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High-performance bilayer counter electrodes (BCEs) for dye-sensitized solar cell (DSSC) applications are gaining considerable attention. In this study, MoS2 /single-walled carbon nanohorn (SWCNHs) BCEs were fabricated by ultrasonic-spray-assisted electrochemical deposition. The BCEs exhibited superior electrocatalytic activity, confirmed through CV, Tafel plots, and electrochemical impedance spectroscopic studies. The fabricated MoS2 /SWCNH-based DSSCs exhibited an impressive photovoltaic power conversion efficiency of 9.48 %, which is higher than the performance of cells with Pt-containing CEs (8.64 %). The simple and reliable growth strategy for bilayer film CEs provides a new route for the preparation of cost-effective and high-performance catalytic BCEs for renewable energy applications involving Pt-free DSSCs.

Oxidized single walled carbon nanohorns (ox-SWCNH) were electrodeposited onto gold microelectrode arrays in conjunction with poly(3,4-ethylenedioxythiophene) (PEDOT) and polystirenesulfonate (PSS), and the properties of the new composite material for neural recording and stimulation were assessed. PEDOT/ox-SWCNH composites were compared with films prepared with one of the most notorious carbonaceous material in this field, the oxidized multi-walled Carbon Nanotubes (ox-MWCNT). The PEDOT/ox-SWCNH exhibited superior charge transfer capability, reflecting greater electroactive surface, as confirmed by SEM and EIS characterizations. As a consequence, a charge injection limit of 11.6mC/cm⁠2 was observed for the new composite, which is higher than the one of PEDOT/ox-MWCNT (8.7mC/cm⁠2). Having confirmed comparable neural recording performance, the PEDOT/ ox-SWCNH composite results very promising for improving therapeutic electrical stimulation in the central and peripheral nervous systems.

In the present study, SWCNH-COOH and SWCNH-TETA were fabricated using single-walled carbon nanohorns (SWCNHs) via carboxylation and grafting with triethylenetetramine (TETA) for uranium (VI) ion [U(VI)] removal. The morpho-structural characterization of as-prepared adsorbing materials was performed by transmission electron microscopy, X-ray diffractometry, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Several parameters including the pH value of the aqueous solutions, contact time, temperature, and U(VI) concentration were used to evaluate the sorption efficiency of SWCNH-COOH and SWCNH-TETA. The Langmuir isotherm model could well represent the as-obtained adsorption isotherms, and the kinetics was successfully modeled by pseudo-second-order kinetics in the adsorption process. The maximum adsorption capacity of SWCNH-TETA was calculated as 333.13 mg/g considering the Langmuir isotherm model. Thermodynamic studies showed that adsorption proved to be a spontaneous endothermic process. Moreover, SWCNH-TETA exhibited excellent recycling performance and selective adsorption of uranium. Furthermore, the possible mechanism was investigated by XPS and density functional theory calculations, indicating that the excellent adsorption was attributed to the cooperation capability between uranium ions and nitrogen atoms in SWCNH-TETA. This efficient approach can provide a strategy for developing high-performance adsorbents for U(VI) removal from wastewater.

Photochromic molecules derived from bioresources and their hybrids with various carbon nanomaterials always resulted in devices with outstanding performance. Among different carbon nanomaterials su...

Recently, substantial focus has made in the development of cost effective Pt-free dye sensitized solar cells (DSSCs). In this article we report a potential, Pt-free, carbon based nanocomposite as counter electrode catalyst for dye sensitized solar cells. Graphene oxide (GO) was made into reduced graphene oxide (SSrGO) by irradiating with light (Xe source). Suspension of SSrGO in DMF was spray coated onto fluorine doped tin oxide (FTO) coated glass substrate, followed by spray coat of single walled carbon nanohorns (SWCNH) suspension in DMF. SSrGO and SWCNH coated FTO glass substrate was investigated as an effective Pt-free composite counter electrode (CE) for DSSC and also showed the comparable catalytic activity with Pt. The test cell reveals power conversion efficiency (PCE) of 8.27%, whereas the DSSC module exhibited a PCE of 5.18%. By using the fabricated DSSC module, an electric motor (15 mW) was operated both in indoor and outdoor light conditions. The procedures followed in this work pave a way for the easy fabrication of composite CE towards transparent DSSC modules and further the integration of the DSSC module with the standard Si solar cell is of great potential for various real-time application.

We report for the first time the chromatographic study of n-alcohols (from methanol to butanol) adsorption on single walled carbon nanohorn (SWCNH). Using measured temperature dependence of adsorption isotherms (373–433 K) the isosteric adsorption enthalpy is calculated and compared with the data reported for a graphite surface. It is concluded that a graphite surface is more homogeneous, and the enthalpy of adsorption on SWCNHs at zero coverage correlates well with molecular diameter and polarizability, suggesting leading role of dispersive interactions, i.e., no heteroatoms presence in the walls of SWCNH structures. Next using modern DFT approach we calculate the energy of n-alcohols interactions with a graphene sheet and with a single nanocone finally proposing a more realistic—double nanocone model. Obtained results suggest alcohols entrapping between SWCNH with OH groups located toward nanocones ends, leading to the conclusions about very promising future applications of SWCNHs in catalytic reactions with participation of n-alcohols.

The low density of porous carbon nanomaterials for supercapacitor electrodes has limited their widespread application, despite their ultra-high gravimetric capacitance. In this work, we successfully prepared highly densified composite electrodes of graphene and single-walled carbon nanohorns (SWCNHs) using a simple spray-drying method that is suitable for mass production. To prepare the high-density composite electrodes, water-based mixtures of oxidized SWCNHs (NHOs) and graphene oxides (GOs) were spray-dried in heated air; after spray-drying, GOs dispersed in water were agglomerated in spherical clusters containing NHO nanoparticles. The reduced spray-dried GO/NHO (rS-GO/NHO) composite electrodes exhibited an extremely high bulk density of 1.23 g·cm−3, which is almost double that of commercial activated carbon (AC) and reduced NHO (r-NHO) electrodes, and three times higher than that of rS-GO electrodes. Of the materials tested, the rS-GO/NHO composite electrode had the highest volumetric capacitance (80 F·cm−3 at 1 mA·cm−2) and a low sheet resistance (0.005 Ω· sq.−1), which are far superior to those of commercial AC (57 F·cm−3 at 1 mA·cm−2 and 0.293 Ω·sq.−1, respectively), without the need for a conductive material, such as carbon black. We expect that these high-density graphene/SWCNH composite electrodes with high volumetric capacitances can be substituted for commercial AC materials in energy storage devices, such as supercapacitors.

A glassy carbon electrode (GCE) modified with single-walled carbon nanohorns (SWCNH) and zein (ZE), a prolamin type-protein find in maize, for the differential pulse adsorptive cathodic stripping voltammetric determination of fenitrothion (FT) is proposed. The proposed film was characterized by scanning electron microscopy, cyclic voltammetry and electrochemical impedance spectroscopy. Regarding the electrochemical characterization, comparing the results obtained by cyclic voltammetry and electrochemical impedance spectroscopy, the modified electrode (SWCNH-ZE/GCE) showed an electroactive surface area 3 times higher and faster electron transfer kinetic than bare GCE. By using differential pulse adsorptive cathodic stripping voltammetry and SWCNH-ZE/GCE the analytical curve exhibited a linear response ranging of 9.9 × 10−7 to 1.2 × 10−5 mol L−1, with a limit of detection of 1.2 × 10−8 mol L−1. The proposed sensor was successfully applied for the determination of FT pesticide in natural water and orange juice samples. Moreover, the electrochemical sensor showed good repeatability and reproducibility arising from the excellent film stability, suggesting that the proposed architecture has broad potential for applications in sensing and biosensing.

γ-valerolactone (GVL) is a fine chemical which is widely used as a green solvent, a fuel additive and a green fuel. It can be produced from lignocellulosic biomass and its derivatives, such as methyl levulinate (ML) via catalytic hydrogenation reaction. In this work, novel hybrid materials of Ni nanoparticles and single-walled carbon nanohorns (Ni/CNHs) synthesized from gas-injected arc-in-water (GI-AIW) method was used as catalysts for producing GVL from ML. Effect of surface modification, oxidation and reduction of Ni/CNHs on their catalytic activity was investigated. For comparison of catalytic activities, Ni on other carbon supports prepared by the conventional wet impregnation and unsupported Ni catalysts were examined. X-ray diffractometry (XRD), transmission electron microscopy (TEM), field-emission scanning electron microscopy (FE-SEM), N2 sorption, thermogravimetric analysis (TGA), Hydrogen-temperature-programmed reduction (H2-TPR), and Fourier Transform Infrared (FT-IR) spectroscopy were employed for elucidating different characteristics of all examined catalysts. It was found that reduced oxidized Ni/CNHs exhibited the highest catalytic performance with 96% conversion of ML, 90% yield, and 93% selectivity of GVL.

In this study, a dual-type responsive electrochemical biosensor was developed for the quantitative detection of α2,6-sialylated glycans (α2,6-sial-Gs), a potential biomarker of tumors. The gold nanorods (AuNRs), which exhibited great specific surface area, as well as good biocompatibility, was synthesized by the way of seed growth method. Furthermore, a biotin-streptavidin (biotin-SA) system was introduced to improve the immunoreaction efficiency. Accordingly, a label-free biosensor was fabricated based on AuNRs-SA for the quick detection of α2,6-sial-Gs by recording the signal of differential pulse voltammetry (DPV). Furthermore, to expand the ultrasensitive detection of α2,6-sial-Gs, a carboxylated single-walled carbon nanohorns/sulfur-doped platinum nanocluster (c-SWCNHs/S-PtNC) was synthesized for the first time as a novel signal label, which showed an excellent catalytic performance. The usage of c-SWCNHs/S-PtNC could significantly amplify the electrochemical signal recorded by the amperometric i-t curve. Herein, a sandwich type biosensor was constructed by combining the AuNRs-SA on the electrode and c-SWCNHs/S-PtNC (signal amplifier). The label-free biosensor possessed a linear range from 5 ng mL−1 to 5 μg mL−1 with a detection limit of 0.50 ng mL−1, and the sandwich-type biosensor possessed a wide linear range from 1 fg mL−1 to 100 ng mL−1 with a detection limit of 0.69 fg mL−1. Furthermore, the biosensor exhibited excellent recovery and stability, indicating its potential for use in actual samples.

Among various carbon materials, nitrogen doped single walled carbon nanohorns (N-SWCNHs) have a unique structure of clustered conical cages (2–5 nm in diameter and 40–50 nm in length) arranged in dahlia, bud and seed-like configurations. Each conical cage has five pentagons at their tips which act as potential reactive site with their own distinct chemistry. We exploited these reactive sites of N-SWCNHs by preferentially growing germanium nanocrystals (Ge NCs) onto their conical tips using oleylamine as a mild reducing agent. Therefore, Ge decorated N-SWCNHs (Ge@N-SWCNHs) composite was used, for the first time, as active anode material for lithium ion batteries providing high and stable capacity of 1285 mAh/g at 0.1C after 100 cycles. Our results show that preferential growth of Ge Nanocrystals (NCs) on the tips of N-SWCNHs not only allows high utilization of active material but prevents the aggregation of Ge NCs after multiple cycling. Finally, we highlight the potential role of N-SWCNHs as cheap and industrially scalable conductive host for next generation lithium ion batteries.

Single-walled carbon nanohorns (SWCNHs) was utilized as an ion-to-electron transducer to fabricate all-solid-state ion-selective electrodes (ISE) for the first time. To evaluate the performance of developed SWCNHs-based calcium ISE, various electrochemical experiments were carried out. A Nernstian response (29.69 ± 0.24 mV/decade, R2 = 0.9996) was acquired across a broad linear range between 10−6 and 10−2 M, and the detection limit of 10−6.1 M was achieved in the meantime. Additionally, water layer test and reversed chronopotentiometry were used to estimate the long-term and short-term stability of SWCNHs-based ISE, respectively, indicating SWCNHs is capable of enhancing potential stability on account of its hydrophobicity. Furthermore, a SWCNHs-based reference electrode (RE) was fabricated by directly coating a photo-polymerised reference membrane (RM) onto a SWCNHs modified electrode. Results demonstrated that the SWCNHs-based RE exhibited slight potential fluctuation for common ions with different charges over a wide concentration range of calibration. Based on these superior results, an integrated all-solid-state SWCNHs-based potentiometric sensing device combined SWCNHs-based ISE and SWCNHs-based RE was constructed for detecting calcium, which shows a Nernstian response with a slope of 27.14 mV/decade. This developed electrode in the aid of SWCNHs exhibits fast response as well as outstanding potential stability, making it extreme promising for routine sensing application.

In this study, we report an electrochemical study based on nanocellulose (NC) and single-walled carbon nanohorns (SWCNH). SWCNH and NC ensure large surface area, good conductivity, high porosity and chemical stability, becoming attractive for electrodes. The materials were characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), Scanning Electron Micrograph (SEM), Transmission electron microscopy (TEM), dynamic light scattering (DLS) and zeta potential. Using XRD and FTIR it was possible to observe particular characteristics of NC and SWCNH. The presence of dahlia-like assemblies on the NC surface was observed by MEV and TEM. Then, we investigated the electrochemical behavior of NC-SWCNH, which showed the excellent results when it was used guanine and adenine, as proof of concept, by using cyclic and linear sweep voltammetry (LSV). LSV was also employed for simultaneous detection resulting in limits of detection of 1.7 × 10−7 mol L−1 and 1.4 × 10−6 mol L−1, for guanine and adenine, respectively. In addition, the proposed electrode was applied for determination of both bases in synthetic human serum and fish sperm. We demonstrate that it is possible to use NC, a renewable material, in conducting thin films with SWCNH, and due to simplicity in the preparation and high conductivity, this new thin film could be extended for others electrochemical purposes such as sensing and biosensing.

Application of carbon nanomaterials to near-infrared light-mediated phototherapy has attracted great interest. However, their practical use in biological systems is severely limited by their poor water dispersibility, inevitable adsorption of plasma proteins, and their single therapeutic function. Herein, we prepared a phycocyanin (PC)-functionalized single-walled carbon nanohorns (PC@SWNHs) hybrid, where PC is used to preform a protein corona around the SWNHs through non-covalent interface interactions. In the PC@SWNHs, the preformed PC corona effectively improves the water dispersibility of the SWNHs and protects them from plasma protein adsorption. In addition, the excellent photodynamic activity of PC overcomes the inability of SWNHs to generate reactive oxygen species. The SWNHs not only give the hybrid a photothermal therapy (PTT) function, but they also enhance the photostability of PC. These characteristics of the PC@SWNHs are confirmed by in vitro and in vivo experiments, where synergistic photodynamic therapy (PDT)/PTT growth inhibition of tumors is achieved. The PC@SWNHs also act as a photoacoustic/thermal imaging agent to visualize the in vivo treatment process. Hence, this work not only paves the way to use the complementarity between SWNHs and proteins for multifunctional cancer theranostics, but it also allows for a better understanding of bio–nano interface interactions between them.

We firstly reveal the unique tendency in the capacitance of an electric double layer capacitor (EDLC) made of single-walled carbon nanohorns (SWCNHs), where there is an optimized value of specific surface area (SSA) to achieve the high capacitance value at a high charge-discharge rate. As a result, in the experimental observation, SWCNHs treated by oxidation in air at 550 °C can exhibit 963.4 m2/g of SSA and 286.6 F/g of EDLC capacitance, whereas the ones treated at 500 °C can exhibit 797.5 m2/g and 316.4 F/g at a high scan rate of 100 mV/s, although the SSA-capacitance relation seems ordinal at 5 mV/s. This result is against a common sense that the higher the SSA, the higher the EDLC capacitance. This unique relationship between the SSA of SWCNHs and the capacitance can be explained by consideration of the hierarchical pore structures of SWCNHs, including the internal mesopore zone and inner-core micropore zone, and the diffusion limitation of ionic species in these different structures. These pores are interlinked via the nanowindows opened by the oxidation treatment, and the nanowindow-link can be enhanced by temperature elevation from 500 to 550 °C, while the superficial mesopore can be partially destroyed at 550 °C.

Single-walled carbon nanohorns (SWNHs) have been shown to be effective photothermal enhancers and drug delivery agents for potential cancer therapy, particularly for the eradication of bladder cancer lesions. In this study, the potential for SWNHs to serve as nanotheranostic vehicles is demonstrated through simultaneous delivery of the chemotherapeutic cisplatin from SWNH cone interiors and imaging of the nanoparticle transport to tumor cells using conjugated quantum dots (QDs). Following the formation of cisplatin-modified SWNH-QD (SWNH-QD + cis) hybrids, their characterization by scanning and transmission electron microscopy (STEM, TEM), energy dispersive spectroscopy (EDS), and dynamic light scattering (DLS) were performed to characterize the composite nanoparticles. Drug release profiles and 50% inhibitory concentration (IC50) determination showed that QDs do not hinder the therapeutic ability of SWNHs. In addition, the hybrids were trackable over the course of a 3 day period, which indicates that internalized SWNHs can continue to deliver therapy after removal of the nano-agents from the cell culture. This unique SWNH hybrid can successfully be used as an imaging agent to study nanoparticle transport and consequently the delivery of a therapeutic to the targeted cancer cells.

Fibrous aggregates of single-walled carbon nanohorns (carbon nanobrushes: CNBs) were prepared by CO2 laser ablation of an iron-containing carbon target with rotations under nitrogen atmosphere and ambient pressure. The rotation speed of the target and concentration of iron contained in it were controlled so as to increase the yield of CNBs. As a result, many CNBs were obtained at a rotation speed of 1 rpm and iron concentration above 1 at. %, although the samples still contained spherical single-walled carbon nanohorn aggregates (CNHs). The sheet resistivity of the samples containing both CNBs and CNHs decreased with the CNB content, which indicates that the CNBs formed a good conducting path. By forming supercapacitor electrodes, the capacitances of mixture of CNBs and CNHs, CNHs, and activated carbon were similar, i.e., 20, 21, and 23 F/g, respectively, at 0.1 A/g. However, the capacitance of the mixture of CNBs and CNHs at a discharge current of 5 A/g was about 1.4 and 6 times higher than that of the CNHs and activated carbon. These newly discovered CNBs should definitely increase the advantages of nanocarbon in various fields, especially in electronic devices.

The generation of hydrogen from water represents an important task towards a carbon neutral economy. Within this context, the preparation of hybrid electrodes merging the versatility of solid-state porous substrates and the catalytic ability and tunability of molecular complexes represents a great challenge. In the present work, we report on the preparation of hybrid cathodes for the hydrogen evolution reaction (HER) through an unprecedented combination of single-walled carbon nanohorns (SWCNHs) and two novel cobalt(II) polypyridine complexes based on the tris(2-pyridylmethyl)amine (TPMA) ligand scaffold. Suitable pyrene groups are introduced in the ligand framework in different positions to provide a way for direct anchoring onto the carbonaceous substrate by exploiting non-covalent π–π interactions. The present systems behave as competent cathodes for the HER in neutral aqueous solution with overpotentials of η ∼ 0.5 V and stable current densities (within 1 h electrolysis) up to −0.50 mA cm−2, whose exact values depend on the catalyst used and are mainly related to the respective loading on the electrode surface. In both cases, hydrogen evolution is detected under continuous electrolysis for up to ca. 12 h leading to maximum turnover numbers (TONs) of 4700 and 9180 molH2 molCo−1 for the two different complexes. The progressive deactivation under electrolytic conditions is mainly ascribed to leaching of the metal centre from the polydentate ligand, likely occurring from the competent catalytic intermediates involved in the HER.

Organic&ndash, inorganic ternary nanohybrids consisting of oxidized-single walled carbon nanohorns-SnO2-polyvinylpyrrolidone (ox-SWCNH/SnO2/PVP) with stoichiometry 1/1/1 and 2/1/1 and ox-SWCNH/ZnO/PVP = 5/2/1 and 5/3/2 (all mass ratios) were synthesized and characterized as sensing films of chemiresistive test structures for ethanol vapor detection in dry air, in the range from 0 up to 50 mg/L. All the sensing films had an ox-SWCNH concentration in the range of 33.3&ndash, 62.5 wt%. A comparison between the transfer functions and the response and recovery times of these sensing devices has shown that the structures with ox-SWCNH/SnO2/PVP = 1/1/1 have the highest relative sensitivities of 0.0022 (mg/L)&minus, 1, while the devices with ox-SWCNH/SnO2/PVP = 2/1/1 have the lowest response time (15 s) and recovery time (50 s) for a room temperature operation, proving the key role of carbonic material in shaping the static and dynamic performance of the sensor. These response and recovery times are lower than those of &ldquo, heated&rdquo, commercial sensors. The sensing mechanism is explained in terms of the overall response of a p-type semiconductor, where ox-SWCNH percolated between electrodes of the sensor, shunting the heterojunctions made between n-type SnO2 or ZnO and p-type ox-SWCNH. The hard&ndash, soft acid&ndash, base (HSAB) principle supports this mechanism. The low power consumption of these devices, below 2 mW, and the sensing performances at room temperature may open new avenues towards ethanol sensors for passive samplers of environment monitoring, alcohol test portable instruments and wireless network sensors for Internet of Things applications.

We investigated the electrochemical performance of single-walled carbon nanohorns (SWCNHs) for use as supercapacitor electrodes. For the first time, we used acid-treatment for oxidation of SWCNHs and hole creation in their structure. A detailed study was performed on the correlation between the oxidation of SWCNHs via acid treatment and variable acid treatment times, the structural properties of the oxidized carbon nanostructures, and the specific capacitance of the SWCNH electrodes. We showed that simple functionalization of carbon nanostructures under controlled conditions leads to an almost 3-fold increase in their specific capacitance (from 65 to 180 F g−1 in 0.1 M H2SO4). This phenomenon indicates higher accessibility of the surface area of the electrodes by electrolyte ions as a result of gradual opening of the SWCNH internal channels.

The low toxicity, high surface area, and ease of functionalisation of carbon nanohorns (CNH) makes them attractive systems for cellular imaging, diagnostics and therapeutics. However, challenges remain for the biomedical translation of these and other nanomaterials. A significant task is tuning the surface chemistry to achieve optimal cellular interactions. Herein, we combine real-time fluorescent imaging of nanoparticle cellular uptake and real-time differential interference contrast (DIC) imaging of extracellular media to monitor a) nanoparticle/nanoparticle and b) nanoparticle/cell interactions for CNHs covalently modified with an OFF/ON near-IR dye, the fluorescence of which is switched OFF in extracellular environments and triggered upon cellular internalisation. CHN samples modified with different loadings of the hydrophobic dye are taken as a simple model of drug-loaded nanoparticle systems. The punctate fluorescence suggests the CNHs are delivered to lysosomes and other vesicles of the endocytic pathway. DIC imaging highlights the competition that exists for many particle types, between extracellular aggregation and cellular internalization, the efficiency of which would be dependent upon the amount of fluorophore loading. The results of this study illustrate how complementary real-time imaging methods together with physicochemical characterisation can be used to address the challenges involved in optimising nanoparticle/cell interactions for biomedical applications. Irish Research Council Science Foundation Ireland University College Dublin

A novel amplified electrochemiluminescence (ECL) immunoassay based on single-walled carbon nanohorns (SWCNHs) labels and enzymatic biocatalytic precipitation (BCP) was proposed for the detection of neuron-specific enolase (NSE) for the first time. In this system, the dimercaptosuccinic acid stabilized CdTe (DMSA-CdTe) quantum dots (QDs) as ECL emitter showed excellent ECL behavior and then employed as the NSE antibody (Ab1) immobilization film for the subsequent sandwich-type Ab1-Ag affinity interactions. Improved sensitivity was achieved through using the SWCNHs effectively to expand the amount of secondary antibody (Ab2) and horseradish peroxidase (HRP) loading. In addition to the much enhanced steric hindrance, compared with the single HRP-Ab2, the presence of plentiful HRP would further stimulate the BCP onto the electrode surface for signal amplification, concomitant to the BCP products absorption that lowered ECL intensity. As a result of the multisignal amplification in this ECL immunosensor, it possessed excellent analytical performance. The target NSE could be detected from 1 × 10−9 g L−1 to 1 × 10−3 g L−1 with a detection limit of 4.4 × 10−10 g L−1.

Tumor combination therapy using nano formulations with multimodal synergistic therapeutic effects shows great potential for complete ablation of tumors. However, targeting tumor metastases with nano structures is a major obstacle for therapy. Therefore, developing a combination therapy system able to target both primary tumors and their metastases at distant sites with synergistic therapy is desirable for the complete eradication of tumors. To this end, a dual chemodrug-loaded theranostic system based on single walled carbon nanohorns (SWNHs) is developed for targeting both primary breast tumors and their lung metastases. Methods: SWNHs were first modified simultaneously with poly (maleic anhydride-alt-1-octadecene) (C18PMH) and methoxypolyethyleneglycol-b-poly-D, L-lactide (mPEG-PLA) via hydrophobic-hydrophobic interactions and π-π stacking. Then cisplatin and doxorubicin (DOX) (2.9:1 molar ratio) were sequentially loaded onto the modified nanohorns in a noninterfering way. After careful examinations of the release profiles of the loaded drugs and the photothermal performance of the dual chemodrug-loaded SWNHs, termed SWNHs/C18PMH/mPEG-PLA-DOX-Pt, the dual drug chemotherapeutic and chemo-photothermal synergetic therapeutic effects on tumor cells were evaluated. Subsequently, the in vivo behavior and tumor accumulation of the drug-loaded SWNHs were studied by photoacoustic imaging (PAI). For chemo-photothermal therapy of tumors, 4T1 tumor bearing mice were intravenously injected with SWNHs/C18PMH/mPEG-PLA-DOX-Pt at a dose of 10 mg/kg b.w. (in SWNHs) and tumors were illuminated by an 808 nm laser (1W/cm2 for 5 min) 24 h post-injection. Results: DOX and cisplatin were loaded onto the modified SWNHs with high efficiency (44 wt% and 66 wt%, respectively) and released in a pH-sensitive, tandem and sustainable manner. The SWNHs/C18PMH/mPEG-PLA-DOX-Pt had a hydrodynamic diameter of 182 ± 3.2 nm, were highly stable in physiological environment, and had both dual drug chemotherapeutic (CI = 0.439) and chemo-photothermal synergistic antitumor effects (CI = 0.396) in vitro. Moreover, the dual drug-loaded SWNHs had a long blood half-life (10.9 h) and could address both the primary breast tumors and their lung metastases after intravenous administration. Consequently, chemo-photothermal combination therapy ablated the primary tumors and simultaneously eradicated the metastatic lung nodules. Conclusion: Our study demonstrates that SWNHs/C18PMH/mPEG-PLA-DOX-Pt is highly potent for chemo-photothermal combination therapy of primary tumors and cocktail chemotherapy of their metastases at a distant site.

Poly(amic-acid) modified single-walled carbon nanohorns (PAA/SWCNH-COOH) contained dual-functional groups (amide and carboxyl) were synthesized by in-situ polymerization and used for the elimination of uranium (VI). It was found that the adsorption capacity of SWCNH-COOH increased significantly after grafting PAA chains, and the theoretical monolayer adsorption capacity of PAA/SWCNH-COOH could reach 216.0 mg/g. The adsorption capacity of this material could remain up to 90% of the initial value after 5 times of reuse. Moreover, PAA/SWCNH-COOH has an excellent adsorption selectivity, which could be attributed to the synergistic adsorption effects between amide and carboxyl groups. To further study the interaction mechanism between uranium ions and the adsorbents, the quantum chemical calculations were performed using DFT method. The simulation results show that both amide and carboxyl groups have a strong interaction with uranium ions, which ensures the high adsorption capacity of this material. This research proved that the PAA/SWCNH-COOH is a promising adsorption material for removing uranium from wastewater and it also sheds a light on the interaction mechanism between bifunctional adsorbents and uranium ions.

Ultrasonic-assisted liquid-phase exfoliation is one of high-efficiency strategies for preparing two-dimensional (2D) materials. Herein, we report a facile and green synthesis of the phosphorene (BP) obtained from bulk black phosphorus crystal in the ionic liquid (IL) 1-ethyl-3-methylimidazoliumtetrafluoroborate ([EMIm]BF4) through ultrasonic-assisted liquid-phase exfoliation under the continuous nitrogen atmosphere. To gain more insight, the morphology and composition of the as-prepared BP were characterized. The prepared BP showed satisfactory stability in ambient condition containing oxygen and water. In the following, single walled carbon nanohorn (SWCNH) was selected to enhance electrocatalytic capacity and endow oxidase-like (nanozyme) characteristics, which was further applied for electrochemical sensing of 5-hydroxytryptamine (5-HT). Derivative techniques were employed for treating voltammograms to obtain sharper and narrower voltammetric peak, transform asymmetric peak into much more symmetrical peak, reduce background interference, eliminate personal error and directly read the accurate value. Machine learning (ML) model based on artificial neural network (ANN) algorithm as an artificial intelligence approach is adopted to establish smart sensing system via the relationship between concentrations and currents in comparison with traditional linear regression model. The BP-IL-SWCNH nanozyme sensor displayed excellent electrocatalytic ability for second-order derivative voltammetric smart analysis of 5-HT range from 0.3 to 115 µM under optimal conditions.

A novel CdTe quantum dots - single walled carbon nanohorns (CdTe-SWCNHs) nanocomposite was synthesized via a one-pot method for photoelectrochemical (PEC) aptasensing detection of streptomycin (STR). The CdTe-SWCNHs nanocomposite shows 3.2-times amplified PEC activity in comparison with CdTe quantum dots (QDs). By using aptamers as recognition element and CdTe-SWCNHs as photoactive species, a PEC aptasensor was fabricated for the high sensitive and selective detection of STR. Under the optimized conditions, the as-fabricated PEC aptamer sensor exhibits a linear response ranging from 0.1 nM (0.15 μg kg −1 ) to 50 nM (72.85 μg kg −1 ) with a detection limit ( S / N = 3) of 0.033 nM (0.05 μg kg −1 ). The aptasensor has successfully applied for the determination of streptomycin in honey sample, which provides a new method for detection of streptomycin.

Ochratoxin A (OTA), is one of the most commonly found mycotoxins in food. It is primarily produced by Aspergillus ochraceus and Penicillium verrucosum. OTA can causes serious damages to liver and kidney, increases the teratogenicity, and has been considered as a potential carcinogen (group 2 B). In this study, we demonstrated a new detection system for the detection of OTA using fluorescence biosensing according to an anti-OTA aptamer and fluorescence quencher using single-walled carbon nanohorns (SWCNHs). In the presence of OTA, the OTA-specific aptamer underwent the conformation change from a random coil to an antiparallel G-quadruplex. The latter one was resistant to being adsorbed onto SWCNHs, leading to the pertection of the fluorescence of SYBR Gold. As a result, the remained fluorescent intensities correlated with the concentrations of OTA. The detection limit of OTA was 2.3 ng/ml, meanwhile the linear detection range was 5–500 ng/ml, with a satisfactory linear correlation (R2 = 0.992) of the fluorescence intensity and the logarithm of OTA concentrations. The aptasensor was subjected to quantify the concentration of OTA in red wine samples. As a result, this label-free aptasensor was suitable for the test of OTA in food samples.