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Search for "UV–vis spectroscopy" in Full Text gives 144 result(s) in Beilstein Journal of Nanotechnology.

Fully amino acid-based hydrogel as potential scaffold for cell culturing and drug delivery

  • Dávid Juriga,
  • Evelin Sipos,
  • Orsolya Hegedűs,
  • Gábor Varga,
  • Miklós Zrínyi,
  • Krisztina S. Nagy and
  • Angéla Jedlovszky-Hajdú

Beilstein J. Nanotechnol. 2019, 10, 2579–2593, doi:10.3762/bjnano.10.249

Graphical Abstract
  • of the release of metoprolol is diffusion. Moreover, metoprolol can be measured easily beside DTT by UVvis spectroscopy. The kinetics of the metoprolol release from the different PASP-XCYS-LYS gels was studied in both physiological saline (NaCl) and DTT solution (Figure 7). The graph depicts the
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Published 27 Dec 2019

Long-term stability and scale-up of noncovalently bound gold nanoparticle-siRNA suspensions

  • Anna V. Epanchintseva,
  • Julia E. Poletaeva,
  • Dmitrii V. Pyshnyi,
  • Elena I. Ryabchikova and
  • Inna A. Pyshnaya

Beilstein J. Nanotechnol. 2019, 10, 2568–2578, doi:10.3762/bjnano.10.248

Graphical Abstract
  • siRNA duplex integrity as well as siRNA surface density. Dynamic light scattering, transmission electron microscopy, UVvis spectroscopy, and electrophoresis were used to study the effect of scaling up the AuNP-siRNA synthesis and long term storage of its suspension on physicochemical properties of the
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Published 23 Dec 2019

Targeted therapeutic effect against the breast cancer cell line MCF-7 with a CuFe2O4/silica/cisplatin nanocomposite formulation

  • B. Rabindran Jermy,
  • Vijaya Ravinayagam,
  • Widyan A. Alamoudi,
  • Dana Almohazey,
  • Hatim Dafalla,
  • Lina Hussain Allehaibi,
  • Abdulhadi Baykal,
  • Muhammet S. Toprak and
  • Thirunavukkarasu Somanathan

Beilstein J. Nanotechnol. 2019, 10, 2217–2228, doi:10.3762/bjnano.10.214

Graphical Abstract
  • saline solution. The presence of cubic spinel CuFe2O4 on HYPS was confirmed through powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR) and diffuse reflectance UVvis spectroscopy (DR UV–vis) analysis. The HYPS particles showed a surface area of 170 m2/g, pore size of 8.3 nm
  • multifunctional biomedical applications. The crystalline phase, morphology, magnetization, and coordination environment of various spinel species were characterized using X-ray diffraction (XRD), BET surface area measurements, vibrating sample magnetometry (VSM), diffuse reflectance UVvis spectroscopy (DR UV–vis
  • temperature at 37 °C. At regular time intervals, a specific volume of solution was removed (10 mL) and analyzed using UVvis spectroscopy. The withdrawn solution was replaced with an equal volume of fresh PBS solution. In vitro study on MCF-7 cells In this study, the antitumor effect of cisplatin-loaded 30 wt
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Published 12 Nov 2019

Porous silver-coated pNIPAM-co-AAc hydrogel nanocapsules

  • William W. Bryan,
  • Riddhiman Medhi,
  • Maria D. Marquez,
  • Supparesk Rittikulsittichai,
  • Michael Tran and
  • T. Randall Lee

Beilstein J. Nanotechnol. 2019, 10, 1973–1982, doi:10.3762/bjnano.10.194

Graphical Abstract
  • . The morphology and composition of the composite nanoparticles were characterized by SEM, TEM, and FTIR, respectively. UVvis spectroscopy was used to characterize the optical properties. Keywords: hydrogels; nanocapsules; photothermal delivery; poly(NIPAM); porous silver shells; Introduction
  • -growth method and surfactant-free emulsion polymerization, we demonstrated a reliable synthesis of silver nanocapsules encapsulating thermo-responsive pNIPAM-co-AAc hydrogel cores. The 800 nm silver nanocapsules with a capsule thickness of ≈50 nm were characterized by SEM, TEM, and UVvis spectroscopy
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Published 04 Oct 2019

Preservation of rutin nanosuspensions without the use of preservatives

  • Pascal L. Stahr and
  • Cornelia M. Keck

Beilstein J. Nanotechnol. 2019, 10, 1902–1913, doi:10.3762/bjnano.10.185

Graphical Abstract
  • reduced DPPH can be accessed via UVvis spectroscopy. For the determination of the IC50 values, 100 µL of the samples containing different concentrations of the nanocrystals (200, 100, 50, 25, 12.5, 6.25, 3.125 µg/mL) were added to 100 µL of a 0.3 mM methanolic solution of DPPH. After 30 min incubation
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Published 19 Sep 2019

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

  • Manuel Souto,
  • Joaquín Calbo,
  • Samuel Mañas-Valero,
  • Aron Walsh and
  • Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

Graphical Abstract
  • needle-like morphology of C60@MUV-2 also remained similar to the one of MUV-2 as confirmed by scanning electron microscopy (SEM) (Figure S1, Supporting Information File 1). Raman and UVvis spectroscopy Raman spectra of C60, MUV-2 and C60@MUV-2 crystals were measured using a Raman excitation wavelength
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Published 18 Sep 2019

Highly ordered mesoporous silica film nanocomposites containing gold nanoparticles for the catalytic reduction of 4-nitrophenol

  • Mohamad Azani Jalani,
  • Leny Yuliati,
  • Siew Ling Lee and
  • Hendrik O. Lintang

Beilstein J. Nanotechnol. 2019, 10, 1368–1379, doi:10.3762/bjnano.10.135

Graphical Abstract
  • ) measurements were carried out at on a Bruker D8 Advance diffractometer with Cu Kα radiation. Ultraviolet–visible (UV–vis) spectra were recorded on a Thermo Scientific model GENESYS 10S UVvis spectroscopy. Transmission electron microscopy (TEM) images were obtained by using a JEOL JEM-2100 device operating at
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Published 05 Jul 2019

A highly efficient porous rod-like Ce-doped ZnO photocatalyst for the degradation of dye contaminants in water

  • Binjing Hu,
  • Qiang Sun,
  • Chengyi Zuo,
  • Yunxin Pei,
  • Siwei Yang,
  • Hui Zheng and
  • Fangming Liu

Beilstein J. Nanotechnol. 2019, 10, 1157–1165, doi:10.3762/bjnano.10.115

Graphical Abstract
  • Wuxi ZhanWang Chemical Reagent Co., LTD. 2-methylimidazole was provided by Shanghai Bide Pharmaceutical Technology Co., LTD. All other reagents used were purchased from Sinopharm Group Chemical Reagent Co., LTD. A Newport 94023A (USA) device was used as the sunlight stimulator. The UVvis spectroscopy
  • centrifuged before this process began. The supernatant was diluted with an equal amount of deionized water, then taken out for the measurement of absorbance (A0) at 554 nm by UVvis spectroscopy. Every 20 min the sampling process was repeated, and the absorbance was determined. The degradation rate (DR) was
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Published 03 Jun 2019

Fabrication of silver nanoisland films by pulsed laser deposition for surface-enhanced Raman spectroscopy

  • Bogusław Budner,
  • Mariusz Kuźma,
  • Barbara Nasiłowska,
  • Bartosz Bartosewicz,
  • Malwina Liszewska and
  • Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2019, 10, 882–893, doi:10.3762/bjnano.10.89

Graphical Abstract
  • measurements of the chemical composition of the fabricated SNIFs by using X-ray photoelectron spectroscopy (XPS) and their optical properties by using UVvis spectroscopy. Finally, we describe the SERS performance of SNIFs in the measurements of para-mercaptoaniline (pMA) molecules. Results and Discussion
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Published 16 Apr 2019

Reduced graphene oxide supported C3N4 nanoflakes and quantum dots as metal-free catalysts for visible light assisted CO2 reduction

  • Md Rakibuddin and
  • Haekyoung Kim

Beilstein J. Nanotechnol. 2019, 10, 448–458, doi:10.3762/bjnano.10.44

Graphical Abstract
  • , X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy (TEM), and UVvis spectroscopy. High-resolution TEM images clearly show that C3N4 QDs (average diameter of 2–3 nm) and NFs (≈20–45 nm) are
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Published 13 Feb 2019

Gold nanoparticles embedded in a polymer as a 3D-printable dichroic nanocomposite material

  • Lars Kool,
  • Anton Bunschoten,
  • Aldrik H. Velders and
  • Vittorio Saggiomo

Beilstein J. Nanotechnol. 2019, 10, 442–447, doi:10.3762/bjnano.10.43

Graphical Abstract
  • change during the synthesis hints that the dichroic nanoparticle formation is not just seeded growth, but a more complex mechanism. Therefore, we studied the evolution of the nanoparticle formation over time using UVvis spectroscopy and TEM (Supporting Information File 1, Figures S3 and S4). The time
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Published 12 Feb 2019

Thermal control of the defunctionalization of supported Au25(glutathione)18 catalysts for benzyl alcohol oxidation

  • Zahraa Shahin,
  • Hyewon Ji,
  • Rodica Chiriac,
  • Nadine Essayem,
  • Franck Rataboul and
  • Aude Demessence

Beilstein J. Nanotechnol. 2019, 10, 228–237, doi:10.3762/bjnano.10.21

Graphical Abstract
  • S1, Supporting Information File 1). The transmission electron microscopy (TEM) image shows that the ZrO2 particles have a diameter of around 50 nm. Au25(SG)18 was synthesized according to a reported method [33]. The characterization of the clusters by UVvis spectroscopy shows two absorption peaks
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Published 18 Jan 2019

New micro/mesoporous nanocomposite material from low-cost sources for the efficient removal of aromatic and pathogenic pollutants from water

  • Emmanuel I. Unuabonah,
  • Robert Nöske,
  • Jens Weber,
  • Christina Günter and
  • Andreas Taubert

Beilstein J. Nanotechnol. 2019, 10, 119–131, doi:10.3762/bjnano.10.11

Graphical Abstract
  • FTIR, 4000–400 cm−1, 40 Scans) using KBr pellets prepared with a Shimadzu MHP-1 mini hand press. The background correction was performed with a pure KBr pellet, and the samples were measured at 10% in 90% KBr. UVvis spectroscopy was performed on a Shimadzu 1650pc UV–vis spectrophotometer for analysis
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Published 09 Jan 2019

Comparative biological effects of spherical noble metal nanoparticles (Rh, Pd, Ag, Pt, Au) with 4–8 nm diameter

  • Alexander Rostek,
  • Marina Breisch,
  • Kevin Pappert,
  • Kateryna Loza,
  • Marc Heggen,
  • Manfred Köller,
  • Christina Sengstock and
  • Matthias Epple

Beilstein J. Nanotechnol. 2018, 9, 2763–2774, doi:10.3762/bjnano.9.258

Graphical Abstract
  • backward scattering mode. The primary data were derived from the correlation function of the scattered intensity as a number-weighed size distribution. Ultraviolet–visible (UVvis) spectroscopy was performed with a Varian Cary 300 instrument from 200 to 800 nm with background correction. Suprasil® cuvettes
  • [89]. It was shown by Ino that metal nanoparticles (Ag, Au, Cu, Pd, Pt) prefer an icosahedral structure if their diameter is smaller than approximately 10 nm. Nanocrystals with larger diameters prefer the shape of a truncated octahedron [88][90]. UVvis spectroscopy gives information on the optical
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Published 29 Oct 2018

Impact of the anodization time on the photocatalytic activity of TiO2 nanotubes

  • Jesús A. Díaz-Real,
  • Geyla C. Dubed-Bandomo,
  • Juan Galindo-de-la-Rosa,
  • Luis G. Arriaga,
  • Janet Ledesma-García and
  • Nicolas Alonso-Vante

Beilstein J. Nanotechnol. 2018, 9, 2628–2643, doi:10.3762/bjnano.9.244

Graphical Abstract
  • surface of the electrode. At 1.0 V/Ag|AgCl, jph is maximized and recombination is suppressed, which provides the conditions for efficient photoelectrochemical oxidation of MB. UVvis spectroscopy was used to evaluate the effect of the treatment and the results are presented in Figure 9c. The couple of
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Published 04 Oct 2018

Enhanced antineoplastic/therapeutic efficacy using 5-fluorouracil-loaded calcium phosphate nanoparticles

  • Shanid Mohiyuddin,
  • Saba Naqvi and
  • Gopinath Packirisamy

Beilstein J. Nanotechnol. 2018, 9, 2499–2515, doi:10.3762/bjnano.9.233

Graphical Abstract
  • synthesized CaP@5-FU NPs were characterized with UVvis spectroscopy over a range of 200 to 800 nm. The spectrum obtained displayed a characteristic peak at 230 nm [25] for unloaded CaP NPs and CaP@5-FU NPs as shown in Figure 1B. Also an absorption maximum was found at 265 nm for 5-FU, which was depressed in
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Published 20 Sep 2018

Nanoconjugates of a calixresorcinarene derivative with methoxy poly(ethylene glycol) fragments for drug encapsulation

  • Alina M. Ermakova,
  • Julia E. Morozova,
  • Yana V. Shalaeva,
  • Victor V. Syakaev,
  • Aidar T. Gubaidullin,
  • Alexandra D. Voloshina,
  • Vladimir V. Zobov,
  • Irek R. Nizameev,
  • Olga B. Bazanova,
  • Igor S. Antipin and
  • Alexander I. Konovalov

Beilstein J. Nanotechnol. 2018, 9, 2057–2070, doi:10.3762/bjnano.9.195

Graphical Abstract
  • macrocycle platform on substrate binding, 3 and mPEG-550 were compared regarding their influence on physico-chemical properties of the substrates by using UVvis spectroscopy and fluorimetry). The influence of substrate encapsulation on the size of micelles of 3 was determined by using DLS (Table S1
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Published 27 Jul 2018

Sulfur-, nitrogen- and platinum-doped titania thin films with high catalytic efficiency under visible-light illumination

  • Boštjan Žener,
  • Lev Matoh,
  • Giorgio Carraro,
  • Bojan Miljević and
  • Romana Cerc Korošec

Beilstein J. Nanotechnol. 2018, 9, 1629–1640, doi:10.3762/bjnano.9.155

Graphical Abstract
  • ), scanning electron microscopy (SEM), UVvis spectroscopy and band gap measurements. Results and Discussion Titania thin films were prepared by a particulate sol–gel synthesis, using titanium tetrachloride (TiCl4) as a precursor. During the synthesis, different quantities hydrochloric or sulfuric acid were
  •  7a) and synthesized with H2SO4 (Figure 7b). Different dots represent experimental data (acquired with UVvis spectroscopy) and lines represent a fitted kinetic model. A kinetic model for adsorption (zero-order rate constant, k0) and subsequent degradation (first-order rate constant, k1) was used to
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Published 04 Jun 2018

Closed polymer containers based on phenylboronic esters of resorcinarenes

  • Tatiana Yu. Sergeeva,
  • Rezeda K. Mukhitova,
  • Irek R. Nizameev,
  • Marsil K. Kadirov,
  • Polina D. Klypina,
  • Albina Y. Ziganshina and
  • Alexander I. Konovalov

Beilstein J. Nanotechnol. 2018, 9, 1594–1601, doi:10.3762/bjnano.9.151

Graphical Abstract
  • File 1, Figure S6). The weight of p(SRA-B) slowly decreases by 4% with the increase of temperature in the range of 250–375 °C. The p(SRA-B) dispersion is steady in water because of the negatively charged surface formed by sulfonated groups. The ζ-potential of p(SRA-B) is −50 mV. UVvis spectroscopy was
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Published 29 May 2018

Colorimetric detection of Cu2+ based on the formation of peptide–copper complexes on silver nanoparticle surfaces

  • Gajanan Sampatrao Ghodake,
  • Surendra Krishna Shinde,
  • Rijuta Ganesh Saratale,
  • Avinash Ashok Kadam,
  • Ganesh Dattatraya Saratale,
  • Asad Syed,
  • Fuad Ameen and
  • Dae-Young Kim

Beilstein J. Nanotechnol. 2018, 9, 1414–1422, doi:10.3762/bjnano.9.134

Graphical Abstract
  • stock AgNPs solution comprised 0.05, 0.1, and 0.2 mL, respectively, to enable detection over a wide range (0.08–1.44 µM Cu2+). After the coordination reaction was performed at 24 °C for 20 min, the spectral shift was detected by UVvis spectroscopy, and the solution color was observed with the naked eye
  • below the normal blood concentration of Cu2+, which is in the range of 24–135 µg/dL [27]. The interaction of Cu2+ with the peptide ligands on the AgNP surfaces attracts neighboring AgNPs, which is observed as a color change from yellow to red. The change in absorbance was monitored by UVvis
  • spectroscopy at various Cu2+ concentrations (0.08 to1.44 µM). The absorbance intensity at 520 nm increased with an increase of the Cu2+ concentration, and the sensitivity was purely dependent upon the volume of added AgNPs stock solution as presented in Figure 5. Thus, the quantitative features, including the
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Published 15 May 2018

Semi-automatic spray pyrolysis deposition of thin, transparent, titania films as blocking layers for dye-sensitized and perovskite solar cells

  • Hana Krýsová,
  • Josef Krýsa and
  • Ladislav Kavan

Beilstein J. Nanotechnol. 2018, 9, 1135–1145, doi:10.3762/bjnano.9.105

Graphical Abstract
  • microscopy (SEM) (Hitachi FE SEM S-4800 microscope), and UVvis spectroscopy (Varian CARY 100 with integrating sphere DRA-CA-30I and 8° reflectance geometry, Varian, USA). X-ray fluorescence spectroscopy (XRF) analysis was performed on an ARL 9400 XP sequential WD-XRF spectrometer (Thermo ARL, Switzerland
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Published 10 Apr 2018

Perovskite-structured CaTiO3 coupled with g-C3N4 as a heterojunction photocatalyst for organic pollutant degradation

  • Ashish Kumar,
  • Christian Schuerings,
  • Suneel Kumar,
  • Ajay Kumar and
  • Venkata Krishnan

Beilstein J. Nanotechnol. 2018, 9, 671–685, doi:10.3762/bjnano.9.62

Graphical Abstract
  • CTCN heterojunction and the corresponding control samples was investigated by studying the degradation of a model dye pollutant, rhodamine B (RhB) under UV, visible and natural sunlight irradiations. The prominent absorption peak of RhB at 554 nm was monitored by employing UVvis spectroscopy to
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Published 21 Feb 2018

Optimisation of purification techniques for the preparation of large-volume aqueous solar nanoparticle inks for organic photovoltaics

  • Furqan Almyahi,
  • Thomas R. Andersen,
  • Nathan A. Cooling,
  • Natalie P. Holmes,
  • Matthew J. Griffith,
  • Krishna Feron,
  • Xiaojing Zhou,
  • Warwick J. Belcher and
  • Paul C. Dastoor

Beilstein J. Nanotechnol. 2018, 9, 649–659, doi:10.3762/bjnano.9.60

Graphical Abstract
  • (DLS) (Zetasiser Nano-ZS ZEN3500, Malvern Instruments) with a 633 nm laser and a backscatter detector angle of 173°. Samples for DLS were prepared by diluting 5 µL of NP ink in 10 mL Milli-Q water in order to reduce the solids content from 6 to 0.003%. Free SDS concentration UV-vis spectroscopy: An
  • processes: centrifugal and crossflow ultrafiltration. The impact of purification is twofold: firstly, removal of excess sodium dodecyl sulfate (SDS) surfactant from the ink and, secondly, concentration of the photoactive components in the ink. The removal of SDS was studied in detail both by a UVvis
  • spectroscopy-based method and by surface tension measurements of the nanoparticle ink filtrate; revealing that centrifugal ultrafiltration removed SDS at a higher rate than crossflow ultrafiltration even though a similar filter was applied in both cases (10,000 Da Mw cut-off). The influence of SDS
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Published 20 Feb 2018

Fabrication and photoactivity of ionic liquid–TiO2 structures for efficient visible-light-induced photocatalytic decomposition of organic pollutants in aqueous phase

  • Anna Gołąbiewska,
  • Marta Paszkiewicz-Gawron,
  • Aleksandra Sadzińska,
  • Wojciech Lisowski,
  • Ewelina Grabowska,
  • Adriana Zaleska-Medynska and
  • Justyna Łuczak

Beilstein J. Nanotechnol. 2018, 9, 580–590, doi:10.3762/bjnano.9.54

Graphical Abstract
  • further growth and agglomeration. For the TiO2_O(1:3) sample, the dominant fraction were microspheres with diameter ranging from 2–3 μm (38%), whereas for TiO2_T(1:3), the main fraction was particles with an average diameter of 3–5 μm (42%). Diffuse reflectance spectroscopy, UVvis spectroscopy and BET
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Published 14 Feb 2018

Colloidal solution of silver nanoparticles for label-free colorimetric sensing of ammonia in aqueous solutions

  • Alessandro Buccolieri,
  • Antonio Serra,
  • Gabriele Giancane and
  • Daniela Manno

Beilstein J. Nanotechnol. 2018, 9, 499–507, doi:10.3762/bjnano.9.48

Graphical Abstract
  • vis spectroscopy; Introduction Important sources of ammonia include synthetic fertilizers, oceans, the burning of biomass, the decomposition of plants, natural land [1] and the chemical industry [2]. Ammonia is also an organic compound normally produced by human metabolism [3] through the urea cycle
  • been identified: very low ammonia concentrations from 0.01 to 0.2 ppm, high ammonia concentrations from 20 to 350 ppm and, most importantly, the intermediate or physiological range of ammonia from 0.5 to 10 ppm. Keywords: electron diffraction; electron microscopy; NH3 sensors; silver nanoparticles; UV
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Published 09 Feb 2018
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