, as well as FTIR and NMR spectroscopy. It is shown that the metal ion coordinates with one pyrrolidinofullerene molecule. The photoluminescence spectra of the resulting complexes are similar to those of the free fullerene ligand.

Amphiphilic γ-cyclodextrin–fullerene complexes with photodynamic activity

High-speed vibration milling of a mixture of lipophilic γ-cyclodextrin (γ-CD), hydrophilic γ-CD and fullerene or functionalization of preformed γ-CD–fullerene complexes afforded amphiphilic γ-CD–fullerene complexes with high photodynamic activity.

AMPEROMETRIC IMMUNOSENSORS BASED ON CARBON NANOMATERIALS AND RHENIUM CLUSTERS FOR THE DETERMINATION OF TRICYCLIC ANTIDEPRESSANTS IN A SEQUENTIAL INJECTION SYSTEM

A method of sequential injection determination of tricyclic antidepressants (amitriptyline, desipramine, imipramine) using amperometric immunosensors based on screen-printed graphite electrodes modified by carbon nanomaterials (carbon nanotubes, graphene oxide or fullerene) in combination with hexarhenium chalcogenide clusters is proposed. Sequential injection analysis was performed at a sweep rate of 10 mV/s; the flow rate (supporting electrolyte – phosphate buffer solution with pH 7.0) was also varied from 20 to 40 µl/s. Composition of the modifier affects the analytical capability of immunosensors. Screening of various types of modifiers showed that the immunosensor based on graphene oxide and cyanide complexes of rhenium chalcogenide clusters exhibited the highest sensitivity of 23.9±0.9 with a range of working concentrations of 1·10–10–1·10–5 M, and even wider range of detectable concentrations, 1·10–10–1·10–4 M was observed for the immunosensor based on fullerene and cyanide complexes of rhenium chalcogenide clusters. The lowest limit of the determined contents was (4–7)·10–11 M. Relative standard deviation of repeatability (Sr) did not exceed 0.046. The results obtained show that the proposed immunosensors can be used in sequential injection determination of trace amounts of medicinal compounds (antidepressants) in biomedical objects.

Nitrogen-doped molecular bowls as electron donors in photoinduced electron transfer reactions.

In recent years, the chemistry of curved π-conjugated molecules has experienced a sharp rise. The inclusion of a heteroatom in the carbon network significantly affects its semiconducting properties. In this work, we computationally study the photoinduced electron transfer in a series of C60 fullerene complexes with experimentally established nitrogen-doped molecular bowls. Our results demonstrate that introducing nitrogen into pentagonal rings of the bowl-shaped π-conjugated molecules and extending the π-conjugation can modulate their electron-transfer properties. Among the studied complexes, the hub-NCor⊃C60 complex exhibits the most desirable combination of ultrafast charge separation and slow charge recombination, suggesting its potential use in photovoltaics.

Fullerene-Filtered Light Spectrum and Fullerenes Modulate Emotional and Pain Processing in Mice

The most symmetric molecule, Buckminster fullerene C60, due to its unique properties, has been intensively studied for various medical and technological advances. Minimally invasive and minimally toxic treatments hold great promise for future applications. With this in mind, this research exploited the physical properties of fullerene molecules for potential therapeutic effects. Pristine fullerenes have peak absorbance in the 380–500 nm range, making them an attractive violet-blue light filter. Since spectral quality of light can affect behavior, this research used resting state functional magnetic resonance imaging (rs fMRI) and behavioral testing to directly evaluate the effects of fullerene-filtered light on brain processing and behavior in mice. The same method was used to study if hydroxyl fullerene water complexes (3HFWC), with or without fullerene-filtered light, modulated brain processing. A month-long, daily exposure to fullerene-filtered light led to decreased activation of the brain area involved in emotional processing (amygdala). Water supplemented with 3HFWC resulted in an activation of brain areas involved in pain modulation and processing (periaqueductal gray), and decreased latency to first reaction when tested with a hot plate. The combination of fullerene-filtered light with 3HFWC in drinking water led to restored sensitivity to a hot plate and activation of brain areas involved in cognitive functions (prelimbic, anterior cingulate and retrosplenial cortex). These results uncovered the potential of fullerene-filtered light to impact emotional processing and modulate pain perception, indicating its further use in stress and pain management.

Remarkable nonlinear optical response of Mn@C20 (M = Na & K and n = 1–6); a DFT outcome

Electronic, optical and nonlinear (NLO) optical properties of Na and K (single and multiple) doped C20 fullerene are investigated via density functional theory (DFT) methods. It is observed that the exohedral interaction of single and multi-doped (Na & K) with the C20 surface is highly exothermic, whereas endohedral interaction is highly endothermic (energetically non-favorable). Among all single and multi-doped complexes of C20, K6@C20 shows the highest thermodynamic stability having interaction energy of −131.76 kcal mol-1. The HOMO-LUMO energy gaps are effectively reduced, and this reduction is more prominent in multi-doped complexes compared to single atom doped complexes. TDOS plots of all doped complexes confirmed the involvement of metal atoms with C20 in newly generated HOMO orbitals. First hyperpolarizability analysis revealed the NLO response of newly designed single and multi-doped complexes. It is observed that the doping of multiple atoms of metals (Na & K) significantly increased the first hyperpolarizability (βo), directly related with the NLO response. Among all considered Na and K complexes of C20 fullerene, K5@C20 has the highest hyperpolarizability value i.e. 1.88×105 a.u.

Metal doped fullerene complexes as promising drug delivery materials against COVID-19

An outbreak of respiratory disorder caused by coronavirus has been named as coronavirus infection 2019 (COVID-19). To find a specific treatment against this disease researchers are at the frontline. To cure COVID-19, favipiravir (FPV) has been reported as an effective drug based on its high recovery rate. Among nanomaterials, fullerene C60 has achieved enormous attention as a drug delivery vehicle due to its good bioavailability and low toxicity. Hence, in this work, we have investigated the potential of metal-doped fullerene as a drug carrier, based on DFT calculations by using M06-2X functional and 6-31G(d) basis set in water media. In this research electronic parameters and adsorption energy of FPV on interaction with metal-doped (Cr, Fe, and Ni) fullerene is studied. The charge transfer between drug and doped fullerene has been studied through electrophilicity indexes. The structural and electronic properties are explored in terms of adsorption energy through frontier molecular orbital (FMO) and density of state (DOS). It is observed that doping of fullerene C60 with Cr, Fe, and Ni metals significantly enhances the drug delivery rate and provides numerous advantages including controlled drug release at specific target sites which minimize the generic collection in vivo and reduce the side effects. Thusly, it is suggested that our designed metal-doped complexes might be efficient candidates as drug delivery materials for COVID-19 infection.Graphic abstract Supplementary InformationThe online version contains supplementary material available at 10.1007/s11696-021-01815-4.

How Can the η1-Type Fullerene-Metal Bond Survive? A Systematic Survey of Reactions between Mono-EMFs and (M′Ln)2 Dimers

Recently, one η1-coordinated complex of endohedral metallofullerene (EMF) Y@C2v(9)-C82[Re(CO)5] has been synthesized and characterized with a highly efficient radical-coupling methodology by performing a photochemical reaction between Y@C2v(9)-C82 and [Re(CO)5]2 complexes. Theoretical investigations with the density functional theory reveal that this complex is stabilized by an ionic C-Re bond. The reactions of M@C2v(9)-C82 (M = Sc, Y, La) with [Re(CO)5]2 suggest that the reaction energies differ little because of similar single occupied molecular orbitals (SOMOs) of M@C2v(9)-C82. In the reactions of Y@C2v(9)-C82 with various transition-metal complexes [M'Ln]2 (M' = Mn, Tc, Re, Fe, Ru, Os, Co, Rh, Ir), the C-M' bonds with Mn, Tc, Re, Fe, Ru, and Os can stably exist, whereas those with Co, Rh, and Ir are unstable. Further analyses disclose that, in each element group, the stability of the C-M' bond is mainly determined by the bond energy of the M'-M' bond, which is related to the dσ orbital of the M'Ln species. Moreover, the very-low-energy dσ orbitals and large geometrical distortions of M'(CO)4 (M' = Co, Rh, Ir) lead to poor stabilities of the C-M' (M' = Co, Rh, Ir) bonds. As comparison, the reactions of Y@Cs(6)-C82 and La@C72 have been investigated. The Y@Cs(6)-C82 structure is more reactive toward the [M'Ln]2 complexes than Y@C2v(9)-C82 thanks to a lower SOMO of Y@Cs(6)-C82 than that of Y@C2v(9)-C82, which derives from position change of the Y atom in Cs(6)-C82 during the reactions. However, the formation of [Y@Cs(6)-C82]2 suppresses the formation of several C-M' bonds. The reactivity of La@C72 is weak due to a high LUMO+1 of C72, which leads to a high SOMO of La@C72. We believe that this theoretical study provides primary principles of radical-coupling reactions of EMFs and will be valuable for future research of organometallic complexes of fullerene.

Pressure-Induced Donor–Acceptor Charge Transfer in a Fullerene Molecular Complex with Ferrocene

The pressure-induced charge transfer in a molecular complex of fullerene with ferrocene, C60·{Fe2+(η5 -C5H5)2•}2, was studied by ab initio calculations, single-crystal X-ray diffraction analysis, and Raman spectroscopy at pressures up to 5.3 GPa. The calculations based on high-pressure crystal structure data, performed by the fragment molecular orbital method and hybrid density functional level chemistry, show a pressure-dependent partial ionization of the C60 and Fe2+(η5 -C5H5)2• molecules. At pressures up to 2 GPa, the calculated charges of the two molecules nearest to the C60 ferrocenes grow equally, while at P > 2 GPa, the transferred charges are clearly different. The unequal charge transfer is due to the different orientations of the two neighboring ferrocene molecules with respect to a fullerene molecule cage. The Raman spectra of the complex show a peculiarity near 2 GPa in the pressure dependence of the frequency and bandwidth of the ferrocene intramolecular breathing mode associated with unequal charge transfer.

Computational Design of New N-Heterocyclic Silyl Pincer Fullerenes

A density functional theory study was performed to design new N-heterocyclic silyl pincer fullerenes based on the reactions of diaminofullerene with chlorosilanes SiHRCl2. Reaction energies of the formation of pincer fullerene ligands increased through the substitution of flanking arms with CH3 and phenyl groups. However, substituting hydrogen of SiH2 with methyl slightly increased the corresponding reaction energies; replacing hydrogen with phenyl group decreased the reaction energies of the considered pincer fullerenes. While the calculated electrophilicity values of the pincer fullerenes are larger than the electrophilicity values obtained for the fullerene derivatives, the substitution of hydrogen atoms of central SiH2 and PH2 did not has a noticeable impact on the electrophilicity values of the pincer fullerenes. The only exception was SiHPh(NCH2PH2)2C60. Natural bonding orbital analysis showed that the delocalization of electrons from the lone pairs of phosphorous atoms to the n* orbital of transition metal atoms was a key factor for stabilizing the considered complexes. The strongest interaction was due to the delocalization of electrons from lone pairs of phosphorous atoms in the flanking arms to the LP* of transition metals, which was followed by the delocalization of electrons of the Si-H σ* orbitals to the LP* of transition metals.

DFT computational study of trihalogenated aniline derivative’s adsorption onto graphene/fullerene/fullerene-like nanocages, X12Y12 (X = Al, B, and Y = N, P)

Adsorption of 2,4,6-tribromoaniline (BA), 2,4,6-trifluoroaniline (FA) and 2,4,6-trichloroaniline (CA) onto the surface of coronene/fullerene/fullerene-like nanocages was investigated by theoretical calculations. Due to the adsorption of BA/FA/CA, there are significant changes in chemical descriptors and nonlinear optical properties. Energy gap values of all nanoclusters are lowered, giving an increase in conductivity of complexes except for fullerene. All complex’s ultraviolet visible wavenumber is blue-shifted and especially for fullerene complex, the values are very high. The enhancement of Raman intensities shows that it is possible to design a nanocage sensor for detecting these compounds by surface-enhanced Raman scattering (SERS). Communicated by Ramaswamy H. Sarma

New Pd‐phosphorus ylide complexes based on FC60 as heterogeneous nano‐catalyst for H/D exchange reaction

In this account, new Pd(0) complexes of phosphorus ylides based on fullerene C60 (FC60) were synthesized and utilized as the first fullerene‐based heterogeneous nano‐catalysts for H/D exchange reaction. Four new palladacyclopropa‐[60]fullerene complexes 1–4, [(η2‐C60)Pd(Y1–4)2] (Y1 = PPh3CHC(O)C6H4‐p‐NO2, Y2 = PPh3CHC(O)C6H4‐p‐CH3, Y3 = (p‐tolyl)3P‐CHC(O)C6H4‐p‐NO2, and Y4 = (p‐tolyl)3P‐CHC(O)C6H4‐p‐CH3), were prepared through dissolving the related α‐keto stabilized phosphorus ylide in toluene solution in the presence of FC60 and Pd (dba)2 (dba = dibenzylideneacetone). All of the complexes were characterized using Nuclear magnetic resonance (NMR) (1H, 13C, and 31P), Infrared spectroscopy (IR), Ultraviolet‐visible spectroscopy (UV‐visible), fluorescence, Electrospray Ionisation Mass Spectrometry (ESI‐MS), and Energy‐dispersive X‐ray spectroscopy (EDX) spectroscopies, and scanning electron microscopy (SEM) and TEM techniques. The data proved that FC60 and two ylides were coordinated to Pd(0) center through two hexagons and two ylidic carbon atoms, respectively. An evaluation was also performed to compare the catalytic activity of synthesized Pd complex 1 and a conventional heterogeneous catalyst, 10% Pd on carbon, in H/D exchange reaction. The results indicate that the process of H/D exchange reaction in aromatic rings of benzoic acid derivatives progressed more efficiently by Pd complex 1.

Photoinduced electron transfer in non-covalent complexes of C60 and phosphangulene oxide derivatives.

Investigation of photoinduced electron transfer (PET) in a series of experimentally reported complexes of fullerene with phosphangulene oxides shows that the replacement of O atoms in the bridge of phosphangulene with S atoms promotes efficient and ultrafast ET from phosphangulene oxide to fullerene in PGOOSS⊃C60 and PGOSSS⊃C60 complexes. The results obtained can be useful for the development of photovoltaic devices based on phosphangulenes.

Photoinduced electron transfer in nano-Saturn complexes of fullerene.

The photoinduced electron transfer is studied computationally in several Saturn-shaped inclusion complexes of carbo-aromatic rings and C60 fullerene - C72⊃C60, C96⊃C60, C120⊃C60, and C168⊃C60. Analysis of their structural and electronic properties shows that the charge separation process is efficient in C120⊃C60 and C168⊃C60 where the host molecule resembles the conjugated [24]circulene unit. In contrast, the electron transfer is not feasible in the complexes of the oligophenylene-based rings C72⊃C60 and C96⊃C60.

Straightening properties of heterostructures based on fullerene and hybrid zinc complex

This work presents the results of using a new coordination compound C24H24N6O3Zn as a component for constructing heterostructures based on C60 fullerene. A procedure for the synthesis and preparation of a hybrid material is described. The formation of film structures from initial powder materials was carried out by pouring from a solution onto substrates using various types of solvents. The results of microscopy of the surfaces of the obtained films, as well as optical and luminescent properties are presented. Additionally, the optical band gap of the obtained films from hybrid materials was calculated. The addition of a zinc complex to a bond with fullerene suggests the appearance of a potential barrier at the interface between active layers. The resulting thin-film structures have rectifying light current-voltage characteristics. Additionally, the possibility of using the theoretical Poole--Frenkel model to explain the hopping conduction mechanism of the heterostructure under study is considered.

Porphyrin bearing phenothiazine pincers as hosts for fullerene binding via concave–convex complementarity: synthesis and complexation study

Free base porphyrin hosts, m-(PTZ)4-H2P and p-(PTZ)4-H2P, tethered with four phenothiazine moieties at the meso-position via a flexible ethoxy phenyl linker were synthesized and used for the selective complexation of fullerenes, C60 and C70.