Reconstitution of the membrane protein OmpF into biomimetic block copolymer–phospholipid hybrid membranes

• Matthias Bieligmeyer,
• Franjo Artukovic,
• Stephan Nussberger,
• Thomas Hirth,
• Thomas Schiestel and
• Michaela Müller

Beilstein J. Nanotechnol. 2016, 7, 881–892, doi:10.3762/bjnano.7.80

• molecular weight of the block copolymers. At low voltages, the channel conductance of OmpF in 1 M KCl was around 2.3 nS. In line with these experiments, integration of OmpF was also revealed by impedance spectroscopy. Our results indicate that blending synthetic polymer membranes with phospholipids allows

• to retain the polymeric character of the membranes, the amount of lipid used was limited to 10 mol %. Eventually, membranes were analyzed using confocal laser scanning microscopy, voltage clamp measurements and impedance spectroscopy. Results and Discussion Block copolymer synthesis Poly(1,4-isoprene

• ). Pure DPhPC vesicles prepared under similar conditions were significantly smaller than those composed of PIPEO and DPhPC (Figure 2B). They revealed completely different morphologies than the lipopolymersomes. Using impedance spectroscopy, we attempted to gain insight into the electrical properties of

Reorientation of single-wall carbon nanotubes in negative anisotropy liquid crystals by an electric field

• Amanda García-García,
• Ricardo Vergaz,
• José F. Algorri,
• Gianluigi Zito,
• Teresa Cacace,
• Antigone Marino,
• José M. Otón and
• Morten A. Geday

Beilstein J. Nanotechnol. 2016, 7, 825–833, doi:10.3762/bjnano.7.74

• orientation of the liquid crystal molecules. Moreover, impedance spectroscopy suggests a nonnegligible anchoring force between the CNTs and the liquid crystal molecules. Keywords: Anchoring; carbon nanotubes; impedance; liquid crystal; negative anisotropy; Raman spectroscopy; reorientation; single-wall CNTs

Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform

• M. Fátima Barroso,
• M. Alejandra Luna,
• Juan S. Flores Tabares,
• Cristina Delerue-Matos,
• N. Mariano Correa,
• Fernando Moyano and
• Patricia G. Molina

Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58

• electrochemical impedance spectroscopy or square wave voltammetry [22][23]. It is known that antibodies can be immobilized onto AuNPs without losing their biological properties [24][25]. Thus, the covalent immobilization of vesicles decorated with AuNPs on a gold surface could increase the amount of immobilized

Mismatch detection in DNA monolayers by atomic force microscopy and electrochemical impedance spectroscopy

• Maryse D. Nkoua Ngavouka,
• Pietro Capaldo,
• Elena Ambrosetti,
• Giacinto Scoles,
• Loredana Casalis and
• Pietro Parisse

Beilstein J. Nanotechnol. 2016, 7, 220–227, doi:10.3762/bjnano.7.20

• mismatches. The second strategy exploits the change in capacitance at the interface between an ssDNA-functionalized gold electrode and the solution due to the hybridization process in a miniaturized electrochemical cell. Through electrochemical impedance spectroscopy measurements on extended ssDNA self

• microRNAs or in genomic DNA. Keywords: atomic force microscopy; DNA monolayers; electrochemical impedance spectroscopy; hybridization; mismatches; Introduction Most current technologies for genotyping and sequencing are based on DNA hybridization, exploiting the high grade of selectivity due to the unique

• cell. In a previous work we demonstrated the ability to follow the hybridization of perfectly matched sequences in real time through electrochemical impedance spectroscopy (EIS) measurements on extended ssDNA self-assembled monolayers (SAMs) [27]. Here we successfully tested EIS for the detection of

Synthesis and applications of carbon nanomaterials for energy generation and storage

• Marco Notarianni,
• Jinzhang Liu,
• Kristy Vernon and
• Nunzio Motta

Beilstein J. Nanotechnol. 2016, 7, 149–196, doi:10.3762/bjnano.7.17

Charge injection and transport properties of an organic light-emitting diode

• Peter Juhasz,
• Juraj Nevrela,
• Michal Micjan,
• Miroslav Novota,
• Jan Uhrik,
• Lubica Stuchlikova,
• Jan Jakabovic,
• Ladislav Harmatha and
• Martin Weis

Beilstein J. Nanotechnol. 2016, 7, 47–52, doi:10.3762/bjnano.7.5

• investigated by steady-state current–voltage technique and impedance spectroscopy at various temperatures to obtain activation energies of charge injection and transport processes. Good agreement of activation energies obtained by steady-state and frequency-domain was used to analyze their contributions to the

• identification of major bottleneck of charge injection and transport. Keywords: activation energy; impedance spectroscopy; organic light-emitting device; Introduction Since the discovery of organic electroluminescent (EL) materials such as tris(8-hydroxyquinolinato)aluminum(III) (Alq3), organic light-emitting

• steady-state current density–voltage characteristics [5][6], or measurement in time- or frequency-domain, such as transient currents [7] and impedance spectroscopy [8][9]. Furthermore, the measurements can be extended by the temperature dependence of electrical properties which reveal the thermally

A single-source precursor route to anisotropic halogen-doped zinc oxide particles as a promising candidate for new transparent conducting oxide materials

• Daniela Lehr,
• Markus R. Wagner,
• Johanna Flock,
• Julian S. Reparaz,
• Clivia M. Sotomayor Torres,
• Alexander Klaiber,
• Thomas Dekorsy and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2015, 6, 2161–2172, doi:10.3762/bjnano.6.222

• longitudinal optical phonon–plasmon coupling and describes the interaction of collective oscillating free carriers (plasmons) with LO phonons [80]. Consequently, the concentration of free carriers increases with Cl doping. The dielectric properties of thin ZnO1−xClx pellets were investigated with impedance

• spectroscopy. In the Nyquist plot in Figure 6 the imaginary part of the impedance is plotted as a function of the real part. For materials having resistive and capacitive components a series of two semicircles usually occurs in the Nyquist plot. The semicircle in the high frequency region is assigned to grain

Electrochemical behavior of polypyrrol/AuNP composites deposited by different electrochemical methods: sensing properties towards catechol

• Celia García-Hernández,
• Cristina García-Cabezón,
• Cristina Medina-Plaza,
• Fernando Martín-Pedrosa,
• Yolanda Blanco,
• José Antonio de Saja and
• María Luz Rodríguez-Méndez

Beilstein J. Nanotechnol. 2015, 6, 2052–2061, doi:10.3762/bjnano.6.209

• incorporated in the Ppy films was higher when using CP than that when using CA. In turn, using cogeneration, the amount of nanoparticles incorporated was higher than using trapping. Electrochemical impedance spectroscopy Electrochemical impedance spectroscopy (EIS) can provide information about the

• . Electrochemical impedance spectroscopy (EIS) characterization EIS was performed in a 0.1 mol/L KCl solution with a frequency range from 105 to 0.1 Hz and a signal amplitude of 10 mV, at a working potential of 0.0 V. Tests of the voltammetric sensors The Ppy and Ppy/AuNPs films were used as working electrodes in

Optimized design of a nanostructured SPCE-based multipurpose biosensing platform formed by ferrocene-tethered electrochemically-deposited cauliflower-shaped gold nanoparticles

• Wicem Argoubi,
• Maroua Saadaoui,
• Sami Ben Aoun and
• Noureddine Raouafi

Beilstein J. Nanotechnol. 2015, 6, 1840–1852, doi:10.3762/bjnano.6.187

• and concentration of the ferrocene derivatives have been studied using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). Selectivity and specificity tests have been also performed in the presence of potentially interfering substances to

• competitive proteins using a panel of electrochemical techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). Application of the two platforms for the detection of hIgG and H2O2 respectively in human serum and in honey are presented

• is ideal to obtain a nanostructured surface with high density of well-dispersed nanoparticles and a surface of about 7.8 × 10−3 cm2 corresponding to a 1 mm diameter bulk gold electrode. Study by electrochemical impedance spectroscopy Gold is a more conductive material than carbon, so the

Surface engineering of nanoporous substrate for solid oxide fuel cells with atomic layer-deposited electrolyte

• Sanghoon Ji,
• Waqas Hassan Tanveer,
• Wonjong Yu,
• Sungmin Kang,
• Gu Young Cho,
• Sung Han Kim,
• Jihwan An and
• Suk Won Cha

Beilstein J. Nanotechnol. 2015, 6, 1805–1810, doi:10.3762/bjnano.6.184

• via impedance spectroscopy To investigate the effects of BEC thickness on the individual resistances, electrochemical impedance spectroscopy (EIS) data were obtained for the Cell-A and Cell-B. Before comparing the EIS data for two kinds of cells, the EIS curves obtained under different direct current

• (left side) and 320 (right side) nm-thick BECs; (B) transmission electron microscopic image for 80 nm pore AAO supported 320 nm-thick BEC. Tafel plots, measured at 500 °C, for the Cell-A and Cell-B. Electrochemical impedance spectroscopy analysis results, measured at 500 °C, at bias voltage of 0.1 V for

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

• Philipp Adelhelm,
• Pascal Hartmann,
• Conrad L. Bender,
• Martin Busche,
• Christine Eufinger and
• Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

Electrical response of liquid crystal cells doped with multi-walled carbon nanotubes

• Amanda García-García,
• Ricardo Vergaz,
• José F. Algorri,
• Xabier Quintana and
• José M. Otón

Beilstein J. Nanotechnol. 2015, 6, 396–403, doi:10.3762/bjnano.6.39

• significant depending on the degree of reorientation of the MWCNTs. The impedance behavior of MWCNT-doped and undoped LC cells has been studied by impedance spectroscopy. The results are shown in Cole–Cole plots of the imaginary (Z″) versus the real part (Z′) of the impedance. In these plots, also known as

• efficient aligning surface, PEDOT:PSS has a remarkably higher conductivity than polyimide, what is essential to keep electric continuity across the layer. Characterization method: driving waveform Impedance spectroscopy customarily employs sufficiently small voltage signals so that the system response is

Kelvin probe force microscopy in liquid using electrochemical force microscopy

• Liam Collins,
• Stephen Jesse,
• Jason I. Kilpatrick,
• Alexander Tselev,
• M. Baris Okatan,
• Sergei V. Kalinin and
• Brian J. Rodriguez

Beilstein J. Nanotechnol. 2015, 6, 201–214, doi:10.3762/bjnano.6.19

• electronic charge and z is the ion valence. At low biases (Vdc < kT/e ≈ 25 mV) and in the absence of Faradaic reactions, this RC time is the relevant timescale of the transient response, e.g., in high-frequency impedance spectroscopy experiments or induced charge electrokinetics, where high-frequency

Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating

• Christina Rosman,
• Sebastien Pierrat,
• Marco Tarantola,
• David Schneider,
• Eva Sunnick,
• Andreas Janshoff and
• Carsten Sönnichsen

Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257

• polymer induced a reduction by 30% and 40%, respectively, which is absent for the carboxy-terminated polymer. Furthermore, interface-sensitive impedance spectroscopy (electric cell–substrate impedance sensing, ECIS) was employed in order to investigate the micromotility of cells added to substrates

• properties of the coating agent and its reactive group. The impact on surfactant-induced cell behavior was investigated in more detail by interface-sensitive impedance spectroscopy (electric cell–substrate impedance sensing, ECIS). Studies on the uptake and influence on metabolic activity with respect to

Low cost, p-ZnO/n-Si, rectifying, nano heterojunction diode: Fabrication and electrical characterization

• Vinay Kabra,
• Lubna Aamir and
• M. M. Malik

Beilstein J. Nanotechnol. 2014, 5, 2216–2221, doi:10.3762/bjnano.5.230

• Equations 4–6 [9][10] as follows: where Vbi is the built-in voltage, Xn and Xp are the depletion width for the n- and p-side, and εn and εp are the dielectric constants of n-Si and p-ZnO, respectively. The dielectric constants εp and εn were found to be 7 and 11.7, respectively, as derived from impedance

• spectroscopy [9][10]. The depletion width on the n-side is found to be shorter than on the p-side because the carrier concentration of n-Si is higher than p-ZnO, which is supported by the Hall effect results. The calculated values of these various diode parameters using Equations 4–6 are listed in Table 1

Growth and structural discrimination of cortical neurons on randomly oriented and vertically aligned dense carbon nanotube networks

• Christoph Nick,
• Sandeep Yadav,
• Ravi Joshi,
• Christiane Thielemann and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2014, 5, 1575–1579, doi:10.3762/bjnano.5.169

• stimulate neural activity. CNTs do have a high capacity and low impedance, e.g., compared to IrO2 which is widely used as electrical interface for cells, as has been manifested by cyclic voltammetry and impedance spectroscopy [9]. Thus CNTs allow to minimise the stimulation voltage as well as the electrode

Optical modeling-assisted characterization of dye-sensitized solar cells using TiO₂ nanotube arrays as photoanodes

• Jung-Ho Yun,
• Il Ku Kim,
• Yun Hau Ng,
• Lianzhou Wang and
• Rose Amal

Beilstein J. Nanotechnol. 2014, 5, 895–902, doi:10.3762/bjnano.5.102

• parameters of the DSSCs, electrochemical impedance spectroscopy (EIS) offers valuable information. Figure 4 shows the Bode phase plots and the Nyquist plots obtained from electron transfer at the TiO2 and electrolyte interface under a solar simulator of AM 1.5. Figure 4a shows the negative shift of the

• for about 40 min. The absorbance measurement was performed using UV–vis spectrophotometer (Cary 300, Varian). The electrochemical impedance spectroscopy (EIS) measurements were performed by illuminating the DSSCs with a AM 1.5 solar simulator calibrated at 100 mW·cm−2 at open-circuit conditions

Enhancement of photocatalytic H₂ evolution of eosin Y-sensitized reduced graphene oxide through a simple photoreaction

• Weiying Zhang,
• Yuexiang Li,
• Shaoqin Peng and
• Xiang Cai

Beilstein J. Nanotechnol. 2014, 5, 801–811, doi:10.3762/bjnano.5.92

• photoreaction. This further indicates the restoration of the sp2 π-conjugated network for RGO after the photoreaction. Due to restoration of the sp2 π-conjugated network in RGOx, its conductivity is expected to increase [42]. To verify this enhancement, the electrochemical impedance spectroscopy (EIS) of GO

• -resolution TEM (HRTEM) images were taken on a JEOL JEM-2010 (TEM) equipped with an energy dispersive spectrometer (EDS). Electrochemical impedance spectroscopy (EIS) was measured on an IVIUMSTAT electrochemical workstation (Netherlands). The electrochemical experiments were performed in a 3-compartment cell

Electrochemical and electron microscopic characterization of Super-P based cathodes for Li–O₂ batteries

• Mario Marinaro,
• Santhana K. Eswara Moorthy,
• Jörg Bernhard,
• Ludwig Jörissen,
• Margret Wohlfahrt-Mehrens and
• Ute Kaiser

Beilstein J. Nanotechnol. 2013, 4, 665–670, doi:10.3762/bjnano.4.74

• (trifluoromethane)sulfonimide lithium salt (LiTFSI)/tetraglyme electrolyte were investigated by galvanostatic cycling and electrochemical impedance spectroscopy measurements. Ex-situ X-ray diffraction and scanning electron microscopy were used to evaluate the formation/dissolution of Li2O2 particles at the cathode

• side during the operation of Li–O2 cells. Keywords: aprotic electrolyte; impedance spectroscopy; Li–O2 batteries; scanning electron microscopy; Introduction The development of new types of electrochemical power sources is nowadays considered a key factor for further development of hybrid and fully

• electrolyte. The electrochemical behaviors of the batteries were investigated by galvanostatic cycling and electrochemical impedance spectroscopy. The physico–chemical investigation of the lithium-oxide phases that form and dissolve at the cathode side upon discharge and charge of Li–O2 batteries has been

Novel composite Zr/PBI-O-PhT membranes for HT-PEFC applications

• Mikhail S. Kondratenko,
• Igor I. Ponomarev,
• Marat O. Gallyamov,
• Dmitry Y. Razorenov,
• Yulia A. Volkova,
• Elena P. Kharitonova and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 481–492, doi:10.3762/bjnano.4.57

• were examined by means of SAXS, thermomechanical analysis (TMA), and were tested in operating fuel cells by means of stationary voltammetry and impedance spectroscopy. The new membranes showed excellent stability in a 2000-hour fuel cell (FC) durability test. The modification of the PBI-O-PhT films

• reduced conductivity due to an excessively high degree of crosslinking. Keywords: composite; high temperature polymer-electrolyte fuel cells (HT-PEFC); impedance spectroscopy; polybenzimidazole (PBI); zirconium; Introduction Polymer-electrolyte fuel cells (PEFC) based on polybenzimidazole (PBI

• the membranes is also confirmed by the double-layer capacitance data presented in Figure 12. The capacitance values, which can be measured by means of impedance spectroscopy, depend on the boundary area between the proton- (PA) and electron- (Pt and carbon support) conducting phases and serve as a

Zeolites as nanoporous, gas-sensitive materials for in situ monitoring of DeNO_x-SCR

• Thomas Simons and
• Ulrich Simon

Beilstein J. Nanotechnol. 2012, 3, 667–673, doi:10.3762/bjnano.3.76

• sensor at the same time. By means of temperature-dependent impedance spectroscopy we found that the thermally induced NH3 desorption in H-form and in Fe-loaded zeolite H-ZSM-5 follow the same process, while a remarkable difference under DeNOx-SCR reaction conditions was found. The Fe-loaded catalyst

• elementary catalytic process promoting a full description of the NH3-SCR reaction system. Keywords: DeNOx-SCR; gas sensing; in situ; impedance spectroscopy; zeolite; Introduction Zeolites are crystalline, nanoporous aluminosilicates composed of [TO4] tetrahedra (T = Si, Al). In H-form zeolites protons

• also applied in gas sensors [12][13][14][15][16][17]. They are proton conductors due to the mobility of the charge-compensating protons. By means of impedance spectroscopy (IS) [18][19][20][21] and quantum chemical calculations on H-ZSM-5 [22][23], we showed in previous works that protons can move

A facile approach to nanoarchitectured three-dimensional graphene-based Li–Mn–O composite as high-power cathodes for Li-ion batteries

• Wenyu Zhang,
• Yi Zeng,
• Chen Xu,
• Ni Xiao,
• Yiben Gao,
• Lain-Jong Li,
• Xiaodong Chen,
• Huey Hoon Hng and
• Qingyu Yan

Beilstein J. Nanotechnol. 2012, 3, 513–523, doi:10.3762/bjnano.3.59

• hybrid sample helps to reduce the dissolution of Mn into the electrolyte further. The superior electrochemical performance of LMO/G electrodes is ascribed to three aspects. First, the LMO/G exhibits fast kinetics of Li-ion and electron diffusion, as examined by the electrochemical impedance spectroscopy

Reduced electron recombination of dye-sensitized solar cells based on TiO₂ spheres consisting of ultrathin nanosheets with [001] facet exposed

• Hongxia Wang,
• Meinan Liu,
• Cheng Yan and
• John Bell

Beilstein J. Nanotechnol. 2012, 3, 378–387, doi:10.3762/bjnano.3.44

• consisting of ultrathin nanosheets with 100% of the [001] facet exposed was employed to fabricate dye-sensitized solar cells (DSCs). Investigation of the electron transport and back reaction of the DSCs by electrochemical impedance spectroscopy showed that the spheres had a threefold lower electron

• also observed after TiCl4 treatment. The synergistic effect of the variation of the TiO2 conduction band and the electron recombination determined the open-circuit voltage of the DSC. Keywords: dye-sensitized solar cells; electrochemical impedance spectroscopy; electron recombination; TiO2 [001] facet

• transport and back reaction of the DSCs with the spheres were investigated by electrochemical impedance spectroscopy. In addition, the effect of treatment by an aqueous solution of TiCl4 on the performance of the DSCs with the TiO2 spheres was discussed. Experimental Synthesis of TiO2 nanosheet particles

Schottky junction/ohmic contact behavior of a nanoporous TiO₂ thin film photoanode in contact with redox electrolyte solutions

• Masao Kaneko,
• Hirohito Ueno and
• Junichi Nemoto

Beilstein J. Nanotechnol. 2011, 2, 127–134, doi:10.3762/bjnano.2.15

• are low for such mesoporous TiO2 thin film as investigated by an alternating current impedance spectroscopy. The electron conductivity of TiO2 itself is not high. However, the carrier density N of 6.96 × 1019 cm−3 obtained from Figure 4 was high, in the order as that of graphite, indicating that the

Microfluidic anodization of aluminum films for the fabrication of nanoporous lipid bilayer support structures

• Jaydeep Bhattacharya,
• Alexandre Kisner,
• Andreas Offenhäusser and
• Bernhard Wolfrum

Beilstein J. Nanotechnol. 2011, 2, 104–109, doi:10.3762/bjnano.2.12

• monitored by impedance spectroscopy across the nanoporous alumina membrane in real-time. Our approach offers a simple and efficient methodology to investigate the activity of transmembrane proteins or ion diffusion across membrane bilayers. Keywords: anodization; lipid bilayer; microfluidics

• formation of lipid bilayers on top of the nanoporous membrane which is monitored using impedance spectroscopy. Experimental The experimental setup for the microfluidic anodization approach is shown schematically in Figure 1. The aluminum substrate, either a 30 µm thick aluminum foil or a thin aluminum film

• the nanoporous membrane. The dissolution of the barrier layer was monitored via impedance spectroscopy (10 Hz to 10 kHz) across the nanoporous alumina membrane by a modular electrochemical system [Autolab (PGSTAT 100/FRA2), Eco Chemie Utrecht, The Netherlands] using silver/silver chloride electrodes