Carbon-based Nanomaterials Research Articles

(Invited) Carbon Nanostructures for Targeted Delivery and Health Monitoring in Plants

To meet the demand for food and bioenergy of a rapidly growing global population requires novel and convergent approaches to enhance photosynthetic organism function. Nanotechnology is enabling the development of targeted and species independent tools for advancing plant bioengineering and precision agriculture.My research group has developed carbon nanotube-based sensors capable of real-time sensing of plant signaling molecules. These nanosensors enabled the creation of plant sentinels that communicate the health status of plants to electronic devices. Near-infrared (nIR) fluorescent single-walled carbon nanotubes (SWCNTs) were designed and interfaced with plant leaves to report hydrogen peroxide (H2O2), a key signaling molecule associated with the onset of plant stress. The sensor nIR fluorescence response (>900 nm) is quenched by H2O2 with selectivity against other stress-associated signaling molecules and within the plant physiological range (10–100 H2O2 μM). In vivo remote nIR imaging of H2O2 sensors enabled optical monitoring of plant health in response to stresses including UV-B light (−11%), high light (−6%), and a pathogen-related peptide (flg22) (−10%), but not mechanical leaf wounding (<3%). The sensor’s high biocompatibility was reflected on similar leaf cell death (<5%) and photosynthetic rates to controls without SWCNT. These optical nanosensors report early signs of stress and will improve our understanding of plant stress communication, provide novel tools for precision agriculture, and optimize the use of agrochemicals in the environment.We also developed targeted carbon-based nanomaterials as tools for precise chemical delivery (carbon dots, CDs) and gene delivery platforms (SWCNTs) to plant organelles (chloroplasts) and vasculature (phloem). A biorecognition approach of coating the nanomaterials with a rationally designed chloroplast targeting peptide improved the delivery of CDs with molecular baskets (TP-β-CD) for delivery of agrochemicals and of plasmid DNA coated SWCNT (TP-pATV1-SWCNT) from 47% to 70% and from 39% to 57% of chloroplasts in leaves, respectively. Plants treated with TP-β-CD (20 mg/L) and TP-pATV1-SWCNT (2 mg/L) had a low percentage of dead cells, 6% and 8%, respectively, similar to controls without nanoparticles, and no permanent cell and chloroplast membrane damage after 5 days of exposure. Orthogonally, the surfaces of carbon dot nanocarriers were functionalized with sucrose, enabling rapid and efficient foliar delivery into the plant phloem, a vascular tissue that transports sugars, signaling molecules, and agrochemicals through the whole plant. The chemical affinity of sucrose molecules to sugar membrane transporters on the phloem cells enhances the uptake of biocompatible carbon dots with β-cyclodextrin molecular baskets (suc-β-CD) that can carry a wide range of agrochemicals. The nanoparticle fluorescence emission properties allowed detection and monitoring of rapid translocation (<40 min) in the vasculature of wheat leaves by confocal and epifluorescence microscopy. The suc-β-CDs more than doubled the delivery of chemical cargoes into the leaf vascular tissue. The sucrose coating of nanoparticles approach enables unprecedented targeted delivery to roots with ≈70% of phloem-loaded nanoparticles delivered to roots.The use of plant biorecognition molecules mediated delivery provides an approach for guiding nanocarriers with their cargoes to plant organelles, cells and tissues and whole plants and engineering safer and efficient agrochemical and biomolecule delivery tools. Communication and actuation of plants mediated by nanosensors and targeted nanostructures can turn plants into technology and lead to a more precise and sustainable agriculture with reduced environmental impact.

(Invited) Synthesis and Functionalization of Nanographenes with Red to Near-Infrared Emission for Photonic Applications

Nanostructures of graphene demonstrate a wide range of optical, electronic, and magnetic properties depending on their size and chemical structures, which renders them promising as next-generation carbon-based nanomaterials, e.g., for nanoelectronics, spintronics, and photonics. However, it is challenging to accurately control the chemical structures while “cutting” graphene. To this end, large polycyclic aromatic hydrocarbons (PAHs) with nanoscale graphene structures are attracting a renewed attention as atomically precise nanographenes [1]. We have developed the synthesis of dibenzo[hi,st]ovalene (DBOV) as an unprecedented nanographene with high stability, strong red fluorescence, and stimulated emission, demonstrating the potential for organic lasers [2]. The functionalization of DBOV was achieved through regioselective bromination and Suzuki coupling, enabling the introduction of various substituents, for example fluoranthene imide (FAI) groups, inducing the red-shift of the emission to the near-infrared (NIR) region [3]. Different effects on the photophysical properties of the DBOV core have been observed by changing the peripheral functional groups. More recently, we have synthesized hexabenzoperihexacene (HBPH) with zigzag and fjord edges, which displayed high stability and NIR emission with maximum at ~800 nm [4]. Notably, HBPH could be made chiral by introducing bulky tert-butyl groups on the helical fjord edges, allowing the separation of the enantiomers and showing the circular dichroism responses up to 830 nm. These results provide a new insight into the structure-property relationship of such nanographenes and pave the way toward their photonic applications.[1] Paternò, G. M.; Goudappagouda,; Chen, Q.; Lanzani, G.; Scotognella, F; Narita A., Adv. Optical Mater. 2021, 9, 2100508.[2] Paternò, G. M.; Chen, Q.; Wang, X.-Y.; Liu, J.; Motti, S. G.; Petrozza, A.; Feng, X.; Lanzani, G.; Müllen, K.; Narita, A.; Scotognella, F., Angew. Chem. Int. Ed. 2017, 56, 6753–6757.[3] Paternò, G. M.; Chen, Q.; Muñoz-Mármol, R.; Guizzardi, M.; Bonal, V.; Kabe, R.; Barker, A. J.; Boj, P. G.; Chatterjee, S.; Ie, Y.; Villalvilla, J. M.; Quintana, J. A.; Scotognella, F.; Müllen, K.; Díaz-García, M. A.; Narita, A.; Lanzani, G., Mater. Horiz. 2022, 9, 393–402.[4] Xu, X.; Muñoz-Mármol, R.; Vasylevskyi, S.; Villa, A.; Folpini, G.; Scotognella, F.; Paternò, G. M.; Narita, A., Angew. Chem. Int. Ed. 2023, 62, e202218350.

Exploring New Carbon Allotropes and Nanographenes on Surfaces

The quest for planar sp2-hybridized carbon allotropes other than graphene has stimulated substantial research efforts because of their predicted unique mechanical, electronic, and transport properties. However, the syntheses of these nonbenzenoid networks remain challenging due to the lack of reliable protocols for generating nonhexagonal rings. We have developed various on-surface synthesis strategies by which straight polymer chains are linked to form the nonbenzenoid carbon networks. In this way, we synthesized biphenylene network, a new carbon allotrope with 4-6-8-membered rings, which is metallic already at very small dimensions. Similarly, we generated phagraphene nanoribbons, which are based on 5-6-7-membered rings.Acenes are another interesting class of carbon materials that have fascinated chemists and physicists due to their potential for use in organic electronic applications. We show the synthesis of tridecacene (13ac) and pentadecacene (15ac), the longest acenes known to date, via multistep single-molecule manipulation of suitable precursor molecules on Au(111). We find antiferromagnetic open-shell ground state electron configurations for both acenes. 15ac shows a low-bias spin-excitation feature, indicating a singlet-triplet gap of around 124 meV. Investigation of 15ac complexes with up to 6 gold atoms suggest considerable multiradical contributions to the electronic ground state of 15ac.Altering the electronic and magnetic properties of carbon-based nanomaterials can also be achieved by doping with heteroatoms. We present an access to a variety of nitrogen-containing 0D and 1D carbon nanostructures including planar and curved cycloarenes with different cavities as well as N-doped graphene nanoribbons.

Innovating Leishmaniasis Treatment: A Critical Chemist's Review of Inorganic Nanomaterials.

Leishmaniasis, a critical Neglected Tropical Disease caused by Leishmania protozoa, represents a significant global health risk, particularly in resource-limited regions. Conventional treatments are effective but suffer from serious limitations, such as toxicity, prolonged treatment courses, and rising drug resistance. Herein, we highlight the potential of inorganic nanomaterials as an innovative approach to enhance Leishmaniasis therapy, aligning with the One Health concept by considering these treatments' environmental, veterinary, and public health impacts. By leveraging the adjustable properties of these nanomaterials─including size, shape, and surface charge, tailored treatments for various diseases can be developed that are less harmful to the environment and nontarget species. We review recent advances in metal-, oxide-, and carbon-based nanomaterials for combating Leishmaniasis, examining their mechanisms of action and their dual use as standalone treatments or drug delivery systems. Our analysis highlights a promising yet underexplored frontier in employing these materials for more holistic and effective disease management.

Anhydride Photolysis on a Semiconductor Surface

The on-surface synthesis (OSS) method has facilitated the growth of diverse carbon-based nanomaterials, with the goal of integrating them into electronic devices. However, the reliance on metallic substrates in OSS restricts these materials' applications, necessitating strategies for transferring these materials into technological relevant substrates or direct synthesis on non-metallic surfaces, where the low absorption energies and lack of catalytic activity from the substrate complicate this approach. Addressing these limitations, we explore on-surface photochemistry as an alternative to thermally induced reactions, enabling controlled chemical processes at lower temperatures. While prior works have demonstrated light-induced reactions on metallic surfaces, where the hot electrons photogenerated from the metallic surface play a crucial role, synthesizing nanostructures directly on semiconducting or insulating surfaces through a purely intramolecular energy absorption remains challenging.The photolysis and pyrolysis of anhydrides has proven to be a suitable approach for the formation of arynes, as schematically shown in the Figure. Our study focuses on the selective photodissociation of maleic anhydride-containing precursors on a semiconductor surface (SnSe), unveiling their distinct photochemical behaviors. Specifically, tetraphenylphthalic anhydride (TPPA) undergoes successful photolysis on SnSe, forming tetraphenyl benzyne (TPBY) intermediates, and eventually, tetraphenyl benzene (TPBE) products. Furthermore, TPPA photolysis occurs efficiently also at room temperature, leading to the direct formation of TPBE. Contrastingly, benzo[ghi]perylene-1,2-dicarboxylic anhydride (BPA) possesses an extended pi-conjugated backbone and exhibits no photoactivity upon irradiation on the same semiconductor surface. Our calculations of TPPA and BPA excited states predict different behaviors, demonstrating the relationship between molecular structure, pi-conjugation, and photochemical reactivity, offering insights into the design principles for light-induced reactions on inert surfaces. Figure 1

Sensing of Pb (II) ion by micro and nanocarbon materials- influence of functionality and pi-electron density

In the aspect of pollution due to heavy metal ions, especially Pb (II) ions, there is an urgent need for simple, effective materials and processes for sensing the ions. The present study approaches the sensing of Pb (II) ions by non-metal (O, N and S) doped micro and nanoscale Carbon materials. The unique emission (Fluorescence) properties of the as-prepared doped samples of graphene oxides and Carbon Microspheres were tapped in the selective sensing process of nanomolar to the micromolar concentration of Pb (II) ions. The role-play of Carbon dimensionality, functionality and sp2 Carbon density (pi electron density) in the sensing mechanism was evaluated. The study provided an overview of fundamental aspects of heavy metal ion sensing by Carbon-based nanomaterials (CBNs).

Carbon-based nanomaterials: synthesis, types and fuel applications: a mini-review

Abstract Carbon is one of the most abundant minerals in the universe. The world’s energy needs are being unmet due to the exponential rise in population. Since its inception 20 years ago, carbon and its allotropes, including fullerenes, carbon nanotubes, and graphene, have been marketed as potential energy storage and generation materials. By solving important issues like accumulation and inadequate thermodynamic compatibility, carbon fiber, expanded graphite, and carbon nanotubes are promising functional materials that can be used to improve the performance of bipolar plates further. There are several potential uses for carbon-based nanomaterials (CBNMs) in the energy area. This mini-review provides an overview of the synthetic routes employed for producing CBNMs, categorizing them based on their types, elucidating their diverse applications in fuel energy systems, and emphasising the uses of CBNMs in energy. The advantages and disadvantages of several synthetic processes have been examined and compared. The types of CBNMs, like carbon nanotubes, graphene, carbon dots, and fullerenes, are explored in terms of their unique structural properties and fabrication methods. Furthermore, the utilization of CBNMs in fuel energy systems, such as fuel cells, energy storage devices, and catalysis, is comprehensively reviewed.

Unconventional strategies for liver tissue engineering: plant, paper, silk and nanomaterial-based scaffolds.

The paper highlights how significant characteristics of liver can be modeled in tissue-engineered constructs using unconventional scaffolds. Hepatic lobular organization and metabolic zonation can be mimicked with decellularized plant structures with vasculature resembling a native-hepatic lobule vascular arrangement or silk blend scaffolds meticulously designed for guided cellular arrangement as hepatic patches or metabolic activities. The functionality of hepatocytes can be enhanced and maintained for long periods in naturally fibrous structures paving way for bioartificial liver development. The phase I enzymatic activity in hepatic models can be raised exploiting the microfibrillar structure of paper to allow cellular stacking creating hypoxic conditions to induce in vivo-like xenobiotic metabolism. Lastly, the paper introduces amalgamation of carbon-based nanomaterials into existing scaffolds in liver tissue engineering.

Synergistic effects of graphene oxide, steel wire mesh and fibers on the impact resistance of preplaced aggregate concrete

Graphene Oxide (GO) has become a focal point of interest in civil engineering due to its exceptional mechanical and functional properties, making it a novel and promising carbon-based nanomaterial. However, the improvement in impact resistance of fibrous concrete by incorporating GO has not been explored until now. The novelty of this research is rooted in its pioneering analysis of the impact resistance of preplaced aggregate fibrous concrete, achieved through the combined incorporation of GO and steel wire mesh (SWM). This study uniquely investigates the effects of three different dosages of GO (0.1 %, 0.15 %, and 0.2 %) and three variations in the diameter of the steel wire mesh (50 mm, 100 mm, and 150 mm), alongside a fixed dosage of 3 % for steel fibers. Thirty-two distinct mixtures were prepared, with the steel wire mesh strategically placed at the midpoint of the specimen depth in each case. The specimens underwent drop-weight impact testing, with investigations conducted into their compressive strength, impact numbers related to cracking and failure, ductility index, and failure mode. The specimens incorporating a 0.2 % GO dosage with a 150 mm diameter of SWM displayed the highest observed cracking and failure impact numbers compared to those with 50 mm and 100 mm diameters of SWM. The observed increments ranged from 1.07 to 1.18 times for cracking and from 1.38 to 2.45 times for failure, compared to specimens containing 0.2 % GO without SWM. The identical specimens demonstrated the highest ductility values, ranging from 9.34 to 10.61. It is crucial to emphasize that adding GO does not induce an evolution from brittle to ductile failure of the specimen under impact loading, unlike the effect observed with steel wire mesh and steel fibre.

Interface-Mediated Neurogenic Signaling: The Impact of Surface Geometry and Chemistry on Neural Cell Behavior for Regenerative and Brain-Machine Interfacing Applications.

Nanomaterial advancements have driven progress in central and peripheral nervous system applications such as tissue regeneration and brain-machine interfacing. Ideally, neural interfaces with native tissue shall seamlessly integrate, a process that is often mediated by the interfacial material properties. Surface topography and material chemistry are significant extracellular stimuli that can influence neural cell behavior to facilitate tissue integration and augment therapeutic outcomes. This review characterizes topographical modifications, including micropillars, microchannels, surface roughness, and porosity, implemented on regenerative scaffolding and brain-machine interfaces. Their impact on neural cell response is summarized through neurogenic outcome and mechanistic analysis. The effects of surface chemistry on neural cell signaling with common interfacing compounds like carbon-based nanomaterials, conductive polymers, and biologically inspired matrices are also reviewed. Finally, the impact of these extracellular mediated neural cues on intracellular signaling cascades is discussed to provide perspective on the manipulation of neuron and neuroglia cell microenvironments to drive therapeutic outcomes.

5 MeV Si ion irradiation effects on structural and morphological properties of multiwalled carbon nanotubes

Carbon based nanomaterials (CBNs) such as multi walled carbon nanotubes (MWCNTs), graphene etc have attracted huge interest due to their widespread applications in contemporary nanotechnology. The ion bombardment is an important method which can be used for tuning of the structural and morphological properties of the CBNs. In the present work, we have carried out ion irradiation on MWCNTs (prepared by chemical vapour deposition method) with 5 MeV Si ions at different fluences ranging from 1 × 1014 to 5 × 1016 ions/cm2. The resulting structural and morphological modifications on the pristine MWCNTs have been characterized by using X-ray diffraction, Raman spectroscopy and field emission scanning electron microscopy. Results observed after successful characterization are compared with pristine sample results and we observed that the irradiation creates defects in MWCNTs and causes amorphized carbon nanomaterials depending on the fluence and energy deposited by energetic ions inside the MWCNTs.

Novel carbon quantum dots enhanced carbon nanotubes-graphene hybrid nanocomposite for VOCs detection

In recent years, researchers have shown a significant interest in exploring carbon-based nanomaterials for their potential applications in sensing technologies. This study introduces the development of an innovative composite material through the integration of quantum dots with carbon nanotubes and graphene. This nanohybrid composite serves as a sensing material for detecting ethanol at room temperature. The carbon quantum dots (CQD) used in this study were synthesized through a solvothermal process and integrated with carbon nanotubes (CNT) and graphene nanoplates (GNP) to investigate the synergistic effects on the composite's structure and its sensing properties. The resulting hybrid composite was applied as a sensitive film onto the surface of a quartz crystal microbalance (QCM) sensor. The hybrid nanocomposite-based sensor demonstrated significantly enhanced sensing sensitivity. At an ethanol concentration of 500 ppm, the CQD-enhanced CNT-GNP composite exhibited approximately 10- and 15-fold higher responses compared to CNT- and GNP-coated sensors, respectively. The response/recovery times of the CQD-enhanced CNT-GNP composite sensor were approximately 2/0.5 min, respectively. The sensor maintained reasonable repeatability and good recovery. The findings highlight the remarkable synergistic effects observed in the sensing performance of carbon-based nanohybrids, demonstrating the promising potential of this approach to enhance the sensitivity of such sensors.

Advanced functional materials as reliable tools for capturing food-derived peptides to optimize the peptidomics pre-treatment enrichment workflow.

Peptidomics strategies with high throughput, sensitivity, and reproducibility are key tools for comprehensively analyzing peptide composition and potential functional activities in foods. Nevertheless, complex signal interference, limited ionization efficiency, and low abundance have impeded food-derived peptides' progress in food detection and analysis. As a result, novel functional materials have been born at the right moment that could eliminate interference and perform efficient enrichment. Of note, few studies have focused on developing peptide enrichment materials for food sample analysis. This work summarizes the development of endogenous peptide, phosphopeptide, and glycopeptide enrichment utilizing materials that have been employed extensively recently: organic framework materials, carbon-based nanomaterials, bio-based materials, magnetic materials, and molecularly imprinted polymers. It focuses on the limitations, potential solutions, and future prospects for application in food peptidomics of various advanced functional materials. The size-exclusion effect of adjustable aperture and the modification of magnetic material enhanced the sensitivity and selectivity of endogenous peptide enrichment and aided in streamlining the enrichment process and cutting down on enrichment time. Not only that, the immobilization of metal ions such as Ti4+ and Nb5+ enhanced the capture of phosphopeptides, and the introduction of hydrophilic groups such as arginine, L-cysteine, and glutathione into bio-based materials effectively optimized the hydrophilic enrichment of glycopeptides. Although a portion of the carefully constructed functional materials currently only exhibit promising applications in the field of peptide enrichment for analytical chemistry, there is reason to believe that they will further advance the field of food peptidomics through improved pre-treatment steps.

Facile fabrication of fluorescent composite sensor based on carbon dots/ mesoporous silica nanospheres for sensitive detection of Hg(II) in cells

Mercury ion (Hg(II)) is one of the most toxic heavy metals in the environment and has seriously damaged human health. Based on this, we designed a novel fluorescence-enhanced carbon dots/mesoporous silica fluorescent composite (CDs/MSNs) fluorescent composite sensor for rapid and sensitive detection of Hg(II) in environmental and biological systems. Carbon dots (CDs) are one of the most promising carbon-based nanomaterials of the new generation, and we chose them as template molecules, and CDs were embedded in mesoporous silica nanospheres (MSNs) by hydrothermal method to form CDs/MSNs fluorescent composite with aggregation-induced emission enhancement (AIEE). Notably, the CDs/MSNs fluorescent composite has a yellow luminescence with a photoluminescence intensity several times higher than the original one, and have high stability, excellent selectivity, and good biocompatibility, which can realize the selective and sensitive detection of Hg(II) in the environment, with a limit of detection as low as 0.89 μM. The material can also be used as an effective luminescent biological probe for the detection of Hg(II) in cells. and these properties provide long-term practical applications of CDs/MSNs fluorescent composite in the fields of biological detection.

Carbon-Based Nanocomposite Membranes for Membrane Distillation: Progress, Problems and Future Prospects.

The development of an ideal membrane for membrane distillation (MD) is of the utmost importance. Enhancing the efficiency of MD by adding nanoparticles to or onto a membrane's surface has drawn considerable attention from the scientific community. It is crucial to thoroughly examine state-of-the-art nanomaterials-enabled MD membranes with desirable properties, as they greatly enhance the efficiency and reliability of the MD process. This, in turn, opens up opportunities for achieving a sustainable water-energy-environment nexus. By introducing carbon-based nanomaterials into the membrane's structure, the membrane gains excellent separation abilities, resistance to various feed waters, and a longer lifespan. Additionally, the use of carbon-based nanomaterials in MD has led to improved membrane performance characteristics such as increased permeability and a reduced fouling propensity. These nanomaterials have also enabled novel membrane capabilities like in situ foulant degradation and localized heat generation. Therefore, this review offers an overview of how the utilization of different carbon-based nanomaterials in membrane synthesis impacts the membrane characteristics, particularly the liquid entry pressure (LEP), hydrophobicity, porosity, and membrane permeability, as well as reduced fouling, thereby advancing the MD technology for water treatment processes. Furthermore, this review also discusses the development, challenges, and research opportunities that arise from these findings.

Microwave plasma enhanced chemical vapor deposited vertical carbon nanoflakes electrodes for electric double layer capacitors

BackgroundAs energy storage materials are in an urgent demand and carbon-based nanomaterials provided great potential for battery and supercapacitor. This study applied microwave plasma enhanced chemical vapor deposition (MPE-CVD) to deposit 3-dimensional carbon nanoflakes (CNFs) with distinguished surface area to prepare the electrodes for electric double layer capacitors (EDLCs). MethodsThe vertical growth of CNFs is driven by MPE-CVD using CH4 as precursor gas. The as-prepared CNFs on titanium plate (CNFs_700/Ti) was optimized by thickness and mass loading as function of the applied power. Raman spectroscopy and field emission scanning electron microscopy analyzed the properties and surface morphology of carbon. The electrochemical properties of the CNFs_700/Ti assembled as Swagelok or pouch cell were evaluated by cyclic voltammetry and galvanostatic charge/discharge for potential developments in supercapacitor. Significant findingsAn unprecedented rapid growth rate of CNFs, 180 μm/h, was dramatically accelerated due to MPE-CVD procedure, and could be applied as electrode for EDLCs. The mechanism of CNFs growth was elucidated based on the temperature measurements in reactor which relates closely to the CNFs growth rate, proved by thickness and mass loading of CNFs. The clarification of CNFs growth mechanism assists future developments of carbon-based materials in energy storage materials.

Evaluating the Impact of Sonication Process on Graphene Oxide Structural Properties

Graphene oxide (GO) is one of the members of carbon-based nanomaterials and can be featured as graphene structure decorated with various oxygenated functional groups. Recently, various methods have been found for producing carbon-based nanomaterials with enhanced efficiency in several applications. The chemical process involves oxidizing graphite to GO using a powerful oxidizing chemical. Hummers method is one of the most known and versatile method for the production of GO nanomaterials because of its ease of application, parameter controllability and high yield. This process enables graphite oxidation and exfoliation into single- or multi-layered GO sheets. Exfoliation, the separation of graphene or graphitic layers, is a critical process in GO synthesis. Since exfoliation separates multilayered graphite oxide flakes or particles, it forms single layer GO by forcing oxidizing agents or solvent molecules between layers. The sonication process can exfoliate the oxidized layers, resulting in the formation of GO structure when the exfoliated layers consist of only one or a few layers of carbon atoms. Therefore, sonication procedure is among the key parameters of Hummers method that influences the characteristics of GO-based nanomaterials. In this study, the impact of sonication duration time and power parameters on morphological and structural characteristics of GO development was examined. For this purpose, characterization studies were performed by using Scanning electron microscope (SEM), X-ray powder diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), UV-Vis spectroscopy and Raman spectroscopy analysis. The findings revealed that the increase in sonication power and time led to an increase in defects in the resulting GO structure.

Metal-Doping Strategy for Carbon-Based Sonosensitizer in Sonodynamic Therapy of Glioblastoma.

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor and known for its challenging prognosis. Sonodynamic therapy (SDT) is an innovative therapeutic approach that shows promise in tumor elimination by activating sonosensitizers with low-intensity ultrasound. In this study, a novel sonosensitizer is synthesized using Cu-doped carbon dots (Cu-CDs) for the sonodynamic treatment of GBM. Doping with copper transforms the carbon dots into a p-n type semiconductor having a bandgap of 1.58eV, a prolonged lifespan of 10.7 µs, and an improved electron- and hole-separation efficiency. The sonodynamic effect is efficiency enhanced. Western blot analysis reveals that the Cu-CDs induces a biological response leading to cell death, termed as cuproptosis. Specifically, Cu-CDs upregulate dihydrosulfanyl transacetylase expression, thereby establishing a synergistic therapeutic effect against tumor cell death when combined with SDT. Furthermore, Cu-CDs exhibit excellent permeability through the blood-brain barrier and potent anti-tumor activity. Importantly, the Cu-CDs effectively impede the growth of glioblastoma tumors and prolong the survival of mice bearing these tumors. This study provides support for the application of carbon-based nanomaterials as sonosensitizers in tumor therapy.

Antibacterial Interactions of Ethanol-Dispersed Multiwalled Carbon Nanotubes with Staphylococcus aureus and Pseudomonas aeruginosa.

Infectious diseases are acknowledged as one of the leading causes of death worldwide. Statistics show that the annual death toll caused by bacterial infections has reached 14 million, most of which are caused by drug-resistant strains. Bacterial antibiotic resistance is currently regarded as a compelling problem with dire consequences, which motivates the urgent identification of alternative ways of fighting bacteria. Various types of nanomaterials have been reported to date as efficient antibacterial solutions. Among these, carbon-based nanomaterials, such as carbon nanodots, carbon graphene oxide, and carbon nanotubes (CNTs), have been shown to be effective in killing a wide panel of pathogenic bacteria. With this study, we aim to provide additional insights into this topic of research by investigating the antibacterial activity of a specific type of multiwalled CNTs, with diameters from 50 to 150 nm, against two representative opportunistic pathogens, i.e., the Gram-positive bacterium Staphylococcus aureus and the Gram-negative bacterium Pseudomonas aeruginosa, both included among the top antibiotic-resistant pathogens. We also test the synergistic effect of CNTs with different antibiotics commonly used in the treatment of infections caused by S. aureus and/or P. aeruginosa. Additionally, a novel approach for quantitatively analyzing bacterial aggregation in brightfield microscopy images was implemented. This method was utilized to assess the effectiveness of CNTs, either alone or in combination with antibiotics, in dispersing bacterial aggregates. Finally, atomic force microscopy coupled with a newly devised image analysis pipeline was used to examine any potential morphological changes in bacterial cells following exposure to CNTs and antibiotics.

Methodology for fast testing of carbon-based nanostructured 3D electrodes in vanadium redox flow battery

Progress in material chemistry is manifested daily by the variety of prepared functional materials, often with nanodimensional structuring. The electrodes for vanadium redox flow batteries have been shown to benefit from incorporating nanostructured materials such as carbon nanotubes. However, the methods of such incorporation are far from optimal, relying mainly on physical deposition or insertion into a binder. Here, we describe a technique for integrating carbon-based rod-like nanomaterials into a vanadium redox flow battery and a methodology for fast nanomaterial performance testing. The technique is based on creating a fixed nanomaterial bed sandwiched between two graphite felt electrodes, forming a 3D flow-through electrode in the battery. Performing various positive and negative control experiments, we show the beneficial effect of a nanostructured bed on the primary battery characteristics obtained from short-term electrochemical experiments. We characterize carbon nanotubes exhibiting promising electrochemical behavior in vanadium electrolytes, as observed in our previous study. The load curves obtained from charge-discharge steps at various current densities and electrolyte flow rates revealed considerable differences in the performance of the tested materials, with few-walled carbon nanotubes reaching unsurpassable characteristics. At room temperature, with 50 %-SOC-working solutions and the highest tested linear velocity of 14.6 cm/min, the evaluated power density for this material reached values above 500 mW/cm2. For comparison, thermally treated graphite felt, used as a benchmark material, provided a power density of around 300 mW/cm2 under identical conditions. Although developed for vanadium redox flow batteries, the method enables testing tube-like and rod-like (nano-)materials for flow electrochemical systems.