Optimizing PMMA solutions to suppress contamination in the transfer of CVD graphene for batch production

• Chun-Da Liao,
• Andrea Capasso,
• Tiago Queirós,
• Telma Domingues,
• Fatima Cerqueira,
• Nicoleta Nicoara,
• Jérôme Borme,
• Paulo Freitas and
• Pedro Alpuim

Beilstein J. Nanotechnol. 2022, 13, 796–806, doi:10.3762/bjnano.13.70

• , Model: Alpha300M+) with an excitation laser wavelength of 532 nm. A laser power of ca. 2 mW was used for all measurements. The backscattered laser light containing the Raman bands from 1200 to 3000 cm−1 was collected by a CCD camera (Andor, Model number: DV401A-BV-352) integrated with the WITec system

• . The characteristic Raman signature collected from a p-doped Si wafer at 520.7 cm−1 was employed as standard calibration. Raman mapping was conducted by raster scan, where the step size of the laser spot moving over a selected area is 1 µm, and the exposure time of 0.4 s was taken at each point of the

• frequency. The AFM measurement was carried out in tapping mode. A 633 nm laser light aimed at the back side of the cantilever tip was reflected toward a position-sensitive photodetector, which provides feedback signals to piezoelectric scanners that maintain the cantilever tip at constant height (force

Efficient liquid exfoliation of KP₁₅ nanowires aided by Hansen's empirical theory

• Zhaoxuan Huang,
• Zhikang Jiang,
• Nan Tian,
• Disheng Yao,
• Fei Long,
• Yanhan Yang and
• Danmin Liu

Beilstein J. Nanotechnol. 2022, 13, 788–795, doi:10.3762/bjnano.13.69

• . For the Raman tests, KP15 samples were spun on SiO2(300 nm)/Si substrates. The excitation wavelength used was 532 nm, the spot size was approx. 1 μm, and the laser power was kept below 20 μW. For low-temperature Raman measurements, a Linkam THMS600 cryostat cooled by liquid nitrogen was used to

Hierarchical Bi₂WO₆/TiO₂-nanotube composites derived from natural cellulose for visible-light photocatalytic treatment of pollutants

• Zehao Lin,
• Zhan Yang and
• Jianguo Huang

Beilstein J. Nanotechnol. 2022, 13, 745–762, doi:10.3762/bjnano.13.66

• reference standard for solid samples. The photoluminescence (PL) spectra were obtained on a Shimadzu RF-5301PC fluorescence spectrometer under a laser excitation of 360 nm. In order to observe the microstructures of the samples, a small amount of a given sample was dispersed in ethanol to generate a

A nonenzymatic reduced graphene oxide-based nanosensor for parathion

• Sarani Sen,
• Anurag Roy,
• Ambarish Sanyal and
• Parukuttyamma Sujatha Devi

Beilstein J. Nanotechnol. 2022, 13, 730–744, doi:10.3762/bjnano.13.65

• spectra of the samples were recorded in the 1000–3500 cm−1 region with a resolution of 1 cm−1 using a Renishaw via a Reflex micro-Raman spectrometer with an argon ion (514.6 nm) laser. The X-ray photoemission spectroscopy (XPS) data were obtained from a PHI 5000 Versa probe II scanning XPS microprobe

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• darkness and illumination degrades the spatial and energy resolutions, reducing the accuracy of SPV measurements on the nanometer scale [23]. To overcome the above problem, direct SPV measurements by means of laser power modulation and a lock-in technique have been proposed. Streicher et al. used two

• force Fele in darkness is described as where ∂C/∂z is the capacitance gradient of the tip–sample system and VCPD is the CPD in darkness. Applying a modulated laser power with a sinusoidal waveform of frequency ωm, which is synchronized with the AC bias (Figure 1b), induces the SPV with the peak-to-peak

• amplitude VSPV: Therefore, the electrostatic force under modulated laser irradiation is described as This equation can be divided into three parts: (Equation 5) is measured to determine the SPV by controlling VAC and nullifying the modulated force where the SPV is derived as Thus, AC-KPFM controls the AC

Nanoarchitectonics of the cathode to improve the reversibility of Li–O₂ batteries

• Hien Thi Thu Pham,
• Jonghyeok Yun,
• So Yeun Kim,
• Sang A Han,
• Jung Ho Kim,
• Jong-Won Lee and
• Min-Sik Park

Beilstein J. Nanotechnol. 2022, 13, 689–698, doi:10.3762/bjnano.13.61

• microstructures of the materials. Powder XRD (PANalytical, Empyrean) and Raman spectroscopy (inVia Raman microscopes, Ar ion laser, 514 nm) were employed to analyze the structures. Their surface chemistry was investigated by XPS (Thermo Scientific, Sigma Probe), while their surface area and porosity were

Fabrication and testing of polymer microneedles for transdermal drug delivery

• Vahid Ebrahiminejad,
• Zahra Faraji Rad,
• Philip D. Prewett and
• Graham J. Davies

Beilstein J. Nanotechnol. 2022, 13, 629–640, doi:10.3762/bjnano.13.55

• multistage fabrication processes with high production costs [7]. Similarly, laser ablation and lithography techniques are costly, requiring extended production time [8]. To overcome the current manufacturing limitations, MNs might be fabricated cost-effectively, with high precision and accuracy, using 3D

• adjust settings such as slicing, shell and scaffolding, laser power, and scanning speeds before converting to General Writing Language (GWL) codes. Parameters such as slicing distance of 2 µm, multiple base slide counts of 4 layers, shell and scaffolding filling method, null shear angle (0°), and laser

• photoresist was drop cast onto an indium tin oxide (ITO) glass substrate prior to starting the printing process. A dip-in laser lithography (DiLL) objective (25× magnification, NA = 0.8) was used for printing, after which the MN array was washed in propylene glycol methyl ether acetate (PGMEA) for 10 minutes

A new method for obtaining the magnetic shape anisotropy directly from electron tomography images

• Cristian Radu,
• Ioana D. Vlaicu and
• Andrei C. Kuncser

Beilstein J. Nanotechnol. 2022, 13, 590–598, doi:10.3762/bjnano.13.51

• , X-ray diffraction, magnetometry [4], transmission/scanning electron imaging [5][6], small-angle scattering techniques [7], dynamic light scattering, laser diffraction [8][9], resonant mass measurement, and spatial filter velocimetry. Each of these has certain features (i.e., ease of access, ease of

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• molybdenum diselenide (MoSe2) flake as surface-enhanced Raman spectroscopy (SERS) platform, we demonstrate the dependency of the Raman enhancement on laser beam polarization and local structure using copper phthalocyanine (CuPc) as probe. Second harmonic generation (SHG) and photoluminescence spectroscopy

• pulsed laser as the excitation source. The real size of the MoSe2 flake is indicated by the dashed white triangle. We find that the SHG signal is barely visible at the border of the MoSe2 flake compared to the center of the MoSe2 flake. Furthermore, the bright-field optical image reveals also some small

• (called Q-band) from 500 to 800 nm. The absorption peaks situated at 627 and 696 nm are due to the second and the first π–π* transition of the phthalocyanine macrocycle, respectively [30]. Therefore, the Raman measurements for CuPc/MoSe2 are conducted using a 636 nm laser, which shows good resonance with

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

• unclear how mechanical properties regulate the cellular response to the environmental matrix. In this study, atomic force microscopy (AFM) and laser confocal imaging were used to qualitatively evaluate the relationship between substrate stiffness and migration of prostate cancer (PCa) cells. Cells

• the assay buffer was used to rinse the cells three times to remove residual esterase activity. Next, the cells were incubated at 37 °C for 15 min in assay buffer containing calcein-AM (1 μM) and PI (3 μM) and then imaged with a laser confocal microscope. Cell migration and invasion assays To assess

• washed with PBS and fluorescence images were obtained using an inverted optical microscope (Leica, Germany) with 488 laser lines. The obtained images were linearly analysed and pseudo-coloured using the ImageJ analysis software. Blebbistatin treatment assay To inhibit myosin II, cells were incubated with

Detection and imaging of Hg(II) in vivo using glutathione-functionalized gold nanoparticles

• Gufeng Li,
• Shaoqing Li,
• Rui Wang,
• Min Yang,
• Lizhu Zhang,
• Yanli Zhang,
• Wenrong Yang and
• Hongbin Wang

Beilstein J. Nanotechnol. 2022, 13, 549–559, doi:10.3762/bjnano.13.46

• to other non-GNP methods. It must be acknowledged that the detection window of GNPs-GSH-Rh6G2 is very wide (0.025–0.3 mM) but at the cost of a high LOD. GNPs-GSH-Rh6G2 bioimaging in living cells To study bioimaging of GSH-Rh6G2 and GNPs-GSH-Rh6G2 in living cells, confocal laser scanning microscopy

• acquired using an OLYMPUS CKX41 inverted fluorescence microscope (Olympus, Japan)/Leica SP5 laser scanning confocal microscope (Leica, Germany). Cell viability was measured by a PectraMax190 microplate reader (Molecular, USA). HPLC-MS was performed on an Agilent-ABQSTAR Pulsar (Agilent, Germany) with a

• were washed with HEPES buffer three times. Then, 30 μL of Hg2+ solution was added. Residual ions were washed with HEPES buffer before imaging. Confocal laser scanning microscopy with 543 nm excitation was carried out. Cytotoxicity assays Cytotoxicity assays were used to investigate the bio-safety of

Influence of thickness and morphology of MoS₂ on the performance of counter electrodes in dye-sensitized solar cells

• Lam Thuy Thi Mai,
• Hai Viet Le,
• Ngan Kim Thi Nguyen,
• Van La Tran Pham,
• Thu Anh Thi Nguyen,
• Nguyen Thanh Le Huynh and
• Hoang Thai Nguyen

Beilstein J. Nanotechnol. 2022, 13, 528–537, doi:10.3762/bjnano.13.44

• performed on a LabRAM HR 800 Raman Spectrometer (HORIBA Jobin Yvon) with an excitation laser source at 532 nm. The morphology of MoS2 thin films was analyzed by an ultrahigh-resolution field-emission scanning electron microscope (FE-SEM, Hitachi SU-8010, Japan). The electrochemical catalytic activity of the

Ciprofloxacin-loaded dissolving polymeric microneedles as a potential therapeutic for the treatment of S. aureus skin infections

• Sharif Abdelghany,
• Walhan Alshaer,
• Yazan Al Thaher,
• Maram Al Fawares,
• Amal G. Al-Bakri,
• Saja Zuriekat and
• Randa SH. Mansour

Beilstein J. Nanotechnol. 2022, 13, 517–527, doi:10.3762/bjnano.13.43

• Ciprofloxacin hydrochloride, PVA, PVP, acetonitrile, phosphoric acid, triethylamine, and phosphate buffer tablets were purchased from Merck, Germany. Staphylococcus aureus (ATCC-29213) was purchased from ATCC, USA. Poly(dimethylsiloxane) (PDMS) molds, including 196 laser-engineered pyramidal holes measuring 200

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

• ordered hybrid nanostructured substrates, ranging from more expensive and laborious ones, such as pulsed laser deposition or hydrothermal growth, followed by sputtering processes [31] or electron beam lithography to more cost-efficient and simple ones, such as photochemical deposition of metallic NPs or a

• ) [12] was carried out as well. Chou et al. employed a simple and rapid method, namely pulsed laser-induced photolysis to develop Au NPs on the surface of ZnO nanorods fabricated by the sol–gel method (Figure 2c,d) [38]. Various irradiation times were tested, indicating that a short irradiation time was

• photochemical reduction [32], pulsed laser-induced photolysis [38], or controlled decoration with Ag NPs using an electroless plating technique [44]. Photochemical synthesis permits the control of nucleation and growth rate without using organic additives. Xu et al. employed laser irradiation of ZnO nanorods in

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

• Raman spectroscopy (WiTec CRM200, laser excitation at 632.8 nm), scanning electron microscopy (SEM Leo 1530, with a spatial resolution of 1 nm at 20 kV and 3 nm at 1 kV, equipped with an energy-dispersive X-ray analysis system EDX INCA 400 from Oxford Instruments), and X-ray diffraction (STOE STADI-P

A broadband detector based on series YBCO grain boundary Josephson junctions

• Egor I. Glushkov,
• Alexander V. Chiginev,
• Leonid S. Kuzmin and
• Leonid S. Revin

Beilstein J. Nanotechnol. 2022, 13, 325–333, doi:10.3762/bjnano.13.27

• a wide frequency range from tens of gigahertz to several terahertz [13][14], which exceeds the gap limitation of low-Tc detectors. So, in [12] the spectrum of a quantum cascade laser emission has been recovered by an YBaCuO detector at a central frequency around 2.2 THz. However, for some

Coordination-assembled myricetin nanoarchitectonics for sustainably scavenging free radicals

• Xiaoyan Ma,
• Haoning Gong,
• Kenji Ogino,
• Xuehai Yan and
• Ruirui Xing

Beilstein J. Nanotechnol. 2022, 13, 284–291, doi:10.3762/bjnano.13.23

• was used to incubate these cells for 5 min and the fluorescence intensity of the cells was recorded via confocal laser scanning microscopy. Results and Discussion Synthesis and characterization of MZG We chose Zn2+, a typical essential metal, to effectively bond Myr and GSH via coordination

• to effectively protect cells from damage. DCFH-DA was used to probe ROS in cells, which showed no fluorescence signal without ROS, while it turned to highly fluorescent 2′7′-dichlorofluorescein after interacting with ROS in cells. As shown in the confocal laser scanning microscopy (CLSM) images, the

Photothermal ablation of murine melanomas by Fe₃O₄ nanoparticle clusters

• Xue Wang,
• Lili Xuan and
• Ying Pan

Beilstein J. Nanotechnol. 2022, 13, 255–264, doi:10.3762/bjnano.13.20

• synthesized Fe3O4 NPCs was confirmed by the conserved DLS pattern of size distribution after five heating/cooling cycles with a NIR laser (Figure 1e). Altogether, our data confirmed the successful fabrication of superparamagnetic Fe3O4 NPCs that are spherical, uniformly sized and highly absorptive in the NIR

• region, validating their potential use as PTT agents. Photothermal effect of Fe3O4 NPCs To assess their photothermal effect, we measured the increments of temperature at different concentrations of Fe3O4 NPCs during 10 min of irradiation with an 808 nm laser in vitro. In general, the Fe3O4 NPC-induced

• Fe3O4 nanoparticle-containing up-conversion nanoprobes [15]. To check whether HSP70 was involved in Fe3O4 NPC-mediated PTT, we treated A375 cells for 24 h with NPCs at concentrations of 0.125 or 0.25 mg/mL, followed by 808 nm laser irradiation. Naïve cells were incubated with saline and served as normal

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

• -bearing mouse xenograft demonstrated that upon laser irradiation in the NIR-II window (1064 nm), the tumor temperature reached up to 53.4 °C, inducing complete photothermal eradication of tumor tissue. This study proves the high synergistic efficacy of combined SDT and PTT of B-TiO2−x nps for the complete

• are the cell key energy centers and are extremely sensitive to heat shock, they contribute to apoptotic cell death by generating ROS. As a result, by lowering the intensity of laser power and dosage, mitochondria-targeted PDT and PTT would provide better results. In the study of Mou and co-workers, a

• NIR laser irradiation at a far lower power density and low intravenous dosage. Phototoxicity essays of G-TiO2−x on HeLa cells using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) showed 85% cell viability, confirming that G-TiO2−x itself is non-toxic even at higher concentrations

Bacterial safety study of the production process of hemoglobin-based oxygen carriers

• Axel Steffen,
• Yu Xiong,
• Radostina Georgieva,
• Ulrich Kalus and
• Hans Bäumler

Beilstein J. Nanotechnol. 2022, 13, 114–126, doi:10.3762/bjnano.13.8

• CCD method produces nearly uniform, peanut-shaped particles. The size distribution determined by dynamic light scattering (DLS) was 759 ± 25 nm. Confocal laser scanning microscopy (CLSM) images confirmed this size range (Figure 1C). Scanning electron microscopy (SEM) images of particles produced with

Influence of magnetic domain walls on all-optical magnetic toggle switching in a ferrimagnetic GdFe film

• Rahil Hosseinifar,
• Evangelos Golias,
• Ivar Kumberg,
• Quentin Guillet,
• Karl Frischmuth,
• Sangeeta Thakur,
• Mario Fix,
• Manfred Albrecht,
• Florian Kronast and
• Wolfgang Kuch

Beilstein J. Nanotechnol. 2022, 13, 74–81, doi:10.3762/bjnano.13.5

• film with out-of-plane easy axis of magnetization by X-ray magnetic circular dichroism photoelectron emission microscopy. Individual linearly polarized laser pulses of 800 nm wavelength and 100 fs duration above a certain threshold fluence reverse the sample magnetization, independent of the

• magnetization direction, the so-called toggle switching. Local deviations from this deterministic behavior close to magnetic domain walls are studied in detail. Reasons for nondeterministic toggle switching are related to extrinsic effects, caused by pulse-to-pulse variations of the exciting laser system, and

• where the line of constant threshold fluence in the Gaussian footprint of the laser pulse comes close to an already existing domain wall. On the other hand, we identify the presence of laser-induced domain-wall motion in the toggle-switching event as a further cause for local deviations from purely

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

• in the synthesis procedures. The most common physical methods used to generate NPs are high-energy ball milling, laser ablation, electrospraying, inert gas condensation, PVD, laser pyrolysis, flash spray pyrolysis, and melt mixing [16]. Chemical methods are the traditional and most widely used

• chapter, we introduce the basic physical mechanisms involved in the sputter deposition of materials and related processes. Low-pressure plasma-based sputter deposition, along with evaporation, cathodic arc, or laser-based deposition, belongs to the family of PVD techniques, which have been originally

Alteration of nanomechanical properties of pancreatic cancer cells through anticancer drug treatment revealed by atomic force microscopy

• Xiaoteng Liang,
• Shuai Liu,
• Xiuchao Wang,
• Dan Xia and
• Qiang Li

Beilstein J. Nanotechnol. 2021, 12, 1372–1379, doi:10.3762/bjnano.12.101

• into MIA PaCa-2, which was pre-grown for two days. The DOX solution was removed after 4 h and the cells were then washed with PBS for three times. Afterwards, the cells were cultured in normal medium for another 12 h. Laser confocal microscopy The cells (3 × 104 cells/well) were grown in 500 µL culture

• membranes were stained with Hoechst 33342 (1 µg/mL) or AF488-WGA (1 µg/mL) for 10 min. Then, the cells were rinsed three times with PBS before imaging with laser confocal microscopy. To investigate the effect of DOX on the nanostructure of MIA-PaCa-2, cell nuclei and the cytoskeleton were stained with DAPI

• (10 µg/mL) and FITC-Phalloidin (100 nM), respectively, for 30 min and 5 min. The cytoskeleton and cell nuclei were investigated by laser confocal microscopy. AFM measurement The slides with grown cells were transferred to the sample table. Then, culture medium was added both to the cell slide surface

Polarity in cuticular ridge development and insect attachment on leaf surfaces of Schismatoglottis calyptrata (Araceae)

• Venkata A. Surapaneni,
• Tobias Aust,
• Thomas Speck and
• Marc Thielen

Beilstein J. Nanotechnol. 2021, 12, 1326–1338, doi:10.3762/bjnano.12.98

• of adaxial leaf surfaces at various ontogenetic stages to study the morphological changes occurring on the leaf surfaces. We characterized the replica surfaces by using confocal laser scanning microscopy and commercial surface analysis software. The development of cuticular ridges is polar and the

• changes Figure 1 shows S. calyptrata leaves at their different ontogenetic stages (Figure 1a) and the corresponding confocal laser scanning microscopy (CLSM) observations (Figure 1b–f) on leaf microstructures. A schematic representation of the leaves and the corresponding locations of smooth and ridged

• 22.6 ± 2.6 °C and 73.5 ± 11.0%, respectively. Voucher specimens (FB 15013) of the leaves are deposited in the herbarium of Freiburg, University of Freiburg, Germany. The leaf growth was monitored from bud to adult stages. Initial trial experiments by using a confocal laser scanning microscope helped in

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

• Asylum Research’s blueDrive photothermal excitation module for laser-based excitation of the cantilever. The optical lever sensitivity (OLS) corresponding to the static cantilever beam shape with a point load at the tip was calculated from a force displacement curve [32] on the silicon sample. The

• position was recorded with an optical lever system consisting of a detection laser and a quadrant photodiode. The photodiode signal was converted into amplitude and phase at the drive frequency using a lock-in amplifier. The OLS resulting from the above calibration procedure is only valid for quasistatic

• indentation coefficient, and P is the parameter controlling the probe tip geometry. Photothermal excitation of the AFM cantilever is approximated as a pair of opposing bending moments centered at the laser spot location LbD, measured from the base of the cantilever, and separated from each other by the laser