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Sumio Iijima - One of the best experts on this subject based on the ideXlab platform.
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synthesis characterization and photoinduced charge separation of Carbon Nanohorn oligothienylenevinylene hybrids
Physical Chemistry Chemical Physics, 2016Co-Authors: Maria Vizuete, Masako Yudasaka, Sumio Iijima, Minfang Zhang, Maria J Gomezescalonilla, J L G Fierro, Myriam Barrejon, Pedro Atienzar, Hermenegildo Garcia, Fernando LangaAbstract:The covalent coupling between oligo(thienylenevinylenes) (nTVs) and Carbon Nanohorns (CNHs) has been investigated. The resulting nanohybrids have been characterized by a combination of several techniques, including thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM) and Raman spectroscopy. The photophysical properties of the new hybrids were investigated by steady-state and time-resolved spectroscopic techniques. A transient signal characterized by two kinetic regimes, one short decay within 0.5 μs corresponding to around 80% of the total signal and another much longer-lived decay of 10 μs, has been detected. The transient absorption spectra are characterized by a continuous absorption that increases in intensity towards shorter wavelengths, with a maximum at 430 nm. These transient signals have been assigned to the charge-separated state delocalized on CNHs based on the quenching behavior and by comparison with the photophysical properties of nTV in the absence and presence of quenchers. The photophysical behavior of covalent nTV–CNH conjugates with microsecond transients due to electrons and holes on CNHs contrasts with the absence of any transient for analogous nTV–C60 conjugates, for which charge separation was not observed at timescales longer than nanoseconds. The photochemical behavior of CNHs is believed to derive from the amphoteric (electron donor and acceptor) properties of CNHs and from the larger number of Carbon atoms (efficient delocalization) in CNHs compared with C60.
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photoinduced electron transfer in a Carbon Nanohorn c60 conjugate
Chemical Science, 2014Co-Authors: Maria Vizuete, Masako Yudasaka, Sumio Iijima, Maria J Gomezescalonilla, J L G Fierro, Kei Ohkubo, Shunichi Fukuzumi, Jeanfrancois Nierengarten, Fernando LangaAbstract:A nanohybrid combining two allotropic forms of Carbon, namely Carbon Nanohorns (CNH) and C60, has been obtained from a C60 derivative bearing a benzocrown ether subunit (crown–C60) and a CNH functionalized with NH3+ groups (CNH-sp-NH3+F−) through ammonium–crown ether interactions. The resulting CNH–C60 nanohybrid has been characterized by Raman and XPS spectroscopies, thermogravimetric analysis (TGA) and high-resolution transmission electron microscopy (HR-TEM). The photophysical properties of the CNH–C60 conjugate have been investigated in benzonitrile. Femtosecond laser flash photolysis measurements revealed the occurrence of an efficient electron transfer from the singlet excited state of the C60 moiety to the CNH with a rate constant of 6.5 × 1010 s−1 to produce a radical ion pair, which decayed by charge recombination with a lifetime of 1.0 ns to afford the triplet excited state of CNH-sp-NH3+F− and crown–C60. The two Carbon nanoforms play therefore complementary roles in the CNH–C60 conjugate, the CNH acting as an electron donor and C60 as an electron acceptor.
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structural modeling of dahlia type single walled Carbon Nanohorn aggregates by molecular dynamics
Journal of Physical Chemistry A, 2013Co-Authors: L Hawelek, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, Tomonori Ohba, A Brodka, John C Dore, Alex C Hannon, A BurianAbstract:The structure of dahlia-type single-walled Carbon Nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled Carbon Nanohorns with diameters of 20–50 A and a length of 400 A and an inner turbostratic graphite-like core with a diameter of 130 A. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.
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buffer gas optimization in co2 laser ablation for structure control of single wall Carbon Nanohorn aggregates
Carbon, 2012Co-Authors: Ryota Yuge, Masako Yudasaka, Takashi Yamaguchi, Sumio Iijima, Kiyohiko Toyama, Takashi ManakoAbstract:Abstract We succeeded in morphology-selective preparation of single-wall Carbon Nanohorn (SWCNH) aggregates by changing the buffer gas (760 Torr) in CO2 laser ablation of graphite: He for seed type, N2, Ar and Ne for dahlia type, and Kr for petal dahlia type. In Xe, aggregates of thin graphene sheets were the major product. The degree of graphitization increased with the mass number of the buffer gas. We specifically compared the structure and properties of SWCNHs prepared in N2 with those prepared in Ar for possible costs reduction for production by substituting N2 for Ar buffer gas. As-grown SWCNH aggregates prepared with N2 had smaller specific surface area than those prepared in Ar, however, this discrepancy almost completely disappeared with heat treatment at 1200 °C. By additional oxidation treatments, the specific surface area of the former became larger than the latter, and this is the largest surface area ever reported. We inferred that as-grown SWCNH aggregates (N2) had less number of petal-like graphenes, therefore after the removal of non-SWCNH Carbons by the heat treatment and/or oxidation, leading to the large surface area.
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Electronically modified single wall Carbon Nanohorns with iodine adsorption
Chemical Physics Letters, 2011Co-Authors: Fitri Khoerunnisa, Masako Yudasaka, Sumio Iijima, Hirofumi Kanoh, Tomonori Ohba, Tsutomu Itoh, Toshihiko Fujimori, Katsumi KanekoAbstract:Abstract Tailoring electronic properties of single wall Carbon Nanohorn (SWCNH) is expected to develop the application potential in various fields. SWCNH is efficiently modified with iodine molecules by liquid phase adsorption. The adsorption isotherm of iodine on SWCNH was Langmuirian with the saturated adsorption amount of 185 ± 10 mg g−1 (coverage 0.18), indicating a specific interaction between SWCNH and iodine. The DC electrical conductivity of SWCNH film prepared by dip-coating method increased with the iodine adsorption amount almost by a factor 10.
Masako Yudasaka - One of the best experts on this subject based on the ideXlab platform.
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Carbon Nanohorn liposome systems preformulation design and in vitro toxicity studies
Materials Science and Engineering: C, 2019Co-Authors: Natassa Pippa, Masako Yudasaka, Minfang Zhang, Christina Stangel, Ioannis Kastanas, Efstathia Triantafyllopoulou, Nikolaos Naziris, Dimitris Stellas, Costas DemetzosAbstract:Abstract In the present work, the convergence of two different drug delivery systems is investigated, namely the combination of Carbon Nanohorns (CNHs) and liposomes. Our effort initially included the synthesis of two conversely charged Carbon Nanohorns and their subsequent analysis through various methods. The study of their effect on the thermotropic behavior of artificial membranes provided an essential assistance for the upcoming liposome preparation, which were estimated for their physicochemical properties. The presence of CNHs alters the calorimetric parameters of the lipids. We also prepared CNHs:liposome systems. The characteristic morphology and secondary spherical superstructure of CNHs is retained in the chimeric materials, suggesting that the interactions with the liposomes do not alter the dahlia-flower-like aggregation of CNHs. Both CNHs-liposome systems exhibit a relatively small cellular cytotoxicity in vitro, tested in mouse embryonic fibroblasts. To summarize, we developed CNHs:liposome platforms with a complete knowledge of their thermotropic, physicochemical, morphological and nanotoxicological characteristics.
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Carbon Nanohorn/liposome systems: Preformulation, design and in vitro toxicity studies
Materials Science and Engineering: C, 2019Co-Authors: Natassa Pippa, Masako Yudasaka, Minfang Zhang, Christina Stangel, Ioannis Kastanas, Efstathia Triantafyllopoulou, Nikolaos Naziris, Dimitris Stellas, Costas Demetzos, Nikos TagmatarchisAbstract:Abstract In the present work, the convergence of two different drug delivery systems is investigated, namely the combination of Carbon Nanohorns (CNHs) and liposomes. Our effort initially included the synthesis of two conversely charged Carbon Nanohorns and their subsequent analysis through various methods. The study of their effect on the thermotropic behavior of artificial membranes provided an essential assistance for the upcoming liposome preparation, which were estimated for their physicochemical properties. The presence of CNHs alters the calorimetric parameters of the lipids. We also prepared CNHs:liposome systems. The characteristic morphology and secondary spherical superstructure of CNHs is retained in the chimeric materials, suggesting that the interactions with the liposomes do not alter the dahlia-flower-like aggregation of CNHs. Both CNHs-liposome systems exhibit a relatively small cellular cytotoxicity in vitro, tested in mouse embryonic fibroblasts. To summarize, we developed CNHs:liposome platforms with a complete knowledge of their thermotropic, physicochemical, morphological and nanotoxicological characteristics.
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Carbon nanotubes forming cores of fibrous aggregates of Carbon Nanohorns
Carbon, 2017Co-Authors: Ryota Yuge, Fumiyuki Nihey, Kiyohiko Toyama, Masako YudasakaAbstract:Abstract Cores of fibrous aggregates composed of radially assembled graphene-based single-walled Carbon Nanohorns, named as Carbon nanobrushes (CNBs), were observed using electron microscopes. As a result, a Carbon nanotube (CNT), probably single-layer structure, exposed from the CNBs was observed. From cross section images of CNBs, three round structures of about 2.5 nm diameters were also observed clearly at center part of single-walled Carbon Nanohorn (SWCNH) aggregate, which indicates the cross section of bundled single-walled CNTs. Therefore, we found that CNTs were localized at the core of CNBs. From these results, as for the formation mechanism of CNBs, it is supposed that the CNT functions as a template and SWCNHs radially gather on the CNT.
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synthesis characterization and photoinduced charge separation of Carbon Nanohorn oligothienylenevinylene hybrids
Physical Chemistry Chemical Physics, 2016Co-Authors: Maria Vizuete, Masako Yudasaka, Sumio Iijima, Minfang Zhang, Maria J Gomezescalonilla, J L G Fierro, Myriam Barrejon, Pedro Atienzar, Hermenegildo Garcia, Fernando LangaAbstract:The covalent coupling between oligo(thienylenevinylenes) (nTVs) and Carbon Nanohorns (CNHs) has been investigated. The resulting nanohybrids have been characterized by a combination of several techniques, including thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM) and Raman spectroscopy. The photophysical properties of the new hybrids were investigated by steady-state and time-resolved spectroscopic techniques. A transient signal characterized by two kinetic regimes, one short decay within 0.5 μs corresponding to around 80% of the total signal and another much longer-lived decay of 10 μs, has been detected. The transient absorption spectra are characterized by a continuous absorption that increases in intensity towards shorter wavelengths, with a maximum at 430 nm. These transient signals have been assigned to the charge-separated state delocalized on CNHs based on the quenching behavior and by comparison with the photophysical properties of nTV in the absence and presence of quenchers. The photophysical behavior of covalent nTV–CNH conjugates with microsecond transients due to electrons and holes on CNHs contrasts with the absence of any transient for analogous nTV–C60 conjugates, for which charge separation was not observed at timescales longer than nanoseconds. The photochemical behavior of CNHs is believed to derive from the amphoteric (electron donor and acceptor) properties of CNHs and from the larger number of Carbon atoms (efficient delocalization) in CNHs compared with C60.
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multifunctional Carbon Nanohorn complexes for cancer treatment
Chemistry-an Asian Journal, 2015Co-Authors: Svetlana A Chechetka, Masako Yudasaka, Benoit P Pichon, Minfang Zhang, Sylvie Begincolin, Alberto Bianco, Eijiro MiyakoAbstract:Multifunctional Carbon Nanohorn (CNH) complexes were synthesized using oxidized CNH, magnetite (MAG) nanoparticles, and polyethyleneimine (PEI). The ferromagnetic MAG nanoparticles were loaded onto CNH (MAG-CNH) using iron(II) acetate and subsequent heat treatment. Chemical functionalization of the MAG-CNH complexes with PEI improved their water-dispersibility and allowed further conjugation with a fluorophore. The application of an external magnetic field significantly intensified the targeted vectorization of CNH complexes into human cervical cancer (HeLa) cells. Following cell uptake, laser irradiation of the cells showed a significant enhancement in the photothermal effects of CNHs leading to cell death. We have confirmed that the photothermal properties and ferromagnetic characteristics of CNH complexes show efficient cell elimination. The present study is an essential step toward the development of an innovative cancer therapy and a highly sensitive detection of cancer cells at the single-cell level.
Katsumi Kaneko - One of the best experts on this subject based on the ideXlab platform.
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adsorption of water vapor on mesoporosity controlled singe wall Carbon Nanohorn
Colloids and Interface Science Communications, 2015Co-Authors: Elda Zoraida Pinasalazar, Katsumi KanekoAbstract:Abstract The adsorption mechanism of water vapor in hydrophobic Carbon mesopores is not clearly understood. Single wall Carbon Nanohorns (SWCNH) having different tube diameters in the range of 2 to 6 nm were oxidized at a lower temperature than the widely used temperature of 823 K. Oxidation at 633 K can selectively open thinner tubes of SWCNH and then the oxidation at different times can control the mesoporosity. The porosity of thus-oxidized SWCNH was evaluated from the nitrogen adsorption isotherms at 77 K. The pore volume ratio of micropores to mesopores was in the range of 0.50 to 0.90. The linear relationship between water adsorption amount and the pore volume of micropores and small mesopores (
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Toward in silico modeling of palladium–hydrogen–Carbon Nanohorn nanocomposites
Physical Chemistry Chemical Physics, 2014Co-Authors: Piotr Kowalczyk, Artur P. Terzyk, Piotr A. Gauden, Sylwester Furmaniak, Katsumi KanekoAbstract:We present the first in silico modeling of the Pd–H-single-walled Carbon Nanohorn nanocomposites. Temperature-quench Monte Carlo simulations are used to generate the most stable morphologies of Pd81 clusters (cluster sizes of ∼2 nm) deposited inside the morphologically defective single-walled Carbon Nanohorns (S. Furmaniak, A. P. Terzyk, K. Kaneko, P. A. Gauden, P. Kowalczyk, T. Itoh, Phys. Chem. Chem. Phys., 2013, 15, 1232–1240). The optimized Pd81-single-walled Carbon Nanohorn nanocomposites are next used in calculating the H binding energy distributions at 300 K. The most stable positions of H impurity in confined Pd81 clusters are identified, showing subsurface character of H absorption from the dilute H2 gas at 300 K. The H binding energy distribution on the Pd(100) open surface at 300 K is computed and compared with those corresponding to Pd81–single-walled Carbon Nanohorn nanocomposites. Finally, the impact of the Pd–H short-range order on the H binding energy is explored and critically discussed.
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surface to volume ratio of Carbon Nanohorn a crucial factor in co2 ch4 mixture separation
Chemical Physics Letters, 2014Co-Authors: Sylwester Furmaniak, Katsumi Kaneko, Piotr Kowalczyk, Artur P. Terzyk, Piotr A. Gauden, Tomonori OhbaAbstract:Using the first realistic model of single walled Carbon Nanohorn and molecular simulation data we show the 3D graphs relating the selectivity of CO2/CH4 separation with a surface to volume ratio of a Nanohorn, the total mixture pressure and the mole fraction of CO2 in the bulk phase. It is proved that surface to volume ratio is a crucial parameter determining the selectivity. Finally, the equation is proposed, making possible to predict the selectivity of a Nanohorn for separation of CO2/CH4 mixture.
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structural modeling of dahlia type single walled Carbon Nanohorn aggregates by molecular dynamics
Journal of Physical Chemistry A, 2013Co-Authors: L Hawelek, Masako Yudasaka, Sumio Iijima, Katsumi Kaneko, Tomonori Ohba, A Brodka, John C Dore, Alex C Hannon, A BurianAbstract:The structure of dahlia-type single-walled Carbon Nanohorn aggregates has been modeled by classical molecular dynamics simulations, and the validity of the model has been verified by neutron diffraction. Computer-generated models consisted of an outer part formed from single-walled Carbon Nanohorns with diameters of 20–50 A and a length of 400 A and an inner turbostratic graphite-like core with a diameter of 130 A. The diffracted intensity and the pair correlation function computed for such a constructed model are in good agreement with the neutron diffraction experimental data. The proposed turbostratic inner core explains the occurrence of the additional (002) and (004) graphitic peaks in the diffraction pattern of the studied sample and provides information about the interior structure of the dahlia-type aggregates.
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Superuniform Molecular Nanogate Fabrication on Graphene Sheets of Single Wall Carbon Nanohorns for Selective Molecular Separation of CO2 and CH4
Chemistry Letters, 2011Co-Authors: Tomonori Ohba, Hirofumi Kanoh, Katsumi KanekoAbstract:Superuniform nanosized gates (nanogates; 0.41 ± 0.02 nm in size) were donated on graphene sheets of single wall Carbon Nanohorn (SWCNH) particles by controlled oxidation. Super-uniform nanogate don...
Hirofumi Kanoh - One of the best experts on this subject based on the ideXlab platform.
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Superuniform Molecular Nanogate Fabrication on Graphene Sheets of Single Wall Carbon Nanohorns for Selective Molecular Separation of CO2 and CH4
Chemistry Letters, 2011Co-Authors: Tomonori Ohba, Hirofumi Kanoh, Katsumi KanekoAbstract:Superuniform nanosized gates (nanogates; 0.41 ± 0.02 nm in size) were donated on graphene sheets of single wall Carbon Nanohorn (SWCNH) particles by controlled oxidation. Super-uniform nanogate don...
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Electronically modified single wall Carbon Nanohorns with iodine adsorption
Chemical Physics Letters, 2011Co-Authors: Fitri Khoerunnisa, Masako Yudasaka, Sumio Iijima, Hirofumi Kanoh, Tomonori Ohba, Tsutomu Itoh, Toshihiko Fujimori, Katsumi KanekoAbstract:Abstract Tailoring electronic properties of single wall Carbon Nanohorn (SWCNH) is expected to develop the application potential in various fields. SWCNH is efficiently modified with iodine molecules by liquid phase adsorption. The adsorption isotherm of iodine on SWCNH was Langmuirian with the saturated adsorption amount of 185 ± 10 mg g−1 (coverage 0.18), indicating a specific interaction between SWCNH and iodine. The DC electrical conductivity of SWCNH film prepared by dip-coating method increased with the iodine adsorption amount almost by a factor 10.
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efficient production of h2 and Carbon nanotube from ch4 over single wall Carbon Nanohorn
Chemical Physics Letters, 2009Co-Authors: Yusuke Aoki, Masako Yudasaka, Sumio Iijima, Daisuke Noguchi, Hirofumi Kanoh, Tomonori Ohba, Koki Urita, Tsutomu Itoh, Katsumi KanekoAbstract:Abstract A new catalyst for efficient production of H 2 from CH 4 without CO 2 emission has been requested. We prepared highly-dispersed Pd nanoparticles on single wall Carbon Nanohorn (Pd-SWCNH) and on oxidized SWCNH (Pd-oxSWCNH) without an anti-aggregation agent. The Pd nanoparticle size on SWCNH and oxSWCNH determined by electron microscopy are around 2.5 and 2.7 nm, respectively. Each sample provides efficiently H 2 and hollow Carbon nanofibers through CH 4 decomposition. The H 2 release over the Pd-dispersed SWCNH samples starts from ca. 820 K and is quite large amount compared with a commercial Pd-activated Carbon.
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conductive and mesoporous single wall Carbon Nanohorn organic aerogel composites
Langmuir, 2007Co-Authors: Daisuke Noguchi, Masako Yudasaka, Sumio Iijima, Cheolmin Yang, Hirofumi Kanoh, Hideki Tanaka, Katsumi KanekoAbstract:Conductive and mesoporous single-wall Carbon Nanohorn/resorcinol−formaldehyde aerogel composites were fabricated by embedding organic resorcinol−formaldehyde aerogels with single-wall Carbon Nanohorns. Samples were characterized with transmission electron microscopy, field emission scanning electron microscopy, nitrogen adsorption at 77 K, and direct-current volume electrical conductivity measurement. It was demonstrated that these composites have important properties, such as controllable nanoporosity and high electrical conductivity in the range of 10-4 S m-1, which enables many potential applications.
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Conductive and mesoporous single-wall Carbon Nanohorn/organic aerogel composites.
Langmuir, 2007Co-Authors: Daisuke Noguchi, Masako Yudasaka, Sumio Iijima, Cheolmin Yang, Hirofumi Kanoh, Hideki Tanaka, Katsumi KanekoAbstract:Conductive and mesoporous single-wall Carbon Nanohorn/resorcinol−formaldehyde aerogel composites were fabricated by embedding organic resorcinol−formaldehyde aerogels with single-wall Carbon Nanohorns. Samples were characterized with transmission electron microscopy, field emission scanning electron microscopy, nitrogen adsorption at 77 K, and direct-current volume electrical conductivity measurement. It was demonstrated that these composites have important properties, such as controllable nanoporosity and high electrical conductivity in the range of 10-4 S m-1, which enables many potential applications.
Guobao Xu - One of the best experts on this subject based on the ideXlab platform.
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a kanamycin sensor based on an electrosynthesized molecularly imprinted poly o phenylenediamine film on a single walled Carbon Nanohorn modified glassy Carbon electrode
Analyst, 2017Co-Authors: Bingqian Li, Ze Song, Zhichao Zhang, Guobao XuAbstract:A single-walled Carbon Nanohorn (SWCNH) has been used to construct a molecularly imprinted electrochemical sensor for the first time. Kanamycin, a widely used aminoglycoside antibiotic, is used as a representative analyte to test the detection strategy. The kanamycin sensor was constructed by the electropolymerization of a molecularly imprinted poly-o-phenylenediamine film on a SWCNH modified glassy Carbon electrode. The sensor was investigated in the presence or absence of kanamycin by cyclic voltammetry to verify the changes in the redox peak currents of K3Fe(CN)6. The sensor exhibits a linear range of 0.1–50 μM with a detection limit of 0.1 μM. It also shows high recognition ability, indicating that the SWCNH-based molecularly imprinted sensor is promising.
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label free signal on atp aptasensor based on the remarkable quenching of tris 2 2 bipyridine ruthenium ii electrochemiluminescence by single walled Carbon Nanohorn
Chemical Communications, 2015Co-Authors: Wei Zhang, Wenjing Qi, Saima Hanif, Muhammad Saqib, Guobao XuAbstract:The quenching of electrochemiluminescence by single-walled Carbon Nanohorn has been demonstrated for the first time. Moreover, a sensitive, label-free, and signal-on electrochemiluminescence ATP aptasensor was developed using single-walled Carbon Nanohorn as both quencher and scaffold.
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simultaneous voltammetric determination of dihydroxybenzene isomers at single walled Carbon Nanohorn modified glassy Carbon electrode
Sensors and Actuators B-chemical, 2014Co-Authors: Ling Zhang, Jianming Zhao, Guobao XuAbstract:Abstract The voltammetric behaviors of dihydroxybenzene isomers were studied at the single-walled Carbon Nanohorn modified glassy Carbon (SWCNH-modified GC) electrode. Compared with the bare electrode, SWCNH-modified GC electrode has stronger electrocatalytic activity for the oxidation of dihydroxybenzenes with the increase in peak current and the decrease in peak separation (ΔEp) between the anodic and cathodic peaks. Furthermore, the three isomers can be determined simultaneously and sensitively by using linear sweep voltammetry at the SWCNH-modified GC electrode. For hydroquinone, catechol, and resorcinol, the oxidation peak currents are linear with the concentrations in the range of 0.5–100 μM, 0.5–100 μM, and 1.0–100 μM, respectively. Their detection limits at a signal-to-noise ratio of 3 are 0.1 μM, 0.2 μM, and 0.5 μM, respectively. These results make SWCNH-modified GC electrode a promising candidate for the simultaneous determination of isomers.
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simultaneous electrochemical determination of uric acid dopamine and ascorbic acid at single walled Carbon Nanohorn modified glassy Carbon electrode
Biosensors and Bioelectronics, 2009Co-Authors: Haijuan Li, Guobao XuAbstract:Single-walled Carbon Nanohorn modified glassy Carbon electrode (SWCNH-modified GCE) was first employed for the simultaneous determination of uric acid (UA), dopamine (DA), and ascorbic acid (AA). The SWCNH-modified GCE displayed excellent electrochemical catalytic activities. The oxidation overpotentials of UA, DA, and AA decrease significantly and their oxidation peak currents increase dramatically at SWCNH-modified GCE. Linear sweep voltammetry (LSV) was used for the simultaneous determination of UA, DA, and AA in their ternary mixture. The peak separations between UA and DA, and DA and AA are large up to 152 mV and 221 mV, respectively.
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Single-walled Carbon Nanohorn as new solid-phase extraction adsorbent for determination of 4-nitrophenol in water sample
Talanta, 2009Co-Authors: Haijuan Li, Guobao XuAbstract:Abstract Single-walled Carbon Nanohorn (SWCNH) was developed as new adsorbent for solid-phase extraction using 4-nitrophenol as representative. The unique exoteric structures and high surface area of SWCNH allow extracting a large amount of 4-nitrophenol over a short time. Highly sensitive determination of 4-nitrophenol was achieved by linear sweep voltammetry after only 120 s extraction. The calibration plot for 4-nitrophenol determination is linear in the range of 5.0 × 10−8 M–1.0 × 10−5 M under optimum conditions. The detection limit is 1.1 × 10−8 M. The proposed method was successfully employed to determine 4-nitrophenol in lake water samples, and the recoveries of the spiked 4-nitrophenol were excellent (92–106%).