Effects of substrate stiffness on the viscoelasticity and migration of prostate cancer cells examined by atomic force microscopy

• Xiaoqiong Tang,
• Yan Zhang,
• Jiangbing Mao,
• Yuhua Wang,
• Zhenghong Zhang,
• Zhengchao Wang and
• Hongqin Yang

Beilstein J. Nanotechnol. 2022, 13, 560–569, doi:10.3762/bjnano.13.47

• Germany) for 2 h to prevent damage to the cells. Before the experiment, the thermal noise method was used to adjust the cantilever spring constant, and then the experiment was carried out in contact mode. The AFM probe (MLCT probe, Bruker, USA) slightly contacted the cell surface and a constant force was

Design and characterization of polymeric microneedles containing extracts of Brazilian green propolis

• Camila Felix Vecchi,
• Rafaela Said dos Santos,
• Jéssica Bassi da Silva and
• Marcos Luciano Bruschi

Beilstein J. Nanotechnol. 2022, 13, 503–516, doi:10.3762/bjnano.13.42

• permeation mechanism [6][9][10]. Nanocarriers can be used together with polymeric MNs in a synergistic therapy. The nanocarriers can immediately come into contact with the stratum corneum with the help of polymeric MNs, enhancing the transdermal drug delivery of the drugs. Furthermore, these polymeric MNs

• epidermis and, after a period, the MN system is removed [6]. Dissolvable MNs are composed of a biodegradable matrix containing the bioactive agent. When they come in contact with aqueous fluids in the skin, these needles dissolve, releasing the drug and degrading. As they are dissolvable, they do not need

Ethosomal (−)-epigallocatechin-3-gallate as a novel approach to enhance antioxidant, anti-collagenase and anti-elastase effects

• Çiğdem Yücel,
• Gökçe Şeker Karatoprak,
• Sena Yalçıntaş and
• Tuğba Eren Böncü

Beilstein J. Nanotechnol. 2022, 13, 491–502, doi:10.3762/bjnano.13.41

• dermal sites for the study of antiaging effects. These formulations can also serve as a useful tool to prolong the contact time of EGCG with the skin. Thus, new opportunities may be created for well-controlled and modern topical application of EGCG in cosmetology. Experimental Materials

Zinc oxide nanostructures for fluorescence and Raman signal enhancement: a review

• Ioana Marica,
• Fran Nekvapil,
• Maria Ștefan,
• Cosmin Farcău and
• Alexandra Falamaș

Beilstein J. Nanotechnol. 2022, 13, 472–490, doi:10.3762/bjnano.13.40

• contact with Ag (WAg = 4.36 eV) and Au (WAu = 5.1 eV), whereby charge transfer occurs in the direction ZnO–Ag or Au. Furthermore, the PATP spacer between ZnO and Ag acts to inhibit the charge transfer. The study conducted by Zhou et al. [67] revealed the Raman signal of dopamine using Au–ZnO heterogeneous

• in Figure 7A based on the description in [101]. First, the ZnO is excited and because most of the electrons are trapped in the defect level of ZnO NRs, they will recombine with the holes in the VB resulting in a visible-range emission. In the case of contact between ZnO NRs and Au NPs, the Au NPs can

• of molecules in contact with nanostructured ZnO substrates. For example, [117] concluded that the surface area of ZnO or protein coverage does not influence the fluorescence enhancement, but is related to the intrinsic properties of ZnO. They also noted that the enhanced fluorescence could be

Tubular glassy carbon microneedles with fullerene-like tips for biomedical applications

• Sharali Malik and
• George E. Kostakis

Beilstein J. Nanotechnol. 2022, 13, 455–461, doi:10.3762/bjnano.13.38

• chrome particles released from surgical stainless steel needles during needle wear in human skin. Allergic reactions such as contact dermatitis resulting from the presence of nickel and chromium in acupuncture needles have also been reported [32]. Glassy carbon is biocompatible, electrically and

The role of sulfonate groups and hydrogen bonding in the proton conductivity of two coordination networks

• Ali Javed,
• Felix Steinke,
• Stephan Wöhlbrandt,
• Hana Bunzen,
• Norbert Stock and
• Michael Tiemann

Beilstein J. Nanotechnol. 2022, 13, 437–443, doi:10.3762/bjnano.13.36

• necessary, as will be discussed below. The proton conductivity σ is then calculated from the resistance R by accounting for the thickness L and contact area A of the sample pellet between the two electrodes (σ = R−1·L·A−1) [21]. The results are shown in Table 1. Further conductivity values at 22 °C are

A non-enzymatic electrochemical hydrogen peroxide sensor based on copper oxide nanostructures

• Irena Mihailova,
• Vjaceslavs Gerbreders,
• Marina Krasovska,
• Eriks Sledevskis,
• Valdis Mizers,
• Andrejs Bulanovs and
• Andrejs Ogurcovs

Beilstein J. Nanotechnol. 2022, 13, 424–436, doi:10.3762/bjnano.13.35

• mm length to provide electrical contact with the equipment. The measurements were carried out using an electrochemical station (Zanher, Germany), supplemented by a custom-made electrochemical cell (for more details about its structure, see our publication [71]). During the measurement, a three

Electrostatic pull-in application in flexible devices: A review

• Teng Cai,
• Yuming Fang,
• Yingli Fang,
• Ruozhou Li,
• Ying Yu and
• Mingyang Huang

Beilstein J. Nanotechnol. 2022, 13, 390–403, doi:10.3762/bjnano.13.32

• plate are balanced. As the voltage continues to increase, the upper plate moves rapidly downward and the two plates eventually contact, known as pull-in. The critical voltage [11] that leads to the pull-in phenomenon is: where k is the elastic modulus of the flexible material, g is the initial distance

• contact electrodes [25][26], or intermediate layer [27], and can greatly improve the life cycles of switches. However, CNTs prepared by CVD are randomly oriented, and positioning CNTs at the desired location is a challenge that hinders scalable manufacturing. Ward et al. [28] and Cha et al. [21] used spin

• tear of the switches, especially for CNT [16] and GR [29] switches. Permanent adhesion caused by the dielectric charging [52][53] and chemical bonding [24] are the focus of the research on improving the life cycles. At present, it is mainly solved by reducing the electrode contact area [14] or

Micro- and nanotechnology in biomedical engineering for cartilage tissue regeneration in osteoarthritis

• Zahra Nabizadeh,
• Mahmoud Nasrollahzadeh,
• Hamed Daemi,
• Mohamadreza Baghaban Eslaminejad,
• Ali Akbar Shabani,
• Mehdi Dadashpour,
• Majid Mirmohammadkhani and
• Davood Nasrabadi

Beilstein J. Nanotechnol. 2022, 13, 363–389, doi:10.3762/bjnano.13.31

The effect of metal surface nanomorphology on the output performance of a TENG

• Yiru Wang,
• Xin Zhao,
• Yang Liu and
• Wenjun Zhou

Beilstein J. Nanotechnol. 2022, 13, 298–312, doi:10.3762/bjnano.13.25

• surface. When the materials are separated, the positive and negative electrostatic charges on the materials will also be separated, resulting in a potential difference. The charge transfer strongly depends on the work functions of the two materials in contact, for example, metal–metal, semiconductor

• –semiconductor and semiconductor–metal contact pairs [14][15]. A semiconductor–metal contact can be described by the band diagram shown in Figure 1. The frictional electrical properties of materials depend on their work functions and Fermi levels [16][17]. The intermediate state in the bandgap can reduce the

• ], many attempts have been made to enhance the energy harvesting efficiency. There are four ways to enhance the efficiency of energy collection. These are (1) surface treatment of the contact materials, including increasing the surface roughness and physical surface modification to enhance the surface

Plasma modes in capacitively coupled superconducting nanowires

• Alex Latyshev,
• Andrew G. Semenov and
• Andrei D. Zaikin

Beilstein J. Nanotechnol. 2022, 13, 292–297, doi:10.3762/bjnano.13.24

• wires can be treated as independent only provided that they are located far from each other. If, on the contrary, the distance between the wires becomes sufficiently short they develop electromagnetic coupling even though there exists no direct electric contact between them. In this case each

Relationship between corrosion and nanoscale friction on a metallic glass

• Haoran Ma and
• Roland Bennewitz

Beilstein J. Nanotechnol. 2022, 13, 236–244, doi:10.3762/bjnano.13.18

• linear increase of the friction force with the applied load is also observed for the outer layer after immersion in phosphate buffer (Figure 4b). We attribute the increase in friction for the outer layer to the contact area between the outer layer and tip, which grows in parallel to the increased contact

• immersion time due to the development of defects in the surface film [40][41]. The increase in the friction coefficient of the outer layer indicates the growth of the outer layer with increasing immersion time. More material of possibly higher shear strength is in contact with the sliding tip, which

• during deformation [48][49]. No plastic strain occurs in this work, given the much higher yield strength of Zr-based MGs (approx. 1.7 GPa [50]) than that of copper (69–365 MPa [51]). The maximum contact pressure in this work is ca. 0.49 GPa (JKR model), smaller than the yield strength of MGs. As a

Impact of device design on the electronic and optoelectronic properties of integrated Ru-terpyridine complexes

• Max Mennicken,
• Sophia Katharina Peter,
• Corinna Kaulen,
• Ulrich Simon and
• Silvia Karthäuser

Beilstein J. Nanotechnol. 2022, 13, 219–229, doi:10.3762/bjnano.13.16

• overcome for hopping conductance. Furthermore, EA corresponding to ΔEH points to hole conduction through the energetically accessible HOMO of Ru(TP)2-complexes, as also discussed in [31][32]. In practical nanowire devices other contributions such as an additional contact resistance or an activation energy

Engineered titania nanomaterials in advanced clinical applications

• Padmavati Sahare,
• Paulina Govea Alvarez,
• Juan Manual Sanchez Yanez,
• Gabriel Luna-Bárcenas,
• Samik Chakraborty,
• Sujay Paul and
• Miriam Estevez

Beilstein J. Nanotechnol. 2022, 13, 201–218, doi:10.3762/bjnano.13.15

• contact angle, which is reported to be favorable for biomedical applications. Likewise, Gatoo et al. proposed that amorphous titania materials are hydrophilic due to the presence of a higher concentration of hydroxy groups upon their surface and the high polarity of the O–Ti–O bond [23]. The surface

• (GNP2) presented good osseointegration [61]. In another recent study, TiO2 nanotubes (TNT) were grown on the surface of medical-grade titanium alloy and then coated with silver nps (Ag nps) to improve the antimicrobial properties of the implants. Moreover, to avoid direct contact of Ag nps with human

A comprehensive review on electrospun nanohybrid membranes for wastewater treatment

• Senuri Kumarage,
• Imalka Munaweera and
• Nilwala Kottegoda

Beilstein J. Nanotechnol. 2022, 13, 137–159, doi:10.3762/bjnano.13.10

• layer had a significant effect on the hydrophilicity of the membrane by decreasing the water contact angle from 130° to 13°. A water flux of 5.5 m3/m2/day, has been achieved by the membrane with the lowest contact angle [67]. Zhang et al. demonstrated the electrospinning of a blend of PLA and poly(3

• separating nanohybrid membrane with a SiO2 NP-integrated F-PBZ functional layer on the surface of an electrospun core–shell-structured membrane of CA/PI nanofibers. The membrane showed hydrophobicity with a water contact angle of 160° and superlipophilicity with an extremely low oil contact angle of 0°. The

• hydrophobic PVDF membrane to a hydrophilic membrane with a water contact angle of 22.72°. The nanohybrid membrane showed a dye removal efficiency of 88.9% and an adsorption capacity of 72.6 mg/g for IC [78]. Huong et al. developed a waste protein-immobilized cationic dye removal membrane from PAN. In this

Nanoscale friction and wear of a polymer coated with graphene

• Robin Vacher and
• Astrid S. de Wijn

Beilstein J. Nanotechnol. 2022, 13, 63–73, doi:10.3762/bjnano.13.4

• used by Li and co-workers [32]. ε = 0.092 eV is the depth potential, and σ2 = 3 Å is the distance at which the potential is equal to zero. In our system, the tip and polymer are never in direct contact. They are always separated by graphene. We therefore do not need to model their interactions. However

Effect of lubricants on the rotational transmission between solid-state gears

• Huang-Hsiang Lin,
• Jonathan Heinze,
• Alexander Croy,
• Rafael Gutiérrez and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3

• formation process between gears. Keywords: lubricants; MD simulation; rotational transmission; solid-state gears; Introduction In mechanical systems, lubrication is the most common way to reduce friction and wear [1][2][3][4]. The idea of lubricants is preventing direct contact between surfaces to avoid

• problem are carried out with fixed rotational speed for both gears. In this case, the gears will never be in contact with each other and only lubricant properties are calculated accordingly by the dynamical meshing at each time step. Moreover, as the system dimension approaches the nanoscale, the

• ]. To proceed further, one may ask if lubricants can provide the same functionality as in the macroscopic case and are able to improve the transmission efficiency. Consider the case where the lubricant film within the contact area consists only of a small number of molecules. In this case, the pressure

Design aspects of Bi₂Sr₂CaCu₂O_8+δ THz sources: optimization of thermal and radiative properties

• Mikhail M. Krasnov,
• Natalia D. Novikova,
• Roger Cattaneo,
• Alexey A. Kalenyuk and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 1392–1403, doi:10.3762/bjnano.12.103

• in a direct contact with the sapphire substrate (no epoxy). This creates a good thermal sink and, as a result, Tmax falls to ≈23 K. Addition of an exchange gas does not play a major role in this case because the main heat sink channel is provided by the electrode [33][34] acting as a heat spreading

Measurement of polarization effects in dual-phase ceria-based oxygen permeation membranes using Kelvin probe force microscopy

• Kerstin Neuhaus,
• Christina Schmidt,
• Liudmila Fischer,
• Wilhelm Albert Meulenberg,
• Ke Ran,
• Joachim Mayer and
• Stefan Baumann

Beilstein J. Nanotechnol. 2021, 12, 1380–1391, doi:10.3762/bjnano.12.102

• were performed in a single-pass experiment. For this kind of measurements, the surface potential and the sample topography are mapped in a single pass in intermittent contact mode with the cantilever vibrating at its resonance frequency (i.e., the cantilever is not in lift mode during this experiment

• ceria materials led to a more positive surface potential in the direct vicinity of the contact area, while a negative voltage led to a more negative surface potential. The surface potential gradient was also shown to be reversible over time as long as the applied voltage was kept in a certain range. The

• electrochemical studies. The surface potential at the direct contact point of the measuring tip can be determined from the KPFM measurement data at different times after the end of polarization. The results usually follow an exponential rule if plotting ΔΦSP versus time. By fitting of the expontential function

Chemical vapor deposition of germanium-rich CrGe_x nanowires

• Vladislav Dřínek,
• Stanislav Tiagulskyi,
• Roman Yatskiv,
• Jan Grym,
• Radek Fajgar,
• Věra Jandová,
• Martin Koštejn and
• Jaroslav Kupčík

Beilstein J. Nanotechnol. 2021, 12, 1365–1371, doi:10.3762/bjnano.12.100

• transfer single NWs onto contact lithographic pads (Supporting Information File 1, Figure S9) to measure their conductivity. The NWs, however, turned out to be fragile and were destroyed when an attempt was made to cut them from the tungsten tip using a focused ion beam (FIB). Therefore, a method to

• directly contact an as-grown single NW was developed. This method allowed us to measure the conductivity between the molybdenum substrate and the point of contact of the tungsten tip with the NW. To limit the contact resistance between the tungsten tip and the NW, the tip was soldered to the NW with a

• with the Ga+ focused ion beam (FIB), gas injection system (GIS), and nanomanipulator OmniProbe 400 (Oxford Instruments) with a tungsten tip. The nanomanipulator enabled a direct contact of single as-grown NWs. The current–voltage (I–V) characteristics were measured using a Keithley 237 source

Cantilever signature of tip detachment during contact resonance AFM

• Devin Kalafut,
• Ryan Wagner,
• Maria Jose Cadena,
• Anil Bajaj and
• Arvind Raman

Beilstein J. Nanotechnol. 2021, 12, 1286–1296, doi:10.3762/bjnano.12.96

• Devin Kalafut Ryan Wagner Maria Jose Cadena Anil Bajaj Arvind Raman School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA 10.3762/bjnano.12.96 Abstract Contact resonance atomic force microscopy, piezoresponse force microscopy, and electrochemical strain microscopy are

• atomic force microscopy modes in which the cantilever is held in contact with the sample at a constant average force while monitoring the cantilever motion under the influence of a small, superimposed vibrational signal. Though these modes depend on permanent contact, there is a lack of detailed analysis

• connect the qualitative and quantitative behavior to experimental features. Keywords: atomic force microscopy (AFM); contact resonance; nonlinear normal mode (NNM); tip–sample detachment; photothermal excitation; Introduction Contact resonance atomic force microscopy (CR-AFM) [1][2], piezoresponse force

Enhancement of the piezoelectric coefficient in PVDF-TrFe/CoFe₂O₄ nanocomposites through DC magnetic poling

• Marco Fortunato,
• Alessio Tamburrano,
• Maria Paola Bracciale,
• Maria Laura Santarelli and
• Maria Sabrina Sarto

Beilstein J. Nanotechnol. 2021, 12, 1262–1270, doi:10.3762/bjnano.12.93

• temperatures. This process, usually referred to as electrical poling, requires the deposition of contact electrodes on the sample surface and the use of high-voltage apparatus. In the present work, in order to overcome these constraints, we have produced, characterized, and studied a polymer nanocomposite

A review on slip boundary conditions at the nanoscale: recent development and applications

• Ruifei Wang,
• Jin Chai,
• Bobo Luo,
• Xiong Liu,
• Jianting Zhang,
• Min Wu,
• Mingdan Wei and
• Zhuanyue Ma

Beilstein J. Nanotechnol. 2021, 12, 1237–1251, doi:10.3762/bjnano.12.91

• affect the boundary slip, and many previous investigations have shown that, from qualitative points of view, the positive slip length monotonically increases with the increase in the contact angle [57][58][59][60][61]. Furthermore, when studying the water flow on smooth surfaces, there is a

• quasiuniversal relationship between the slip length and the static contact angle as follows (see Equation 3 and Figure 2). It has been shown that Equation 3 can be interpreted on the grounds of definite physical principles, according to the microscopic connection between slip length, contact angle, and the

• liquid–solid interaction parameter [62]. However, it should be noted that this model is only applicable to cases of water slippage on smooth surfaces, and there are some deviations for water slippage on rough surfaces [66]. On the other hand, even on very smooth surfaces, the contact angle, surface–water

Two dynamic modes to streamline challenging atomic force microscopy measurements

• Alexei G. Temiryazev,
• Andrey V. Krayev and
• Marina P. Temiryazeva

Beilstein J. Nanotechnol. 2021, 12, 1226–1236, doi:10.3762/bjnano.12.90

• flexible console with a sharp tip at the end. Two main classes of scanning methods can be distinguished, namely contact and dynamic scanning. During contact scanning, the tip is pressed against the surface and the pressing force is controlled by the deflection of the console. A similar way to control the

• interaction of the probe with the sample is used in off-resonance dynamic modes [6]. Although they have various names, depending on the specific manufacturer (PeakForce Tapping, Hybrid Mode, Digital Pulsed Force Mode), a common feature of these methods is that the transition to the contact is carried out

• periodically with a frequency of 1–2 kHz. In addition to the surface profile, contact methods allow one to obtain some information on the mechanical properties of the material, provided that the contact area between the tip and the sample can be modeled with a reasonable degree of accuracy. In the case of the

The effect of cobalt on morphology, structure, and ORR activity of electrospun carbon fibre mats in aqueous alkaline environments

• Markus Gehring,
• Tobias Kutsch,
• Osmane Camara,
• Alexandre Merlen,
• Hermann Tempel,
• Hans Kungl and
• Rüdiger-A. Eichel

Beilstein J. Nanotechnol. 2021, 12, 1173–1186, doi:10.3762/bjnano.12.87

• active sites, that is, triple-phase contact points. These contact points of air, solid catalyst, and liquid electrolyte, need to be high in number or area. This entails a partial wetting of the electrode to ensure accessibility of the sites for gaseous oxygen. From a more industrial perspective

• carbonised at 800 °C, is decreased when the sample is carbonised at 1000 °C. Cobalt is known to instantaneously oxidise upon contact with air even at room temperature forming an oxide layer with a thickness of 0.8 to 1 nm [28]. Considering the low thickness of the layer and the fact that spontaneous

• particle surface is completely reduced and only re-oxidised upon contact with air. From an application point of view, this oxide/hydroxide layer may even prove beneficial, as both cobalt [16] and its oxides [29] have been shown to enhance the ORR in alkaline media. Carbon matrix structure The XRD