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

• inert atmosphere or vacuum) were proposed [20], enabling depolymerization by breaking the molecular backbone bonds of PMMA [19][22][23]. Similarly, UV radiation can break the ester groups of PMMA, thus weakening the intermolecular interactions with graphene [24]. PMMA with higher AMW is harder to

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

• concentration, centrifugation was not used. Measurement equipment UV−visible spectrophotometry was performed by using a Shimadzu UV-3101PC system. Atomic force microscopy (AFM) tests were performed in a Multimode 8 system. The Raman tests were performed on a WITec alpha300 RA confocal Raman microscopy system

• concentrations of KP15 dispersions in butyrolactone were prepared by liquid exfoliation with a predetermined concentration. UV−visible absorption spectra results are shown in Figure 2. The concentration linearly varies with absorbance. The slope of this fitted linear equation is 3.86 ± 0.13. This means that the

• butyrolactone. (a) Absorbance of different concentrations of predetermined KP15 dispersions exfoliated in butyrolactone. (b) Absorbance (800 nm) as a function of concentration of predetermined KP15 dispersions. The absorption coefficient (800 nm) is 3.86 ± 0.13 mL·mg−1·cm−1. UV−visible spectrum of the KP15

Gelatin nanoparticles with tunable mechanical properties: effect of crosslinking time and loading

• Agnes-Valencia Weiss,
• Daniel Schorr,
• Julia K. Metz,
• Metin Yildirim,
• Saeed Ahmad Khan and
• Marc Schneider

Beilstein J. Nanotechnol. 2022, 13, 778–787, doi:10.3762/bjnano.13.68

• can be quantitatively measured by UV–vis spectrometry at a wavelength of λ = 349 nm related to the number of primary amines present in the equal amount of uncrosslinked gelatin. In brief, the method was as follows: 10 to 12 mg of freeze-dried particles was resuspended in 1 mL of a 4% NaHCO3 solution

• 3000 HPLC System (Thermo Fisher Scientific, Waltham, MA, USA) with a quaternary pump, a column oven, a LichroSphere® 100 RP 18 column (Merck KGaA, Darmstadt, Germany), and a UV–vis detector. The mobile phase consisted of solvent A: 10% acetonitrile, 90% MiIli-Q® water and 0.1% trifluoro acetic acid and

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

• determined according to the Brunauer−Emmett−Teller (BET) model and the Barrett−Joyner−Halenda (BJH) method. The UV–visible diffuse reflectance spectra (UV–vis DRS) were acquired on a Shimadzu UV-2450 spectrophotometer in the diffuse reflectance mode, equipped with an integrating sphere and using BaSO4 as the

• pollutant solution was taken out at set intervals to determine the concentration variation of the pollutant solution. Cr(VI) and RhB were chosen as pollutant representatives, and the concentration of the RhB aqueous solution was measured by the absorbance at λ = 553 nm, analyzed through a Shimadzu UV-2450

• water (40.0 mL) to form solution B. The Cr(VI) pollutant solution (1.0 mL), solution A (40.0 μL), and solution B (20.0 μL) were uniformly blended for 6 min, and the absorbance at λ = 540 nm of the mixed solution was recorded by a Shimadzu UV-2450 spectrophotometer to give the concentration of the

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

• PT was tested five times, and the average value was represented with standard deviation. The results also validate the standard spectrophotometric analysis. Quantification of parathion using spectrophotometry The ultraviolet–visible (UV–vis) absorption spectroscopic study was performed to validate

• the results of the proposed nanosensor. A stock solution (1 mM) of PT was prepared in 99.9% ethanol (Empura, Merck). A 5 mL volume of working solutions of 1 to 35 µM was prepared in ethanol for monitoring the UV spectra in the range of 200–400 nm with a scan rate of 2 nm/s. The absorbance change of PT

• modified electrodes was carried out in 5 mM of [Fe(CN)6]3− and [Fe(CN)6]4− with 0.1 M KCl within the frequency range from 1 MHz to 0.01 Hz, amplitude of 10 mV, at a fixed potential of 0.28 V. The UV–visible absorbance spectra were obtained on a UV–vis–NIR spectrophotometer (SHIMADZU UV-3600). The Raman

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

• influence of the photocurrent [35][36][37]. The ultraviolet (UV) light source was a He–Cd laser (Kimmon Koha) with a wavelength of 325 nm and a laser power of 2 mW. A lens was equipped on a xyz-scanner in the UHV chamber to focus the laser onto the sample with a beam diameter of 500 µm. A band-pass filter

• was arranged in front of a photodetector of the OBD system to suppress the influence of the UV light on the deflection sensor. We used a commercial Ir-coated Si cantilever (NANOSENSORS, SD-T7L100) with a resonant frequency f0 of 913 kHz, a spring constant k of 650 N/m, and a quality factor Q of 7748

• [41][42][43][44]. Rutile TiO2 has a bandgap of 3.0 eV [45] and shows the SPV under UV illumination [46][47][48]. A clean rutile TiO2(110) surface (Crystal Base) was prepared by several cycles of Ar+ sputtering (1 keV, 1 × 10−6 Torr, 15 min) and annealing (993 K, less than 2 × 10−10 Torr, 30 min

Reliable fabrication of transparent conducting films by cascade centrifugation and Langmuir–Blodgett deposition of electrochemically exfoliated graphene

• Teodora Vićentić,
• Stevan Andrić,
• Vladimir Rajić and
• Marko Spasenović

Beilstein J. Nanotechnol. 2022, 13, 666–674, doi:10.3762/bjnano.13.58

• graphene was varied. As the film of graphene formed on the surface of the water, the LB method was used to deposit the film onto the target substrate [32]. Film characterization To study optical properties of the fabricated samples, UV–vis spectroscopy was performed (Thermo Fisher Scientific EVO 60

• of the other three films, as SEM operation quickly leads to surface charging effects. Optoelectronic properties UV–vis spectra of the deposited graphene films at different centrifugation rates, redispersed in specified volumes of NMP, are given in Figure 5. The optical transmission spectra are

• the deposited graphene films decreases with increasing centrifugation rates, while Figure 3 indicates that thinner films also consist of smaller particles, which is in accordance with expectations. UV–vis spectra depicted in Figure 5 show that for a given centrifugation rate the optical transmittance

Antibacterial activity of a berberine nanoformulation

• Hue Thi Nguyen,
• Tuyet Nhung Pham,
• Anh-Tuan Le,
• Nguyen Thanh Thuy,
• Tran Quang Huy and
• Thuy Thi Thu Nguyen

Beilstein J. Nanotechnol. 2022, 13, 641–652, doi:10.3762/bjnano.13.56

• the preparation of berberine (BBR) in nanoformulation to enhance its solubility and increase its antibacterial effectiveness against hospital-acquired infections. BBR nanoparticles (BBR NPs) were formed by antisolvent precipitation (ASP) using glycerol as a safe organic solvent. UV–vis absorption

• of glycerol on the physicochemical properties of BBR NPs was investigated by UV–vis absorption and FTIR spectroscopy. The UV–vis absorption spectra of pure BBR and BBR NP solutions in distilled water at the same concentration are shown in Figure 1. Glycerol has no absorption band in the UV–vis

• spectral region because it does not possess a conjugated structure. There are peaks of three strong bands at 228, 263, and 344 nm in the UV–vis spectra of pure BBR and BBR NP solutions. These peaks characterize the π–π* transition in the BBR molecular structure. One weak band is centered at 421 nm

Sodium doping in brookite TiO₂ enhances its photocatalytic activity

• Boxiang Zhuang,
• Honglong Shi,
• Honglei Zhang and
• Zeqian Zhang

Beilstein J. Nanotechnol. 2022, 13, 599–609, doi:10.3762/bjnano.13.52

• heterojunction exhibited a synergetic effect, improving the photocatalytic activity for both hydrogen generation and organic dye degradation [10][11]). Similarly, the anatase/brookite heterojunction (38.2% brookite) also exhibited the highest degradation efficiency of cylindrospermopsin under UV–vis light [12

• activity. Results and Discussion Enhanced photocatalytic activity The photocatalytic activity of the samples calcinated at 300–600 °C for 2 h was measured by the photodegradation of MB under UV light at room temperature. Figure 1a and Figure 1b display the dynamic changes in the absorption spectra of MB

• over two typical samples (400 and 500 °C). The MB concentration versus the irradiation time was determined from the characteristic absorption peak of MB (≈665 nm) acquired by a UV–vis spectrophotometer, as shown in Figure 1c. Samples calcinated at 300 and 400 °C exhibited an excellent photocatalytic

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

• sterile water, and stored at 4 °C. The stiffness of the hydrogels with different proportions were shown in Table 1. Next, the gels were coated with a sulfo-SANPAH solution and activated in UV light at 365 nm for 10 min. These gels were then coated with type I collagen (0.1 mg·mL−1) and incubated overnight

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

• GSH-Rh6G2 was observed (Figure S3, Supporting Information File 1). GSH binds to GNPs via the thiol moiety, leading to an exposure of the amino group. Functional molecules can be directly bound via GSH, providing a stable environment based on the GNP nanostructure. The UV–vis absorption and

• were of analytical grade. TEM was carried out using a JEM-2100 transmission electron microscope (JEOL, Japan) at an accelerating voltage of 200 kV. UV–vis absorption spectra were obtained using a UV-2100 Spectrophotometer (Shimadzu, Japan). Fluorescence spectra were recorded using an F-7000

• bottle contain GNPs-GSH-Rh6G2 and GSH-Rh6G2, respectively); (c) UV–vis spectra of GNPs, GNPs-GSH, and GNPs-GSH-Rh6G2; (d) fluorescence excitation and emission spectra of GNPs-GSH-Rh6G2. DLS of (a) GNPs, (b) GNPs-GSH, and (c) GNPs-GSH-Rh6G2 (insets: TEM images); (d) zeta potential of GNPs, GNPs-GSH, and

Stimuli-responsive polypeptide nanogels for trypsin inhibition

• Petr Šálek,
• Jana Dvořáková,
• Sviatoslav Hladysh,
• Diana Oleshchuk,
• Ewa Pavlova,
• Jan Kučka and
• Vladimír Proks

Beilstein J. Nanotechnol. 2022, 13, 538–548, doi:10.3762/bjnano.13.45

• loaded with AAT (0.102 and 0.051 mg) for 24 h. The assay was prepared by mixing of BAEE solution (2 mL, 0.37 mM) in PBS buffer (pH 7.6) with 1 mM HCl (0.125 mL), dispersion of AAT loaded-PHEG-Tyr, or AAT loaded-Nα-Lys-NG, nanogel (1 mL), and trypsin solution (0.075 mL) in 1 mM HCl in cuvettes for UV–vis

• , 0.375 mM) in PBS buffer (pH 7.6) with 1 mM HCl (0.125 mL) and trypsin solution (0.075 mL) in 1 mM HCl in cuvettes for UV–vis spectrophotometric measurements. Immediately after mixing, the absorbance at λ = 253 nm was recorded for 5 or 15 min using 1 min time intervals. The blank solutions were prepared

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

• substrates were first cleaned in a 1% Hellmanex solution at 70 °C for 30 min in an ultrasonic bath, then washed three times in distilled water, dried by nitrogen flow, and finally treated in a UV ozone chamber for 5 min to obtain the cleaned FTO electrode. Precursor solutions were prepared by dissolving (NH4

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

• and skin The analysis of ciprofloxacin was adopted from the United States Pharmacopoeia (USP) and was performed using HPLC (Shimadzu HPLC, model LC-2030C PLUS 3D). The system included an integrated solvent and degasser, an analytical pump, a thermostatic autosampler, a UV detector, and a thermostatic

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

• sodium carbonate solution. The extracts were analyzed using a high-performance liquid chromatograph coupled to a UV–vis spectrophotometric detector. For the detection of polyphenols, chrysin and p-coumaric acid (analytical standard) at a wavelength (λ) of 310 nm were used as markers. At least three

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

• ultraviolet (UV) radiation, smoking, pollution, and normal endogenous metabolic processes triggers the skin aging process. Elastase and collagenase enzymes induced by the formation of ROS accelerate the aging process and cause loss of collagen and elastin fibrils. With the formation of free radicals, lipid

• study conducted by Gwak et al., the effect on the stability of ETHs developed to prevent the degradation of EGCG under different storage conditions was observed. The stability values of the solution and the ethosomal formulation of EGCG upon exposure to UV or high temperature were compared, and it was

• noted that the degradation of EGCG under UV was delayed by the ETHs and by the incorporation of tocopherol as an antioxidant in the formulation [35]. In another study, cream-based formulations of different vesicular systems (liposomes, ethosomes, and transfersomes) containing Curcuma longa extract were

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

• their wide bandgap energy (3.3–3.7 eV), strong luminescence [4][5], antibacterial properties, and UV-protection properties. Additionally, ZnO nanomaterials can be designed into various morphologies, such as nanoparticles, nanoneedles, nanorods, nanocages, nanocombs, and nanoflowers [5][6][7][8]. Hybrid

• nanostructures, however, are significantly inferior to those on noble metals since the LSPR is centred in the near-infrared in the case of the conduction band (CB) and in the UV region in the case of the valence band (VB) [14]. Therefore, concrete solutions have been proposed to improve the EM enhancement in ZnO

• when used as a SERS substrate. The self-cleaning ability of ZnO alone or ZnO–noble metal-based nanostructured substrates has been shown under UV or visible irradiation via the photocatalytic degradation of the organic molecules attached to the substrate [8][34][53]. For instance, [75] presented Au

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• tailor surface properties [13][14][15][16][17][18][19][20]. These monolayers can be modified with lithographic tools, such as scanning probes [21], UV light, X-rays, ions, or electron beams [22][23][24]. A particularly versatile nanofabrication scheme utilizes electron irradiation of aromatic SAMs to

• substrate was cleaned in a UV/ozone cleaner (UVOH 150 LAB FHR) for 3 min, rinsed with ethanol, and then blown dry under a nitrogen stream. The substrates were immersed into a ≈1 mM solution of TPT in dry and degassed dimethylformamide. The solution was then heated at 70 °C in a sealed flask under a nitrogen

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

• after centrifuging and washing with water and, subsequently, dissolved in 0.1 M NaOH solution. The concentrations of Myr and GSH were determined by UV–vis spectroscopy. The concentration of Zn2+ was measured by inductively coupled plasma optical emission spectroscopy (ICP-OES). Evaluation of ROS

• scavenging activity First, a solution of 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical cations (ABTS+) solution was prepared. 7 mM of ABTS solution was mixed with 2.45 mM of potassium persulfate solution and kept for 12 h in the dark. The UV–vis absorption intensity of a 0.7 mM ABTS solution

• (diluted in PBS) was 0.7 ± 0.02. A certain volume of diluted ABTS+ solution was added to different concentrations of Myr, GSH, and MZG. A UV–vis spectrophotometer was used to record the absorption intensity of ABTS+ at 734 nm. The radical scavenging rate was calculated according to the following equation

Investigation of a memory effect in a Au/(Ti–Cu)Ox-gradient thin film/TiAlV structure

• Damian Wojcieszak,
• Jarosław Domaradzki,
• Michał Mazur,
• Tomasz Kotwica and
• Danuta Kaczmarek

Beilstein J. Nanotechnol. 2022, 13, 265–273, doi:10.3762/bjnano.13.21

• of the current-to-voltage measurements. On the basis of the performed investigations, we suggest that the conducting filament switching is the most probable mechanism. This is supported by investigations of structure and surface properties using X-ray methods, UV photoelectron spectroscopy, and cross

Effects of drug concentration and PLGA addition on the properties of electrospun ampicillin trihydrate-loaded PLA nanofibers

• Tuğba Eren Böncü and
• Nurten Ozdemir

Beilstein J. Nanotechnol. 2022, 13, 245–254, doi:10.3762/bjnano.13.19

• ). After evaporation of DCM, the volume of each solution was completed to 10 mL with buffer and the amount of ampicillin trihydrate was analyzed using a UV spectrophotometer (Thermo Scientific Evolution 201). The encapsulation efficiency of the nanofibers was calculated using the following equation

• ) at 37 °C (n = 3). All of the released medium was removed and 5 mL of fresh solution was added at predetermined time intervals. The amount of drug released was assayed using a UV spectrophotometer. For calibration and validation of ampicillin trihydrate release, solutions were prepared at 2.5–30 µg/mL

Surfactant-free syntheses and pair distribution function analysis of osmium nanoparticles

• Mikkel Juelsholt,
• Jonathan Quinson,
• Emil T. S. Kjær,
• Baiyu Wang,
• Rebecca Pittkowski,
• Susan R. Cooper,
• Tiffany L. Kinnibrugh,
• Søren B. Simonsen,
• Luise Theil Kuhn,
• María Escudero-Escribano and
• Kirsten M. Ø. Jensen

Beilstein J. Nanotechnol. 2022, 13, 230–235, doi:10.3762/bjnano.13.17

• closed containers made of polypropylene, which were heated to 90 °C for 6 h using an oil bath. As opposed to a classical reflux setup using glassware [22] or to the use of microwaves [30], visible or UV light [31], this allowed for a rapid screening of a number of experimental parameters for long

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

• precursor [Ru(acetone)6](PF6)3 (Ru-PF6) were prepared according to procedures previously described [15][19][25][26][27]. The analysis of the prepared substances, including 1H NMR, UV–vis spectroscopy and mass spectrosmetry, display a high purity [15]. The molecular formulas of the chemical compounds are

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

• become superhydrophilic under UV light, function well as photosensitizer. Subsequently, another study established the use of nanoscale TiO2 as a redox coating of in implants [9]. Titanium and its alloys are considered the most promising materials for implants due to their superior properties, which

• minimize the risk of device-related infections, implants are usually coated with TiO2 nanotubes, which under UV irradiation, generate reactive oxygen species (ROS), resulting in the disinfection ability [13]. One of the most vital contributions of nanotechnology is the development of novel modes of drug

• photocatalytic activity. Upon UV irradiation, the electrons in the valence band get excited to the conduction band, leading to the formation of electron–hole pairs and the generation of ROS. Subsequently, the generated holes (h+) convert water/hydroxide molecules to peroxide/hydroxyl radicals by oxidation. The

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

• degradation. The membrane displayed an efficient photocatalytic capacity for MB, CR, and RhB [80]. Although TiO2 is abundant and inexpensive, it only converts to UV part of sunlight, which is only 5% of the solar energy. This makes the use of TiO2 impractical. To counter this drawback Liu and co-workers