Atomic-level characterization and cilostazol affinity of poly(lactic acid) nanoparticles conjugated with differentially charged hydrophilic molecules

• María Francisca Matus,
• Martín Ludueña,
• Cristian Vilos,
• Iván Palomo and
• Marcelo M. Mariscal

Beilstein J. Nanotechnol. 2018, 9, 1328–1338, doi:10.3762/bjnano.9.126

• , such as core–lipid interface (cyan dotted line), polar zone (purple dotted line) and surface charge (orange dotted line). The distance between the center of mass and the boundary areas is represented using the same color as the dotted lines. Snapshots of initial (left) and final (right) conformation of

Surface characterization of nanoparticles using near-field light scattering

• Eunsoo Yoo,
• Yizhong Liu,
• Chukwuazam A. Nwasike,
• Sebastian R. Freeman,
• Brian C. DiPaolo,
• Bernardo Cordovez and
• Amber L. Doiron

Beilstein J. Nanotechnol. 2018, 9, 1228–1238, doi:10.3762/bjnano.9.114

• the attraction between the nanoparticle and waveguide. Researchers attributed the increased diffusion of PEGylated particles towards the waveguide to the slight reduction in particle surface charge (zeta potential) after PEGylation [24]. This study provided evidence that the nanophotonic force

Electrostatic force spectroscopy revealing the degree of reduction of individual graphene oxide sheets

• Yue Shen,
• Ying Wang,
• Yuan Zhou,
• Chunxi Hai,
• Jun Hu and
• Yi Zhang

Beilstein J. Nanotechnol. 2018, 9, 1146–1155, doi:10.3762/bjnano.9.106

• substrate. The apparent height (polarization height) of nanomaterials in SPFM images are an indication of the local dielectric constant difference between the sample and substrate [20][37]. However, when a DC bias is applied, a local net charge (or the surface charge for nanomaterials) would affect the

Engineering of oriented carbon nanotubes in composite materials

• Razieh Beigmoradi,
• Abdolreza Samimi and
• Davod Mohebbi-Kalhori

Beilstein J. Nanotechnol. 2018, 9, 415–435, doi:10.3762/bjnano.9.41

• spectroscopy: The XPS technique does not explore the whole sample volume but rather provides information about the chemical composition of the CNT surface [144][145]. XPS suffers from surface charge artifacts, so correct sample preparation is crucial to achieve a flat and uncontaminated surface. Despite the

The nanofluidic confinement apparatus: studying confinement-dependent nanoparticle behavior and diffusion

• Stefan Fringes,
• Felix Holzner and
• Armin W. Knoll

Beilstein J. Nanotechnol. 2018, 9, 301–310, doi:10.3762/bjnano.9.30

• diffusion. We note, however, that the same effect could be induced by a charge modulation of the surface potential (or correspondingly the surface charge) by ≈5%. To further investigate the origin of the obstacles we analyzed the time-averaged lateral particle distribution and its correlation to the

• , because pronounced subdiffusion is only observed for gap distances of d < 120 nm. In bulk, the electroviscous effect is attributed to the surface charge of the particles and leads to an increased effective viscosity and thus to a reduction in particle diffusion [37]. A similar mechanism should also play a

CdSe nanorod/TiO₂ nanoparticle heterojunctions with enhanced solar- and visible-light photocatalytic activity

• Fakher Laatar,
• Hatem Moussa,
• Halima Alem,
• Lavinia Balan,
• Emilien Girot,
• Ghouti Medjahdi,
• Hatem Ezzaouia and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2017, 8, 2741–2752, doi:10.3762/bjnano.8.273

• produced. Influence of the pH of the rhodamine B solution The pH of the aqueous solution may play a crucial role on the kinetic of the photodegradation since it influences the surface charge of the catalyst and the structure of the dye in solution. Figure 8 shows that the CdSe (2 wt %)/TiO2 photocatalyst

Enhanced photoelectrochemical water splitting performance using morphology-controlled BiVO₄ with W doping

• Xin Zhao and
• Zhong Chen

Beilstein J. Nanotechnol. 2017, 8, 2640–2647, doi:10.3762/bjnano.8.264

• the surface charge injection (inset in Figure 6b) [25]. In the equivalent circuit, Rs represents the sum of resistance values of the FTO film, the external electrical contacts, and the liquid electrolyte; Rct and Cbulk represent, respectively, the direct charge transfer resistance, and a capacitance

• more surface depletion layers, which leads to a higher capacitance. The surface charge transfer resistance of the sample 0-water is about 3783 Ω, while the one of sample 1-EG is smaller at around 2629 Ω. The smaller charge transfer resistance leads to a higher interfacial charge injection efficiency

• for water oxidation as shown in Figure 5c. It was reported that a porous film with a larger surface area has led to a lower interfacial charge transfer efficiency for water oxidation than its dense counterpart [12]. The current work indicates an opposite trend in that the surface charge injection was

The role of ligands in coinage-metal nanoparticles for electronics

• Ioannis Kanelidis and
• Tobias Kraus

Beilstein J. Nanotechnol. 2017, 8, 2625–2639, doi:10.3762/bjnano.8.263

• transferred to various solid substrates [100]. In a similar study, the exchange of citrate ligands by thioglycolic acid (Figure 2) allowed the authors to reduce the surface charge density, manipulate Coulomb repulsion between the particles, and initiate agglomeration in solution. Appropriate particle charges

Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals

• Somi Kang,
• Sean E. Lehman,
• Matthew V. Schulmerich,
• An-Phong Le,
• Tae-woo Lee,
• Stephen K. Gray,
• Rohit Bhargava and
• Ralph G. Nuzzo

Beilstein J. Nanotechnol. 2017, 8, 2492–2503, doi:10.3762/bjnano.8.249

• interparticle interactions mediated via operando sensitive attributes of surface charge. This intrinsically makes plasmonic crystals more attractive for sensing applications as the need to modify the surface chemistry/charge figures heavily in design of capacities to support the recognition of specific solution

Adsorption of iron tetraphenylporphyrin on (111) surfaces of coinage metals: a density functional theory study

• Hao Tang,
• Nathalie Tarrat,
• Véronique Langlais and
• Yongfeng Wang

Beilstein J. Nanotechnol. 2017, 8, 2484–2491, doi:10.3762/bjnano.8.248

• direct coordination between the Fe and the Au atom, the transfer is slightly larger with 0.29e. The variation of partial charge on Fe (ΔqFe) is a loss of about 0.04e (0.06e for HS on top site). The sign of this variation is the same as the molecule–surface charge transfer. As shown in [16], the Fe centre

Involvement of two uptake mechanisms of gold and iron oxide nanoparticles in a co-exposure scenario using mouse macrophages

• Dimitri Vanhecke,
• Dagmar A. Kuhn,
• Dorleta Jimenez de Aberasturi,
• Sandor Balog,
• Ana Milosevic,
• Dominic Urban,
• Diana Peckys,
• Niels de Jonge,
• Wolfgang J. Parak,
• Alke Petri-Fink and
• Barbara Rothen-Rutishauser

Beilstein J. Nanotechnol. 2017, 8, 2396–2409, doi:10.3762/bjnano.8.239

• cells such as cell type [10][11], surface charge [12][13] and NP size [14][15]. Clathrin- and caveolin-mediated endocytosis are the main uptake mechanisms for PEGylated AuNPs (15 nm) into A549 cells, whereas non PEGylated, citrate-stabilized AuNPs were mainly taken up by micropinocytosis [16

Substrate and Mg doping effects in GaAs nanowires

• Perumal Kannappan,
• Nabiha Ben Sedrine,
• Jennifer P. Teixeira,
• Maria R. Soares,
• Bruno P. Falcão,
• Maria R. Correia,
• Nestor Cifuentes,
• Emilson R. Viana,
• Marcus V. B. Moreira,
• Geraldo M. Ribeiro,
• Alfredo G. de Oliveira,
• Juan C. González and
• Joaquim P. Leitão

Beilstein J. Nanotechnol. 2017, 8, 2126–2138, doi:10.3762/bjnano.8.212

• surface charge traps that induce a pinning of the Fermi level at the surface, especially for diameters below 100 nm [68]. However, if we compare the diameter of the three studied nanowires #1, #2 and #3, which were 190, 187 and 179 nm, respectively, the effect of surface scattering should be similar

A comparative study of the nanoscale and macroscale tribological attributes of alumina and stainless steel surfaces immersed in aqueous suspensions of positively or negatively charged nanodiamonds

• Colin K. Curtis,
• Antonin Marek,
• Alex I. Smirnov and
• Jacqueline Krim

Beilstein J. Nanotechnol. 2017, 8, 2045–2059, doi:10.3762/bjnano.8.205

• the friction coefficient. For example, if a sample was immersed in a ND suspension with an opposite surface charge to its first exposure, µk would shift up or down depending on the sign of the ND charge in the second exposure. The observations suggest that −ND have a strong affinity for the surfaces

• , summarized in Table 1, exhibit a decrease in frequency after the exposure to the suspensions regardless of the ND surface charge sign. While some of the downward shifts in frequency may be attributable to a variation in the uptake of particulate and physisorbed species from air, the net mass increase is

• experimental shifts are attributable to the surface roughness of the electrodes. Changes in f and R for the samples exposed to ND suspensions were found to be dependent on the ND surface charge. Both the alumina and SS304 samples exhibit a slow, yet a small increase in f upon an exposure to +ND suspension

Advances and challenges in the field of plasma polymer nanoparticles

• Andrei Choukourov,
• Pavel Pleskunov,
• Daniil Nikitin,
• Valerii Titov,
• Artem Shelemin,
• Mykhailo Vaidulych,
• Anna Kuzminova,
• Pavel Solař,
• Jan Hanuš,
• Jaroslav Kousal,
• Ondřej Kylián,
• Danka Slavínská and
• Hynek Biederman

Beilstein J. Nanotechnol. 2017, 8, 2002–2014, doi:10.3762/bjnano.8.200

• sources in the production of plasma polymer NPs opens new horizons in precise tuning of their size, shape, chemical composition, surface charge and wettability. There are great potential benefits for the use of plasma polymer NPs in photonics, nanomedicine and other applications, but also significant

Uptake and intracellular accumulation of diamond nanoparticles – a metabolic and cytotoxic study

• Antonín Brož,
• Lucie Bačáková,
• Pavla Štenclová,
• Alexander Kromka and
• Štěpán Potocký

Beilstein J. Nanotechnol. 2017, 8, 1649–1657, doi:10.3762/bjnano.8.165

• ][27], particle size reduction [22] and surface oxidation (i.e., the surface is covered by defined starting functional groups). The cytotoxicity of NDs depends on their origin (i.e., DNDs or HPHT NDs), their size (distribution), their tendency to form aggregates (surface charge), the presence of

• their zeta potential, which influences the aggregation or the selection of adhered proteins from the culture medium. The as-received DNDs have a strongly positive zeta potential of ≈40 mV, while oxidation reverses it to approximately −40 mV [41]. The cell surface charge is influenced by the actual

• biochemical composition of the cytoplasmic membrane and the state of the cell. It is an important biophysical parameter influencing the interaction with the cell surroundings. The cell surface charge (zeta potential) of human cells was between −20 and −30 mV caused by the presence of nonionogenic groups

The effect of the electrical double layer on hydrodynamic lubrication: a non-monotonic trend with increasing zeta potential

• Dalei Jing,
• Yunlu Pan and
• Xiaoming Wang

Beilstein J. Nanotechnol. 2017, 8, 1515–1522, doi:10.3762/bjnano.8.152

• of charged frictional pair–lubricant interface and the resulting electrical double layer (EDL) within the lubricant have been recognized and studied [5][6][7][8][9][10][11][12][13]. The generation of surface charge at the frictional pair–lubricant interface is wide, especially for the frictional

• lubrication theory have a history dating back to hundreds of years, the role of surface-charge-induced EDL on the lubrication is a relatively new field. This role was first considered for the study of thin film lubrication by Bike and Prieve [6]. Following them, Zhang and Umehara [7] introduced the effect of

• the EDL on modifying the conventional Reynolds equation, analyzing the hydrodynamic lubrication. They found that the minimum lubricant film thickness increased with the increasing absolute value of zeta potential (an important parameter of EDL to manifest the surface charge at the solid–liquid

Development of polycationic amphiphilic cyclodextrin nanoparticles for anticancer drug delivery

• Gamze Varan,
• Juan M. Benito,
• Carmen Ortiz Mellet and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1457–1468, doi:10.3762/bjnano.8.145

• derivatives provide suitable nanometer-sized drug delivery systems for safe and efficient intravenous paclitaxel delivery for chemotherapy. In the light of these studies, it can be said that amphiphilic cyclodextrin nanoparticles of different surface charge can be considered as a promising alternative for

• several factors that influence the particle size, particle distribution, surface charge, homogeneity and shape of nanometer-sized drug delivery systems. These factors have a subsequent influence on the biodistribution and the fate of the nanomedicine in the body [27]. In this case, the formulation

• of the polymer/polysaccharide used to prepare the nanoparticles. Therefore, in order to determine the effect of surface charge on drug loading capacity of nanoparticles, PCX was chosen as a model anticancer drug frequently used in chemotherapy for patients with breast cancer. The encapsulation

Cationic PEGylated polycaprolactone nanoparticles carrying post-operation docetaxel for glioma treatment

• Cem Varan and
• Erem Bilensoy

Beilstein J. Nanotechnol. 2017, 8, 1446–1456, doi:10.3762/bjnano.8.144

• than 100 nm and a net positive surface charge to facilitate cellular internalization of drug-loaded nanoparticles. Hydroxypropyl cellulose films were prepared to incorporate these nanoparticle dispersions to complete the implantable drug delivery system. Results: The diameter of core–shell

• nanoparticles were in the range of 70–270 nm, depending on the preparation technique, polymer type and coating. Moreover, the chitosan coating significantly altered the surface charge of the nanoparticles to net positive values of +30 to +50 mV. The model drug docetaxel was successfully loaded into all

• particles (which have neutral or near-neutral surface charge) are more prone to escape from the MPS. Cationic nanoparticles can also condense nucleic acid (DNA, RNA) or proteins to form polyplexes for intracellular gene/drug delivery. In this context, chitosan (CS) is used as a positively charged coating

Evaluation of quantum dot conjugated antibodies for immunofluorescent labelling of cellular targets

• Jennifer E. Francis,
• David Mason and
• Raphaël Lévy

Beilstein J. Nanotechnol. 2017, 8, 1238–1249, doi:10.3762/bjnano.8.125

• between Qdots and functional antibodies, the overall surface charge of Qdot-Ab conjugates, and whether there is a presence of a protein corona. The labelling ratio of Qdots to antibodies present within commercially available Qdot-Ab conjugates has been previously evaluated, where the non-specific

• orientation in which the IgG molecules bind to Qdots cannot be controlled [37]. The binding affinity of Qdot-Abs can also be affected by the surface charge they possess. For instance, positively charged Qdots are taken up by cells more readily than negatively charged or zwitterionic Qdots, which suppress

Needs and challenges for assessing the environmental impacts of engineered nanomaterials (ENMs)

• Michelle Romero-Franco,
• Hilary A. Godwin,
• Muhammad Bilal and
• Yoram Cohen

Beilstein J. Nanotechnol. 2017, 8, 989–1014, doi:10.3762/bjnano.8.101

• composition, surface coating, molecular structure, crystal structure, physical, form/shape, particle size, size distribution and surface area, agglomeration state, particle density, ENM bulk density, porosity, dispersibility, solubility in water and biologically relevant fluids, surface charge, and surface

Scaling law to determine peak forces in tapping-mode AFM experiments on finite elastic soft matter systems

• Horacio V. Guzman

Beilstein J. Nanotechnol. 2017, 8, 968–974, doi:10.3762/bjnano.8.98

• has been deduced. Such deduction has been based in the previous works by the author [15]. The fact of reducing the electrostatic interactions of the surface charge depends strongly on the ionic strength and pH values of the liquid [32]. Thus, immersing the surface sample and the probe into a liquid

Near-field surface plasmon field enhancement induced by rippled surfaces

• Mario D’Acunto,
• Francesco Fuso,
• Ruggero Micheletto,
• Makoto Naruse,
• Francesco Tantussi and
• Maria Allegrini

Beilstein J. Nanotechnol. 2017, 8, 956–967, doi:10.3762/bjnano.8.97

• . Our approach follows the so-called surface integral equations (SIEs) [34][35] approach. Initially, we implemented the SIEs based on the boundary element method (BEM), where ad-hoc integral equations for the surface charge and current density must be considered [36]. A second approach was based on a

• represented in Figure 4. Another critical factor that affects the localized hot spots is the polarization [13]. Since the plasmon resonance depends on the restoring force resulting from a noncompensated surface charge, this force depends ultimately on the shape of the topography profile and polarization, i.e

α-((4-Cyanobenzoyl)oxy)-ω-methyl poly(ethylene glycol): a new stabilizer for silver nanoparticles

• Jana Lutze,
• Miguel A. Bañares,
• Marcos Pita,
• Andrea Haase,
• Andreas Luch and
• Andreas Taubert

Beilstein J. Nanotechnol. 2017, 8, 627–635, doi:10.3762/bjnano.8.67

• produces a negatively charged carboxylate (from 4-cyanobenzoic acid attached to the SNP surface) and a neutral alcohol (from the free PEG chains released from the surface). The –OH group does not affect the surface charge at pH 12 but the higher number of negative charges from the cleaved benzoic acid

Gas sensing properties of MWCNT layers electrochemically decorated with Au and Pd nanoparticles

• Elena Dilonardo,
• Michele Penza,
• Marco Alvisi,
• Riccardo Rossi,
• Gennaro Cassano,
• Cinzia Di Franco,
• Francesco Palmisano,
• Luisa Torsi and
• Nicola Cioffi

Beilstein J. Nanotechnol. 2017, 8, 592–603, doi:10.3762/bjnano.8.64

• 12 ± 2 nm and 5.0 ± 0.5 nm, respectively, as reported in the TEM images in Figure 1. The net positive surface charge of colloidal metal NPs, given by the quaternary ammonium surfactant [36][37], was used to functionalize the surface of the MWCNTs by electrophoresis. The lipophilic interactions

Template-controlled piezoactivity of ZnO thin films grown via a bioinspired approach

• Nina J. Blumenstein,
• Fabian Streb,
• Stefan Walheim,
• Thomas Schimmel,
• Zaklina Burghard and
• Joachim Bill

Beilstein J. Nanotechnol. 2017, 8, 296–303, doi:10.3762/bjnano.8.32

• indicates that the sulfonate functionality leads to a highly polar surface of the template, whereas the carboxylate is less negatively charged. However, it has to be taken into account that the deposition experiments take place in methanol. The solvent influences the effective surface charge of the

• ions as can be seen from the pKa values reported by Rived et al. [43]. Therefore, it is probable that the surface charge of the used templates is lower in methanol than it could be expected from zeta potential measurements in water. Nevertheless, the polarity of the two templates is high enough to

• templates. The negative surface charge of the sulfonate-functional groups of the PEL (−115 mV [40]) is high enough to homogeneously attract the dipolar ZnO particles from solution. The result is a closed film even at low numbers of deposition cycles. In contrast, the negative charge density of the