Coating of upconversion nanoparticles with silica nanoshells of 5–250 nm thickness

• Cynthia Kembuan,
• Maysoon Saleh,
• Bastian Rühle,
• Ute Resch-Genger and
• Christina Graf

Beilstein J. Nanotechnol. 2019, 10, 2410–2421, doi:10.3762/bjnano.10.231

• microemulsion technique in 2008 [42][43]. However, for certain applications such as sensing and plasmonics, a thicker silica shell is desired that can be loaded with sensor molecules or used as spacer for the plasmonic enhancement of the emission of UCNPs by gold or silver shells [45]. Moreover, since UCNPs can

The role of Ag⁺, Ca²⁺, Pb²⁺ and Al³⁺ adions in the SERS turn-on effect of anionic analytes

• Stefania D. Iancu,
• Andrei Stefancu,
• Vlad Moisoiu,
• Loredana F. Leopold and
• Nicolae Leopold

Beilstein J. Nanotechnol. 2019, 10, 2338–2345, doi:10.3762/bjnano.10.224

• adsorption sites specific for the anionic analytes. The turn-on of the SERS effect is explained in the context of the chemical mechanism of SERS. The adions form SERS-active sites on the silver surface enabling a charge transfer between the adsorbate and the silver surface. High-intensity SERS spectra of

• uric acid, salicylic acid and fumaric acid could be recorded at a concentration of 50 µM only after activation of the colloidal silver nanoparticles by Ca2+, Pb2+ or Al3+ (50 µM). The chemisorption of the three anionic species to the silver surface occurs competitively and is enhanced with the anions

• of higher affinities to the silver surface as indicated by the SERS spectra of corresponding mixed solutions. Keywords: adion-specific adsorption model; cation bridging; Raman; surface enhanced Raman scattering (SERS); Introduction Surface-enhanced Raman scattering (SERS) is an ultrasensitive

Use of data processing for rapid detection of the prostate-specific antigen biomarker using immunomagnetic sandwich-type sensors

• Camila A. Proença,
• Tayane A. Freitas,
• Thaísa A. Baldo,
• Elsa M. Materón,
• Flávio M. Shimizu,
• Gabriella R. Ferreira,
• Frederico L. F. Soares,
• Ronaldo C. Faria and
• Osvaldo N. Oliveira Jr.

Beilstein J. Nanotechnol. 2019, 10, 2171–2181, doi:10.3762/bjnano.10.210

• anti-PSA antibodies were obtained from Abcam, Cambridge, UK. Graphite-based ink was obtained from Henkel Electrodag, USA (reference code 423SS), silver chloride ink was purchased from Gwent electronic materials Ltd., UK (Product code C2130905D3), the cell lines PNT-2 and LNCap were acquired from the

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

• describes the preparation and characterization of a new type of core–shell nanoparticle in which the structure consists of a hydrogel core encapsulated within a porous silver shell. The thermo-responsive hydrogel cores were prepared by surfactant-free emulsion polymerization of a selected mixture of N

• -isopropylacrylamide (NIPAM) and acrylic acid (AAc). The hydrogel cores were then encased within either a porous or complete silver shell for which the localized surface plasmon resonance (LSPR) extends from visible to near-infrared (NIR) wavelengths (i.e., λmax varies from 550 to 1050 nm, depending on the porosity

• ), allowing for reversible contraction and swelling of the hydrogel via photothermal heating of the surrounding silver shell. Given that NIR light can pass through tissue, and the silver shell is porous, this system can serve as a platform for the smart delivery of payloads stored within the hydrogel core

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

• ]. Electrical measurements: Pressed pellets (F ≈ 5 US tons) were cut in rectangular shapes and contacted with silver conductive paint (RS 123-9911) and platinum wires (Goodfellow, 99.99%, 25 μm of diameter) in a four-probe configuration (Figure S2 and Figure S3, Supporting Information File 1). The geometrical

Toxicity and safety study of silver and gold nanoparticles functionalized with cysteine and glutathione

• Barbara Pem,
• Igor M. Pongrac,
• Lea Ulm,
• Ivan Pavičić,
• Valerije Vrček,
• Darija Domazet Jurašin,
• Marija Ljubojević,
• Adela Krivohlavek and
• Ivana Vinković Vrček

Beilstein J. Nanotechnol. 2019, 10, 1802–1817, doi:10.3762/bjnano.10.175

• Zagreb, Croatia 10.3762/bjnano.10.175 Abstract This study was designed to evaluate the nano–bio interactions between endogenous biothiols (cysteine and glutathione) with biomedically relevant, metallic nanoparticles (silver nanoparticles (AgNPs) and gold nanoparticles (AuNPs)), in order to assess the

• . Keywords: biocompatibility; cysteine; ecotoxicity; glutathione; nano–bio interactions; nanosafety; nanotoxicity; Introduction Metallic nanoparticles (NPs) such as silver and gold have been employed in a wide range of products and applications in the biomedical field owing to their remarkable physico

• -chemical properties. Silver nanoparticles (AgNPs) are extensively used in antimicrobial coatings for medical devices, wound dressing, cosmetic products and food packaging due to their antimicrobial, antiangiogenic and anti-inflammatory properties [1][2][3][4][5]. Biomedical applications of gold

Synthesis of nickel/gallium nanoalloys using a dual-source approach in 1-alkyl-3-methylimidazole ionic liquids

• Ilka Simon,
• Julius Hornung,
• Juri Barthel,
• Jörg Thomas,
• Maik Finze,
• Roland A. Fischer and
• Christoph Janiak

Beilstein J. Nanotechnol. 2019, 10, 1754–1767, doi:10.3762/bjnano.10.171

• samples of copper, silver and gold at 50 eV and 10 eV pass energy and comparison with reference values. Spectra were obtained with an Al Kα X-ray source, using C 1s as a reference for the binding energy [50]. Gas chromatography–mass spectrometry (GC–MS) data were recorded on a Thermo Finnigan Trace DSQ

Novel hollow titanium dioxide nanospheres with antimicrobial activity against resistant bacteria

• Carol López de Dicastillo,
• Cristian Patiño,
• María José Galotto,
• Yesseny Vásquez-Martínez,
• Claudia Torrent,
• Daniela Alburquenque,
• Alejandro Pereira and
• Juan Escrig

Beilstein J. Nanotechnol. 2019, 10, 1716–1725, doi:10.3762/bjnano.10.167

• -positive and Gram-negative bacteria [2]. In recent years, metal and metal oxide NPs, such as silver, gold, titanium and zinc oxide NPs, have been extensively studied due to their interesting antimicrobial character [3][4][5]. Titanium dioxide (TiO2) NPs have also attracted significant attention due to

Materials nanoarchitectonics at two-dimensional liquid interfaces

• Katsuhiko Ariga,
• Michio Matsumoto,
• Taizo Mori and
• Lok Kumar Shrestha

Beilstein J. Nanotechnol. 2019, 10, 1559–1587, doi:10.3762/bjnano.10.153

• ) [252]. Three-dimensional cubic structures were precipitated as Olmstead’s crystalline C60–Ag(I) organometallic hetero-nanostructures [C60{AgNO3}5] at the interface between a saturated benzene solution of C60 and an ethanol solution of silver(I) nitrate. The formed cubic structures underwent structural

Superconducting switching due to a triplet component in the Pb/Cu/Ni/Cu/Co₂Cr_1−xFe_xAl_y spin-valve structure

• Andrey Andreevich Kamashev,
• Nadir Nurgayazovich Garif’yanov,
• Aidar Azatovich Validov,
• Joachim Schumann,
• Vladislav Kataev,
• Bernd Büchner,
• Yakov Victorovich Fominov and
• Ilgiz Abdulsamatovich Garifullin

Beilstein J. Nanotechnol. 2019, 10, 1458–1463, doi:10.3762/bjnano.10.144

• mechanically removed from the areas where the golden wires should be attached using a silver paste. The quality of the Pb layer can be judged from the residual resistivity ratio (RRR): Here, R(T) is the measured resistance at a given temperature T, ρph(300 K) is the phonon contribution to the specific

A silver-nanoparticle/cellulose-nanofiber composite as a highly effective substrate for surface-enhanced Raman spectroscopy

• Yongxin Lu,
• Yan Luo,
• Zehao Lin and
• Jianguo Huang

Beilstein J. Nanotechnol. 2019, 10, 1270–1279, doi:10.3762/bjnano.10.126

• Raman scattering (SERS) substrate was developed by facile deposition of silver nanoparticles onto cellulose fibers of ordinary laboratory filter paper. This was achieved by means of the silver mirror reaction in a manner to control both the size of the silver nanoparticles and the silver density of the

• substrate. This paper-based substrate is composed of a particle-on-fiber structure with the unique three-dimensional network morphology of the cellulose matrix. For such a SERS substrate with optimized size of the silver nanoparticles (ca. 70 nm) and loading density of silver (17.28 wt %), a remarkable

• . This low-cost, highly sensitive, and biocompatible paper-based SERS substrate holds considerable potentials for the detection and analyses of chemical and biomolecular species. Keywords: cellulose nanofiber; composites; nanoarchitectonics; silver nanoparticle; surface-enhanced Raman spectroscopy

Photoactive nanoarchitectures based on clays incorporating TiO₂ and ZnO nanoparticles

• Eduardo Ruiz-Hitzky,
• Pilar Aranda,
• Marwa Akkari,
• Nithima Khaorapapong and
• Makoto Ogawa

Beilstein J. Nanotechnol. 2019, 10, 1140–1156, doi:10.3762/bjnano.10.114

• doping. Silver metal NPs (Ag) were prepared from AgNO3 and deposited over ZnO@montmorillonite following a green approach for the Ag+ reduction. Here again, the doped nanoarchitecture (Ag–ZnO@montmorillonite) exhibited a better efficiency than the corresponding ZnO@montmorillonite and Ag@ZnO samples, in

Scavenging of reactive oxygen species by phenolic compound-modified maghemite nanoparticles

• Małgorzata Świętek,
• Yi-Chin Lu,
• Rafał Konefał,
• Liliana P. Ferreira,
• M. Margarida Cruz,
• Yunn-Hwa Ma and
• Daniel Horák

Beilstein J. Nanotechnol. 2019, 10, 1073–1088, doi:10.3762/bjnano.10.108

• , phenolic compounds with a higher number of hydroxy groups have enhanced ROS scavenging capability. In addition to low-molecular-weight phenolic compounds of natural origin, some inorganic nanoparticles also have antioxidant properties, e.g., zinc, cerium, magnesium oxide, magnetite, and silver [6][7][8][9

Revisiting semicontinuous silver films as surface-enhanced Raman spectroscopy substrates

• Malwina Liszewska,
• Bogusław Budner,
• Małgorzata Norek,
• Bartłomiej J. Jankiewicz and
• Piotr Nyga

Beilstein J. Nanotechnol. 2019, 10, 1048–1055, doi:10.3762/bjnano.10.105

• nanostructures fabricated using physical methods, such as semicontinuous metal films obtained via electron beam physical vapor deposition. In these studies, we investigate the influence of morphology of semicontinuous silver films on their SERS properties. The morphologies studied ranged from isolated particles

• through percolated films to almost continuous films. We found that films below the percolation threshold (transition from dielectric-like to metal-like) made of isolated silver structures provided the largest SERS enhancement of 4-aminothiophenol (4-ATP) analyte signals. The substrate closest to the

• percolation threshold has the SERS signal about four times lower than the highest signal sample. Keywords: metal island film; plasmon resonance; semicontinuous silver film; SERS; surface-enhanced Raman spectroscopy; Introduction Noble metal nanostructures exhibit exceptional optical properties. They can

Enhanced inhibition of influenza virus infection by peptide–noble-metal nanoparticle conjugates

• Zaid K. Alghrair,
• David G. Fernig and
• Bahram Ebrahimi

Beilstein J. Nanotechnol. 2019, 10, 1038–1047, doi:10.3762/bjnano.10.104

• a mixed-matrix ligand shell of a peptidol and an alkanethiol ethylene glycol consisting of 70% CVVVTol and 30% HS(CH2)11(OC2H4)4OH (mol/mol). Gold and silver nanoparticles (ca. 10 nm diameter) with up to 5% (mol/mol) FluPep ligand remained as stable as the control of mixed-matrix-passivated

• demonstrate that conjugation of FluPep to gold and silver nanoparticles enhances its antiviral potency; the antimicrobial activity of silver ions may enable the design of even more potent antimicrobial inhibitors, capable of targeting both influenza and bacterial co-infections. Keywords: antiviral peptides

• ; gold nanoparticles; influenza virus; lytic infection; silver nanoparticles; Introduction The influenza (“flu”) type-A virus is a major health concern for humans and livestock animals. The primary mode of transmission is by the respiratory route. Flu infection occurs seasonally and can cause global

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

• and characterization of silver nanoisland films (SNIFs) using pulsed laser deposition (PLD) and the evaluation of these films as potential surface-enhanced Raman scattering (SERS) substrates are reported. The SNIFs with thicknesses in a range of 4.7 ± 0.2 nm to 143.2 ± 0.2 nm were deposited under

• different conditions on silicon substrates. Size and morphology of the fabricated silver nanoislands mainly depend on the substrate temperature, and number and energy of the laser pulses. SERS properties of the fabricated films were evaluated by measuring SERS spectra of para-mercaptoaniline (pMA) molecules

• adsorbed on them. SERS enhancement factors are shown to depend on the SNIF morphology, which is modified by changes of the deposition conditions. The highest enhancement factor in the range of 105 was achieved for SNIFs that have oval and circular silver nanoislands with small distances between them

Polydopamine-coated Au nanorods for targeted fluorescent cell imaging and photothermal therapy

• Boris N. Khlebtsov,
• Andrey M. Burov,
• Timofey E. Pylaev and
• Nikolai G. Khlebtsov

Beilstein J. Nanotechnol. 2019, 10, 794–803, doi:10.3762/bjnano.10.79

• tetrachloroaurate trihydrate (HAuCl4·3H2O) and silver nitrate (AgNO3, >99%) were purchased from Alfa Aesar. Ultrapure water obtained from a Milli-Q Integral 5 system was used in all experiments. Synthesis of AuNRs AuNRs with a plasmon peak at around 800 nm were obtained by the seed-mediated growth method [41

On the transformation of “zincone”-like into porous ZnO thin films from sub-saturated plasma enhanced atomic layer deposition

• Alberto Perrotta,
• Julian Pilz,
• Stefan Pachmajer,
• Antonella Milella and
• Anna Maria Coclite

Beilstein J. Nanotechnol. 2019, 10, 746–759, doi:10.3762/bjnano.10.74

• , respectively. Under the set conditions, the energy resolution of the analyzer (FWHM, full width at half-maximum height), measured on the silver Ag 3d5/2 photoemission line, was 0.7 eV for a pass energy of 29.35 eV. All spectra were acquired at a take-off angle of 45° with respect to the sample surface. Surface

Deposition of metal particles onto semiconductor nanorods using an ionic liquid

• Michael D. Ballentine,
• Elizabeth G. Embry,
• Marco A. Garcia and
• Lawrence J. Hill

Beilstein J. Nanotechnol. 2019, 10, 718–724, doi:10.3762/bjnano.10.71

• an ionic liquid, and the effect this has on catalytic performance. Platinum, gold, and silver nanoparticles were deposited onto CdSe@CdS (core@shell) nanorods from metal salts in an ionic liquid (1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) without additional surfactants or reducing

• methylene blue. This hybrid approach using traditional organic ligands for the synthesis of well-defined nanorods followed by [bmim][Tf2N] for metal deposition was found to be applicable to other noble metals in addition to platinum. Gold and silver nanoparticles were also deposited onto CdSe@CdS nanorods

• tol-NR), both materials may react at similar rates with the solvent to neutralize accumulated positive charges in the catalyst. We then investigated reduction of gold and silver in the presence of CdSe@CdS nanorods using [bmim][Tf2N] without any additional surfactants or reducing agents to determine

The effect of translation on the binding energy for transition-metal porphyrines adsorbed on Ag(111) surface

• Luiza Buimaga-Iarinca and
• Cristian Morari

Beilstein J. Nanotechnol. 2019, 10, 706–717, doi:10.3762/bjnano.10.70

• atom on top the surface. We show that the interaction between the transition metal and silver is the result of a combination between the dispersion interaction, charge transfer and weak chemical interaction. The detailed analysis of the physical properties, such as dipolar and magnetic moments and the

• . Such modifications of the electronic structure are of great interest for all potential applications. Theoretical assessment of the adsorption mechanism of TMPP on silver in the framework of DFT ask for an accurate estimation of the van der Waals dispersive interactions, which are expected to be

• dependence of physical parameters such as binding energy, dipolar moment and charge transfer on the transition-metak atom in the TMPP as well as on the position of the molecule on top of the silver surface. These data will provide a base for deeper understanding of the self-assembly processes involving TMPP

Self-assembly and wetting properties of gold nanorod–CTAB molecules on HOPG

• Imtiaz Ahmad,
• Floor Derkink,
• Tim Boulogne,
• Pantelis Bampoulis,
• Harold J. W. Zandvliet,
• Hidayat Ullah Khan,
• Rahim Jan and
• E. Stefan Kooij

Beilstein J. Nanotechnol. 2019, 10, 696–705, doi:10.3762/bjnano.10.69

• conceptual framework used in this work are similar to our work presented elsewhere [9][51]. Materials Hydrogen tetrachloroaurate (HAuCl4·3H2O, 99.999%, Aldrich), silver nitrate (AgNO3, 99%, Acros), ascorbic acid (AA, 99%, Merck), cetyltrimethylammonium bromide (CTAB, Aldrich, 98%), sodium borohydrate (NaBH4

Ultrathin hydrophobic films based on the metal organic framework UiO-66-COOH(Zr)

• Miguel A. Andrés,
• Clemence Sicard,
• Christian Serre,
• Olivier Roubeau and
• Ignacio Gascón

Beilstein J. Nanotechnol. 2019, 10, 654–665, doi:10.3762/bjnano.10.65

• determined. This value is in good agreement with the thickness previously reported for ODP monolayers deposited onto silver or gold substrates [33] and reveals that molecules in the film adopt an almost vertical position. Moreover, some domains of different sizes and heights up to 25 nm can be observed

Enhancement in thermoelectric properties due to Ag nanoparticles incorporated in Bi₂Te₃ matrix

• Srashti Gupta,
• Dinesh Chandra Agarwal,
• Bathula Sivaiah,
• Sankarakumar Amrithpandian,
• Kandasami Asokan,
• Ajay Dhar,
• Binaya Kumar Panigrahi,
• Devesh Kumar Avasthi and
• Vinay Gupta

Beilstein J. Nanotechnol. 2019, 10, 634–643, doi:10.3762/bjnano.10.63

• silver (Ag) nano-inclusions (0, 2, 5, 10, 15 and 20 wt %). Transmission electron microscopy (TEM) images of Ag incorporated in Bi2Te3 annealed at 573 K shows tubular, pentagonal, trigonal, circular and hexagonal nanoparticles with sizes of 6–25 nm (for 5 wt % Ag ) and 7–30 nm (for 20 wt % Ag). Ag

• at different temperatures (573 and 773 K). Experimental Bismuth telluride (Bi2Te3) powder was purchased from Alfa Aesar (99.99% purity). Silver (Ag) powder (7–15 µm particles) was purchased from Ted Pella Inc. Different fractions (0, 2, 5, 10, 15 and 20 wt %) of Ag powder were added to Bi2Te3. The

Biomimetic synthesis of Ag-coated glasswing butterfly arrays as ultra-sensitive SERS substrates for efficient trace detection of pesticides

• Guochao Shi,
• Mingli Wang,
• Yanying Zhu,
• Yuhong Wang,
• Xiaoya Yan,
• Xin Sun,
• Haijun Xu and
• Wanli Ma

Beilstein J. Nanotechnol. 2019, 10, 578–588, doi:10.3762/bjnano.10.59

• Scientific Ltd. (Beijing, China). The silver target (diameter: 50.8 mm, thickness: 3.175 mm, purity: 99.99%) was obtained from China Material Technology Co., Ltd. (Jiangxi, China). All the chemicals were used without further purification. Deionized water (18.25 MΩ·cm) was used throughout all the experiments

Quantification and coupling of the electromagnetic and chemical contributions in surface-enhanced Raman scattering

• Yarong Su,
• Yuanzhen Shi,
• Ping Wang,
• Jinglei Du,
• Markus B. Raschke and
• Lin Pang

Beilstein J. Nanotechnol. 2019, 10, 549–556, doi:10.3762/bjnano.10.56

• relative contributions nor the substrate dependence of the chemical effect have been well established. Moreover, there is to date no understanding of a possible coupling between both effects. Here we demonstrate how systematically engineered silver and gold planar and nanostructured substrates, covering a

• ]. Only the ω3 mode is thought to be sensitive to charge redistribution due to the nuclear motion of the S-atom with respect to metal substrate and phenyl ring [15]. DFT calculations (Gaussian 09 package) were performed based on benzenethiol bound to three silver atom clusters, for illustration, and the