Time-dependent growth of crystalline Au⁰-nanoparticles in cyanobacteria as self-reproducing bioreactors: 2. Anabaena cylindrica

• Liz M. Rösken,
• Felix Cappel,
• Susanne Körsten,
• Christian B. Fischer,
• Andreas Schönleber,
• Sander van Smaalen,
• Stefan Geimer,
• Christian Beresko,
• Georg Ankerhold and
• Stefan Wehner

Beilstein J. Nanotechnol. 2016, 7, 312–327, doi:10.3762/bjnano.7.30

• electron microscope. These images reveal the spatial distribution of the nanoparticles inside the cells as it was in the moment when their biosynthesis was stopped. Laser-induced breakdown spectroscopy In recent years UV–vis spectroscopy has often been used for the in situ observation of nanoparticle or

• nanocluster development [46][47][48] of various metals, e.g., palladium, gold and silver [46]. Although UV–vis spectroscopy based methods have been developed to determine the size of nanoparticles resp. nanoclusters in solution [47][48]. UV–vis spectroscopy was also tested for the type of system used here in

Single-molecule mechanics of protein-labelled DNA handles

• Vivek S. Jadhav,
• Dorothea Brüggemann,
• Florian Wruck and
• Martin Hegner

Beilstein J. Nanotechnol. 2016, 7, 138–148, doi:10.3762/bjnano.7.16

• kb DNA ladder (NEB & Promega). We utilized UV–vis spectroscopy (Nanodrop spectrophotometer ND-1000, Fisher Scientific, Dublin, Ireland) to measure the concentration of the DHs and PDH constructs. These measurements were also indicative for the presence of protein after 90 min of incubation and the

Impact of ultrasonic dispersion on the photocatalytic activity of titania aggregates

• Hoai Nga Le,
• Frank Babick,
• Klaus Kühn,
• Minh Tan Nguyen,
• Michael Stintz and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2015, 6, 2423–2430, doi:10.3762/bjnano.6.250

• , the transmittance of the 100× diluted samples from the original 1 g/L suspensions were measured. In order to measure the amount of MB remaining in the solution for the discoloration tests, we measured the absorbance in the supernatant suspensions through 10 mm optical path length by UV–vis

• spectroscopy. The MB concentrations were calibrated from the absorbance at λ = 664 nm [19] (the calibration curve can be found in Figure S2 of Supporting Information File 1) and are plotted as a function of irradiation time. Results and Discussion Verification of the kinetic model In essence, an increase of

Green synthesis, characterization and catalytic activity of natural bentonite-supported copper nanoparticles for the solvent-free synthesis of 1-substituted 1H-1,2,3,4-tetrazoles and reduction of 4-nitrophenol

• Akbar Rostami-Vartooni,
• Mohammad Alizadeh and
• Mojtaba Bagherzadeh

Beilstein J. Nanotechnol. 2015, 6, 2300–2309, doi:10.3762/bjnano.6.236

• concentration of 4-NP was monitored at given intervals by using UV–vis spectroscopy and the results are shown in Figure 9. The original absorption peak of 4-NP is centered at about 320 nm and shifts to 400 nm after addition of the NaBH4 solution. This is due to the formation of p-nitrophenolate ions under

Selective porous gates made from colloidal silica nanoparticles

• Roberto Nisticò,
• Paola Avetta,
• Paola Calza,
• Debora Fabbri,
• Giuliana Magnacca and
• Dominique Scalarone

Beilstein J. Nanotechnol. 2015, 6, 2105–2112, doi:10.3762/bjnano.6.215

• range 1–2 nm, probably due to intraparticle voids generated from the elimination of poly(ethylene-oxide) moieties during the calcination step [41]. Transport testing of the functional coating UV–vis spectroscopy was used to study the diffusion of two positively charged chemical probes (i.e., MB and

• Aquamarijn Micro Filtration BV (Zutphen, Netherlands), having on top a Si3N4 membrane (5 mm × 5 mm × 0.6 mm) with macropores arranged in a hexagonal setting and diameter of 5 μm. Supporting Information Supporting Information File 144: External calibration curves performed by UV–vis spectroscopy

A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• heterostructures were characterized by X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence (PL) spectroscopy. The PL spectra of Mn:ZnS/ZnS/Fe3O4 quantum dots (QDs) showed marked visible emission around 584 nm related to the 4T1

Synthesis, characterization and in vitro biocompatibility study of Au/TMC/Fe₃O₄ nanocomposites as a promising, nontoxic system for biomedical applications

• Hanieh Shirazi,
• Maryam Daneshpour,
• Soheila Kashanian and
• Kobra Omidfar

Beilstein J. Nanotechnol. 2015, 6, 1677–1689, doi:10.3762/bjnano.6.170

• ) TMC, (c) chitosan/Fe3O4, (d) TMC/Fe3O4, (e) Au/chitosan/Fe3O4, and (f) Au/TMC/Fe3O4. UV–vis spectroscopy of Au nanoparticles as a function of (a) Au nanoparticle concentration and (b) reaction time. TEM images of (a) Au/TMC/Fe3O4 and (c) Au/chitosan/Fe3O4 with respective particle size distributions (b

Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles

• Simon Ristig,
• Svitlana Chernousova,
• Wolfgang Meyer-Zaika and
• Matthias Epple

Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124

• important factor for subsequent in vitro experiments) was carried out by multiple ultracentrifugation steps. Characterization by transmission electron microscopy (TEM), differential centrifugal sedimentation (DCS), dynamic light scattering (DLS), UV–vis spectroscopy and atomic absorption spectroscopy (AAS

• scattering was monitored at a fixed angle of 173° in backward scattering mode. The primary data were derived from the correlation function of the scattered intensity as a number-weighed size distribution. UV–vis spectroscopy was performed with a Varian Cary 300 instrument. Suprasil® cuvettes with a sample

• /Au nanoparticles and pure Ag and Au nanoparticles. Overview of the absorption maxima in UV–vis spectroscopy of PVP-functionalized Ag/Au nanoparticles as function of the experimentally determined silver molar content (Table 2). The viability of HeLa cells after incubation with alloyed nanoparticles

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

Morphology control of zinc oxide films via polysaccharide-mediated, low temperature, chemical bath deposition

• Florian Waltz,
• Hans-Christoph Schwarz,
• Andreas M. Schneider,
• Stefanie Eiden and
• Peter Behrens

Beilstein J. Nanotechnol. 2015, 6, 799–808, doi:10.3762/bjnano.6.83

• CBD steps, HYA was added at different time intervals in order to optimize the quality of the resulting films. The properties of the films were studied by means of field emitting scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UV–vis spectroscopy and electrical conductivity measurements

Tm-doped TiO₂ and Tm₂Ti₂O₇ pyrochlore nanoparticles: enhancing the photocatalytic activity of rutile with a pyrochlore phase

• Desiré M. De los Santos,
• Javier Navas,
• Teresa Aguilar,
• Antonio Sánchez-Coronilla,
• Concha Fernández-Lorenzo,
• Rodrigo Alcántara,
• Jose Carlos Piñero,
• Ginesa Blanco and
• Joaquín Martín-Calleja

Beilstein J. Nanotechnol. 2015, 6, 605–616, doi:10.3762/bjnano.6.62

• spectroscopy and UV–vis spectroscopy. For the samples annealed at 773 and 973 K, anatase phase TiO2 was obtained, predominantly internally doped with Tm3+. ICP–AES showed that a doping concentration of up to 5.8 atom % was obtained without reducing the crystallinity of the samples. The presence of Tm3+ was

• confirmed by X-ray photoelectron spectroscopy and UV–vis spectroscopy: the incorporation of Tm3+ was confirmed by the generation of new absorption bands that could be assigned to Tm3+ transitions. Furthermore, when the samples were annealed at 1173 K, a pyrochlore phase (Tm2Ti2O7) mixed with TiO2 was

• study the optical properties of the samples and to determine the band gap energy, UV–vis spectroscopy in diffuse reflectance (DR–UV–vis) mode was used. The custom-built system was composed of: (i) an integrating sphere (Spectra Tech), (ii) a spectrometer (USB2000+, Ocean Optics), and (iii) a xenon lamp

Novel ZnO:Ag nanocomposites induce significant oxidative stress in human fibroblast malignant melanoma (Ht144) cells

• Syeda Arooj,
• Samina Nazir,
• Akhtar Nadhman,
• Nafees Ahmad,
• Bakhtiar Muhammad,
• Ishaq Ahmad,
• Kehkashan Mazhar and
• Rashda Abbasi

Beilstein J. Nanotechnol. 2015, 6, 570–582, doi:10.3762/bjnano.6.59

• performing assays, we dialyzed our ZnO:Ag nanocomposite suspensions with Spectra Por 6 (mw cutoff 25000) Spectrum® dialysis membrane for 4 h against deionized water. Characterization of nanocomposite The nanocomposites were characterized by SEM, XRD, Rutherford back scattering, UV–vis spectroscopy and DRS

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• was then amine-functionalized through APS treatment for bioconjugation with FITC-IgG by using glutaraldehyde as linker. The characterization of the prepared NPs was carried out through XRD, UV–vis spectroscopy and PL emission spectra, VSM, TEM and SEM. The fluorescence spectra of mercaptosuccinic-acid

• –vis spectroscopy. The decrease in the absorbance band at 400 nm suggested the successful photogeneration of singlet oxygen. The biocompatibility of these nanocomposites was studied by incubating these nanocomposites with human hepatocyte cells (QSG-7701) for 24 h. The results indicated that even after

• 2.5 nm. When the hybrid nanocomposite material was excited at 488 nm, it exhibited only one emission peak at 520 nm corresponding to fluorescein. The effectiveness of these nanocomposites to generate singlet oxygen (1O2) upon light irradiation was studied using 1,3-diphenylisobenzofuran (DPBF) by UV

Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires

• Alberto Milani,
• Matteo Tommasini,
• Valeria Russo,
• Andrea Li Bassi,
• Andrea Lucotti,
• Franco Cataldo and
• Carlo S. Casari

Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49

• described in detail in [64]. When the discharge is operated in methanol it is possible to obtain polyynes with an even number of carbon atoms (6 ≤ C ≤ 16) terminated by one hydrogen atom on each side. The size distribution obtained from HPLC complemented with UV–vis spectroscopy is reported in Figure 4

Release behaviour and toxicity evaluation of levodopa from carboxylated single-walled carbon nanotubes

• Julia M. Tan,
• Jhi Biau Foo,
• Sharida Fakurazi and
• Mohd Zobir Hussein

Beilstein J. Nanotechnol. 2015, 6, 243–253, doi:10.3762/bjnano.6.23

• materials characterization methods including Fourier transform infrared spectroscopy, Raman spectroscopy, elemental analysis, UV–vis spectroscopy and scanning electron microscopy. The results showed that SWCNT–COOH were able to form supramolecular complexes with LD via a π–π stacking interaction and

• ≈38.2% as determined by UV–vis spectroscopy. Fourier transform infrared spectra indicated that the LD was successfully conjugated to SWCNT–COOH, and this was further supported by both the CHNS elemental analysis and Raman spectroscopy study. The drug release study shows that the release of LD from SWCNT

• allowed to cool to room temperature for another 30 min. This ensured that the LD was fully dissolved in deionized water. After that, the solution was scanned in range of 200–600 nm to determine the maximum absorption wavelength, λmax, of LD (as referenced to a blank reagent) by UV–vis spectroscopy. The

Mechanical properties of MDCK II cells exposed to gold nanorods

• Anna Pietuch,
• Bastian Rouven Brückner,
• David Schneider,
• Marco Tarantola,
• Christina Rosman,
• Carsten Sönnichsen and
• Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21

• of gold nanorods were obtained from UV–vis spectroscopy using their optical extinction value at 400 nm and a molar extinction coefficient of 1.1 × 109 Lmol−1cm−1 assuming the aforementioned particle size found by TEM. In order to replace the CTAB, functionalized polyethylene glycol thiols (X-PEG-SH

Increasing throughput of AFM-based single cell adhesion measurements through multisubstrate surfaces

• Miao Yu,
• Nico Strohmeyer,
• Jinghe Wang,
• Daniel J. Müller and
• Jonne Helenius

Beilstein J. Nanotechnol. 2015, 6, 157–166, doi:10.3762/bjnano.6.15

• replaced after characterizing 4 cells on each coating. If a cell showed morphological changes during the experiments, it was discarded. Adhesion forces were extracted from force–distance curves using JPK data processing software. Fluorescence microscopy and UV–vis spectroscopy Fluorescence microscopy was

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• normal MRC-5 fibroblast lung cells were investigated [76]. The hemolytic activity of the pure BNNTs was investigated by UV–vis spectroscopy and the results showed no significant hemolysis of cells that were exposed to the BNNTs. The metabolic activity of the BNNT-exposed cells using an MTT assay was

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

• Rudolf Herrmann,
• Markus Rennhak and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

• the amount of dye molecules at the surface is sufficiently high to be detectable by UV–vis spectroscopy, one can in principle use absorption for photometric determination. The problem with this approach is the strong light scattering by the NP which overlays the absorption. We therefore developed a

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• oxide domains of the heterodimer nanoparticles were adjusted by a precise control of the precursor ratio, the number of seed particles, and the heating profile. Optical characteristics of Au@MOx Janus particles Figure 10 shows the dependence of the absorption maximum measured by UV–vis spectroscopy from

• size dependency of absorption maximum of Au@MnO nanoparticles determined by UV–vis spectroscopy in comparison to pristine Au nanoparticles. UV–vis spectra of Au (solid), Au@MnO (dashed), and Au@Fe3O4 (dotted) nanoparticles normalized to the absorption at 800 nm. Schematic representation of the

Influence of stabilising agents and pH on the size of SnO₂ nanoparticles

• Olga Rac,
• Patrycja Suchorska-Woźniak,
• Marta Fiedot and
• Helena Teterycz

Beilstein J. Nanotechnol. 2014, 5, 2192–2201, doi:10.3762/bjnano.5.228

• concentration was changed, while the amount of other components was held constant. Characterisation of SnO2 nanoparticles UV–vis spectroscopy: Spectroscopic studies were performed using an Evolution 201 UV–vis spectrophotometer from Thermo Scientific. The studies were performed at 23 °C in quartz cuvettes

Carbon nano-onions (multi-layer fullerenes): chemistry and applications

• Juergen Bartelmess and
• Silvia Giordani

Beilstein J. Nanotechnol. 2014, 5, 1980–1998, doi:10.3762/bjnano.5.207

• ) and H2. The successful fluorination led to an increase of the mass of the CNO material and the fluorinated CNOs (F-CNO) were well soluble in ethanol and other alcohols as well as in DMF. Characterization of the F-CNOs was carried out by a multitude of techniques such as FTIR, Raman and UV–vis

• spectroscopy, SEM/EDX, XRD, XPS, TGA and TEM. In addition, the authors reported that the fluorination of the F-CNOs was reversible upon treatment with hydrazine, which interestingly led also to a regeneration of the “broken” graphene layers of the CNO. Some years later, based on the F-CNO material, the same

Imaging the intracellular degradation of biodegradable polymer nanoparticles

• Anne-Kathrin Barthel,
• Martin Dass,
• Melanie Dröge,
• Jens-Michael Cramer,
• Daniela Baumann,
• Markus Urban,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2014, 5, 1905–1917, doi:10.3762/bjnano.5.201

• achieved and applied on a copper grid (3.05, 300 mesh, Agar Scientific, U.K.). The sections were observed in a Zeiss EM 912 transmission electron microscope with a tungsten filament at an acceleration voltage of 120 kV. Micrographs were taken via a Cantega Olympus slow scan CCD camera. UV−visible (UV−vis

• ) spectroscopy A Lambda 25 (Perkin-Elmer) UV−vis spectrometer was used to monitor the formation of the FeCl(H2O)52+ complex upon addition of HCl to magnetite particles. The FeCl(H2O)52+ complex shows a characteristic absorption band at 340 nm. The cell was filled with 3 mL of diluted HCl (28 wt %) for background

In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics

• Wolfgang G. Kreyling,
• Stefanie Fertsch-Gapp,
• Martin Schäffler,
• Blair D. Johnston,
• Nadine Haberl,
• Christian Pfeiffer,
• Jörg Diendorf,
• Carsten Schleh,
• Stephanie Hirn,
• Manuela Semmler-Behnke,
• Matthias Epple and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1699–1711, doi:10.3762/bjnano.5.180

• previous physicochemical characterizations [8], all AuNP used in these experiments were thoroughly characterized through TEM (size distribution), UV–vis spectroscopy (absorbance), dynamic light scattering (DLS, hydrodynamic diameter), differential centrifugal sedimentation (DCS) and atomic force microscopy

The influence of molecular mobility on the properties of networks of gold nanoparticles and organic ligands

• Edwin J. Devid,
• Paulo N. Martinho,
• M. Venkata Kamalakar,
• Úna Prendergast,
• Christian Kübel,
• Tibebe Lemma,
• Jean-François Dayen,
• Tia. E. Keyes,
• Bernard Doudin,
• Mario Ruben and
• Sense Jan van der Molen

Beilstein J. Nanotechnol. 2014, 5, 1664–1674, doi:10.3762/bjnano.5.177

• volume. UV–vis spectroscopy Ultraviolet-visible (UV–vis) spectroscopy is performed to gain insight into the optical properties of these molecule–gold nanoparticle arrays, and specifically to investigate the influence of the S-BPP molecules on the effective dielectric constant. Metal nanoparticles exhibit

• . This is also confirmed experimentally from UV–vis spectroscopy of a C8–gold nanoparticle dispersion and a S-BPP–gold nanoparticle dispersion (both in chloroform), in which effectively f = 0. In Figure S9 (see Supporting Information File 1) we show that the SPR peak of the S-BPP-covered gold

• . Second, UV–vis spectroscopy indicates that εm (and also εeff which incorporates f) is actually higher for Au-NP–S-BPP networks than for alkanethiol networks (see Table 1). This should thus lead to a lower charging energy for S-BPP than for octanethiol networks and hence to linear I–V-curves at room