Functionalized platinum nanoparticles with surface charge trigged by pH: synthesis, characterization and stability studies

• Giovanna Testa,
• Laura Fontana,
• Iole Venditti and
• Ilaria Fratoddi

Beilstein J. Nanotechnol. 2016, 7, 1822–1828, doi:10.3762/bjnano.7.175

• , such as an organic thiol, is present in solution, it gives rise to a passivation layer that hinders the coalescence and precipitation, allowing the colloidal suspension to remain stable [22]. Among reducing agents, hydrazine and sodium borohydride are the most commonly used but also natural-origin

3D printing of mineral–polymer bone substitutes based on sodium alginate and calcium phosphate

• Aleksey A. Egorov,
• Alexander Yu. Fedotov,
• Anton V. Mironov,
• Vladimir S. Komlev,
• Vladimir K. Popov and
• Yury V. Zobkov

Beilstein J. Nanotechnol. 2016, 7, 1794–1799, doi:10.3762/bjnano.7.172

• biomimetic approach in which 3D printing of composite structures involves a chemical interaction of the polymer slurry with a liquid “ink”, leading to in situ formation of a CP phase in the final product. It is well known that alginate allows precipitation of inorganic phases within its macromolecular

• glutamic acids in the reaction medium maintained at pH 4.5 ± 0.5 yields the formation of dicalcium phosphate dihydrate (DCPD) in the printed samples (Figure 2). When precipitation is performed at a higher pH, as reported in [7][14], the difference of electrical charges in alginate is greater. As a

Influence of hydrothermal synthesis parameters on the properties of hydroxyapatite nanoparticles

• Sylwia Kuśnieruk,
• Jacek Wojnarowicz,
• Agnieszka Chodara,
• Tadeusz Chudoba,
• Stanislaw Gierlotka and
• Witold Lojkowski

Beilstein J. Nanotechnol. 2016, 7, 1586–1601, doi:10.3762/bjnano.7.153

• Hydroxyapatite (HAp) nanoparticles of tunable diameter were obtained by the precipitation method at room temperature and by microwave hydrothermal synthesis (MHS). The following parameters of the obtained nanostructured HAp were determined: pycnometric density, specific surface area, phase purity, lattice

• chemistry techniques, such as direct precipitation from aqueous solutions, electrochemical deposition [23], sol–gel processes [24] and hydrothermal synthesis [25][26][27] (Table 1). In the majority of cases, the synthesized powder is a stoichiometric hydroxyapatite, and oftentimes contains additional phases

• precise control of the average particle size and particle size distribution can be maintained and these parameters can still be precisely tuned. Experimental Materials The HAp nanopowder was synthesized via a simple precipitation method (exactly in the acid/base neutralization process). The precursors for

An ellipsometric approach towards the description of inhomogeneous polymer-based Langmuir layers

• Falko O. Rottke,
• Burkhard Schulz,
• Klaus Richau,
• Karl Kratz and
• Andreas Lendlein

Beilstein J. Nanotechnol. 2016, 7, 1156–1165, doi:10.3762/bjnano.7.107

• observed by BAM and IE (Figure 2a). The short time elapsed between the spreading procedure and the observation of morphologies leads to the assumption that they are generated by precipitation-like processes. During compression, the free areas in between the morphologies are reduced, causing just a small

• . Regarding Figure 5b, the height gap between the slab and monolayer is around 4 nm in the dewetted state. This clearly supports the results provided by the complementary use of spectroscopic ellipsometry and nulling-based thickness mapping. Hence the low lateral movement and precipitation-caused structures

Multiwalled carbon nanotube hybrids as MRI contrast agents

• Nikodem Kuźnik and
• Mateusz M. Tomczyk

Beilstein J. Nanotechnol. 2016, 7, 1086–1103, doi:10.3762/bjnano.7.102

• with europium, gadolinium and lanthanum fluoride co-precipitation (EuGdLa/SiO2/PAH/MWCNT#Chen) [25]. The authors claimed that fluoride nanocrystals (5–10 nm) coated the MWCNT effectively due to high electrostatic attraction from the polyelectrolyte. The silica layer was introduced to prevent

• (SPIO/oMWCNT#Wu) [38], while Wang used the thermal annealing method of iron(II) acetate (SPIO/oMWCNT#Wang) [43]. Solvothermal co-precipitation of CoCl2 and FeCl3, also by Wu, led to the non-covalent deposition of magnetic cobalt ferrite (CoFe2O4/oMWCNT#Wu) [39]. It was found that a low temperature (180

• from the in situ precipitation of SiO2 on PAH non-covalently coated oMWCNT followed by co-precipitation of lanthanide fluorides [25]. In Liu’s work, the sonication product of oMWCNT with poly(diallyldimethylammonium chloride) (PDDA) was used to anchor SPIO@Lac-Gly yielding SPIO@Lac-Gly/PDDA/oMWCNT#Liu

Reconstitution of the membrane protein OmpF into biomimetic block copolymer–phospholipid hybrid membranes

• Matthias Bieligmeyer,
• Franjo Artukovic,
• Stephan Nussberger,
• Thomas Hirth,
• Thomas Schiestel and
• Michaela Müller

Beilstein J. Nanotechnol. 2016, 7, 881–892, doi:10.3762/bjnano.7.80

• polymerization, the block copolymer is isolated by precipitation in cold ethanol, decanted, then re-dissolved in chloroform, filtrated and dried in vacuum. PIPEOs are stored at −20 °C under an Ar atmosphere. Polymer analysis Size-exclusion chromatography SEC was performed on a SECcurity System (PSS GmbH, Mainz

Selective photocatalytic reduction of CO₂ to methanol in CuO-loaded NaTaO₃ nanocubes in isopropanol

• Tianyu Xiang,
• Feng Xin,
• Jingshuai Chen,
• Yuwen Wang,
• Xiaohong Yin and
• Xiao Shao

Beilstein J. Nanotechnol. 2016, 7, 776–783, doi:10.3762/bjnano.7.69

• –precipitation mechanism, where the concentration of the NaOH solution played a crucial role on the morphology of the crystal. This was confirmed in our work. Figure 3 shows UV–vis diffuse reflectance spectra and optical absorption edges of NaTaO3 nanocubes prepared with different concentrations of NaOH. From

Microwave solvothermal synthesis and characterization of manganese-doped ZnO nanoparticles

• Jacek Wojnarowicz,
• Roman Mukhovskyi,
• Elzbieta Pietrzykowska,
• Sylwia Kusnieruk,
• Jan Mizeracki and
• Witold Lojkowski

Beilstein J. Nanotechnol. 2016, 7, 721–732, doi:10.3762/bjnano.7.64

• ., formation of clusters [31]), the precipitation of foreign phases [33][34], the stoichiometry; the presence of oxygen vacancies [35][36], and defects of the crystalline lattice. When the synthesis or calcination of Zn1−xMnxO was carried out in an oxidising environment and the absence of foreign phases was

• selected an organic solvent with weak reducing properties to prevent the precipitation of foreign phases, which is caused above all by the changed oxidisation state of Mn2+ ions. The microwave solvothermal synthesis was selected for obtaining Zn1−xMnxO. It was shown before by us that the MSS method led to

Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform

• M. Fátima Barroso,
• M. Alejandra Luna,
• Juan S. Flores Tabares,
• Cristina Delerue-Matos,
• N. Mariano Correa,
• Fernando Moyano and
• Patricia G. Molina

Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58

• decorate vesicles that could be used as a model system to illustrate controlled delivery of molecules under mild hyperthermia. These systems were prepared by using cetyltrimethylammonium chloride and myristic acid, and the nanomaterial was synthetized in aqueous alkaline solution by a co-precipitation

Fabrication and properties of luminescence polymer composites with erbium/ytterbium oxides and gold nanoparticles

• Julia A. Burunkova,
• Ihor Yu. Denisiuk,
• Dmitri I. Zhuk,
• Lajos Daroczi,
• Attila Csik,
• István Csarnovics and
• Sándor Kokenyesi

Beilstein J. Nanotechnol. 2016, 7, 630–636, doi:10.3762/bjnano.7.55

• , which makes them unusable for photonics. Other methods also have shortcomings. For example, the synthesis of Er2O3 nanoparticles through the co-precipitation method with addition of coordinating ligands needs additional co-precipitants, and still high temperature annealing is necessary [4]. This method

Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures

• Tuan Anh Pham,
• Andreas Schreiber,
• Elena V. Sturm (née Rosseeva),
• Stefan Schiller and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32

• only takes place for the Hcp1_cys3-functionalized NPs, where the citrate-stabilized Au NPs remain stable as evidenced by their unchanged surface plasmon resonance at 520 nm. When the NaCl concentration exceeded 12 mM, a prompt color change to blue followed by precipitation of a blue solid was observed

• elongation of the NPs assembly structures. The decrease in the absorbance between 17 h and 22 h is due to the slight precipitation of large Au Hcp1_cys3 structures. For better visualization of the different Au NP architectures, a cryo-TEM investigation was conducted for 3 samples at 7.5 h, 17 h and 22 h, as

• NPs were synthesized by the reported protocols of Slot [42] and Cabrera [36], respectively. All NPs systems were dispersible in water. The ligand exchange for CoFe2O4 NP was conducted by the modified protocol of Lees [41]. In the modified protocol, the precipitation with hexane/ethanol was replaced by

Hydration of magnesia cubes: a helium ion microscopy study

• Ruth Schwaiger,
• Johannes Schneider,
• Gilles R. Bourret and
• Oliver Diwald

Beilstein J. Nanotechnol. 2016, 7, 302–309, doi:10.3762/bjnano.7.28

• H2O depending on their size and distribution at the sample surface. Comparison between (a) and (b) points to the volume expansion during hydration and hydroxylation, while (c) and (d) show a probable dissolution/precipitation mechanism. (HIM SE images recorded at 30 kV acceleration voltage and (a,c

Surface coating affects behavior of metallic nanoparticles in a biological environment

• Darija Domazet Jurašin,
• Marija Ćurlin,
• Ivona Capjak,
• Tea Crnković,
• Marija Lovrić,
• Michal Babič,
• Daniel Horák,
• Ivana Vinković Vrček and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 246–262, doi:10.3762/bjnano.7.23

• ) was added to an aqueous solution of AgNO3 and BSA under vigorous stirring. The molar ratio of Ag+:BSA and were 28:1 and 1:1, respectively. The reaction volume was 40 mL, and contained 13.50 μmol BSA. The reaction was allowed to proceed for 1 h, and the product was purified by precipitation at −5 °C

Characterisation of thin films of graphene–surfactant composites produced through a novel semi-automated method

• Nik J. Walch,
• Alexei Nabok,
• Frank Davis and
• Séamus P. J. Higson

Beilstein J. Nanotechnol. 2016, 7, 209–219, doi:10.3762/bjnano.7.19

• peristaltic pump (B). The reservoir containing the surfactant and the tubing carrying it to the reactor are heated to 50 °C in a water bath (C) to prevent precipitation of the surfactant from solution in the tubing. A water trough (F) is used as a heat sink to dissipate any heat produced in the reactor during

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

• reaction at 4 °C with T4 DNA ligase (Roche, Lifescience, Switzerland). Excess oligonucleotides were cleaned off by ethanol precipitation using sodium acetate as counter ions. Modified λ-DNA was resuspended in 10 mM HEPES, 1 mM EDTA buffer, pH 7.2. The biotinylated end was modified with a 100× concentration

Simultaneous cancer control and diagnosis with magnetic nanohybrid materials

• Reza Saadat and
• Franz Renz

Beilstein J. Nanotechnol. 2016, 7, 121–125, doi:10.3762/bjnano.7.14

• through the well-established co-precipitation method [15] and proceeded with further functionalization to obtain biocompatible particles that can assemble and disassemble by entering media with different pH values. The resulting cave structure consists of three nanoparticle units in every spatial

Chemical bath deposition of textured and compact zinc oxide thin films on vinyl-terminated polystyrene brushes

• Nina J. Blumenstein,
• Caroline G. Hofmeister,
• Peter Lindemann,
• Cheng Huang,
• Johannes Baier,
• Andreas Leineweber,
• Stefan Walheim,
• Christof Wöll,
• Thomas Schimmel and
• Joachim Bill

Beilstein J. Nanotechnol. 2016, 7, 102–110, doi:10.3762/bjnano.7.12

• [36] as organic templates are known, which can modify the surface charge on the substrates for ZnO precipitation under moderate conditions. Based on these studies, we investigated the ZnO film formation on silicon wafers modified with vinyl-terminated polystyrene (PS) brushes. Those brushes consist of

• results imply an activated dynamic precipitation model of ZnO thin films, which is the result of a base-catalyzed transesterification of polystyrene brushes in the early stage of ZnO precipitation. Results and Discussion Template characterization For the deposition of the PS brush, the molecule depicted

pH-Triggered release from surface-modified poly(lactic-co-glycolic acid) nanoparticles

• Manuel Häuser,
• Klaus Langer and
• Monika Schönhoff

Beilstein J. Nanotechnol. 2015, 6, 2504–2512, doi:10.3762/bjnano.6.260

• final nanoparticle precipitation. After particle formation, the dispersion was washed by centrifugation (Centrifuge 5242, Eppendorf, Germany) and removal of the supernatant containing excess PVA. The procedure was followed by redispersion in ultrapure water, treatment by a vortexing device (VWR VV3

Influence of wide band gap oxide substrates on the photoelectrochemical properties and structural disorder of CdS nanoparticles grown by the successive ionic layer adsorption and reaction (SILAR) method

• Mikalai V. Malashchonak,
• Alexander V. Mazanik,
• Olga V. Korolik,
• Еugene А. Streltsov and
• Anatoly I. Kulak

Beilstein J. Nanotechnol. 2015, 6, 2252–2262, doi:10.3762/bjnano.6.231

• carried out by potentiostatic cathodic polarization of FTO electrodes at −1000 mV vs Ag/AgCl/KCl (sat.) reference electrode (+0.201 V vs SHE) for 25 min. Because of the formation of hydroxyl ions, a local increase of рН occurs, and the hydrolysis of Zn2+ ions is promoted and precipitation of Zn5(OH)8Cl2

Paramagnetism of cobalt-doped ZnO nanoparticles obtained by microwave solvothermal synthesis

• Jacek Wojnarowicz,
• Sylwia Kusnieruk,
• Tadeusz Chudoba,
• Stanislaw Gierlotka,
• Witold Lojkowski,
• Wojciech Knoff,
• Malgorzata I. Lukasiewicz,
• Bartlomiej S. Witkowski,
• Anna Wolska,
• Marcin T. Klepka,
• Tomasz Story and
• Marek Godlewski

Beilstein J. Nanotechnol. 2015, 6, 1957–1969, doi:10.3762/bjnano.6.200

• nitrogen, the precipitation of metallic α-Co was detected for a Co content of 5 mol % or more. For samples annealed in synthetic air, no change of phase structure was detected, except for precipitation of Co3O4 for a Co content of 15 mol %. The results of the magentometry investigation indicated that all

• , likely related to the precipitation of metallic Co in nanoparticles. Keywords: cobalt-doped zinc oxide; ferromagnetism; magnetic properties; microwave solvothermal synthesis (MSS); paramagnetism; Introduction Nanomaterials have drawn the attention of researchers from all over the world due to their new

• )2 were not detected. As confirmed in Figure 7, annealing at 800 °C in nitrogen atmosphere results in the visible precipitation of metallic α-cobalt for the samples with more than 1 mol % Co ion content [72]. When annealed in synthetic air, some precipitation of Co3O4 was observed in the XRD

Temperature-dependent breakdown of hydrogen peroxide-treated ZnO and TiO₂ nanoparticle agglomerates

• Sinan Sabuncu and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 1897–1903, doi:10.3762/bjnano.6.193

• the change in the size of untreated and hydroxylated ZnO NPs at each temperature interval. Due to the very low dispersion of untreated ZnO NPs in dH2O, the size variation is very high. The uncontrolled precipitation of untreated ZnO NPs leads to the irregular size change with increasing temperature

NanoE-Tox: New and in-depth database concerning ecotoxicity of nanomaterials

• Katre Juganson,
• Angela Ivask,
• Irina Blinova,
• Monika Mortimer and
• Anne Kahru

Beilstein J. Nanotechnol. 2015, 6, 1788–1804, doi:10.3762/bjnano.6.183

• on their fate in respective conditions [24][49]. In aquatic environment, ENMs tend to form agglomerates that might lead to their precipitation from the water phase; on the other hand, metal-based ENMs can release potentially toxic metal ions due to dissolution [50]. Cu2+, Zn2+ and Ag+, which can

Template-controlled mineralization: Determining film granularity and structure by surface functionality patterns

• Nina J. Blumenstein,
• Jonathan Berson,
• Stefan Walheim,
• Petia Atanasova,
• Johannes Baier,
• Joachim Bill and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2015, 6, 1763–1768, doi:10.3762/bjnano.6.180

• sensitivity to topographic features of the SEM. Temperature has a significant influence on the deposition behavior. For higher temperatures, there is bulk precipitation and an inhomogenous film is formed. At lower temperatures, the growth rate is drastically reduced so that film formation is very slow. The

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

• the different methods for iron oxide nanoparticles synthesis, co-precipitation was chosen due to its simplicity, low reaction temperature, short synthesis time, very high yield, and biocompatible product [20]. As previously proposed [19], the molar ratio of Fe+2/Fe+3 = 0.5 and pH 11–12 were applied in

• biocompatible and nontoxic to the cells. Conclusion In summary, this study reports the preparation of two nanocomposites using a three step procedure. The monodisperse, uniform, Fe3O4 nanoparticles were synthesized through a co-precipitation method resulting in a diameter of about 10 nm, followed by surface

• -precipitation. 2.365 g of FeCl3·6H2O and 0.99 g of FeCl2·4H2O were added to 100 mL of distilled and deoxygenated water and stirred about 30 min in the presence of N2. After adding 50 mL of NaOH (2 M) to the mixture, the pH was adjusted to about 12. The color of the mixture turned brown and then black after

Formation of pure Cu nanocrystals upon post-growth annealing of Cu–C material obtained from focused electron beam induced deposition: comparison of different methods

• Aleksandra Szkudlarek,
• Alfredo Rodrigues Vaz,
• Yucheng Zhang,
• Andrzej Rudkowski,
• Czesław Kapusta,
• Rolf Erni,
• Stanislav Moshkalev and
• Ivo Utke

Beilstein J. Nanotechnol. 2015, 6, 1508–1517, doi:10.3762/bjnano.6.156

• microscope. EDX measurements were performed at 5 kV and 2 nA over 30 s with a 300 nm × 300 nm scan area on the squares to account for in homogeneities in the lateral copper nanocrystal precipitation. Standard EDX software was used to calculate the composition from the spectra. High-resolution TEM (HR-TEM

• nanocrystal precipitation on the deposit surface starts at around 150 °C for the Cu(hfac)2 deposits on the pre-patterned SiO2/Si substrate. Further heating to about 200 °C for 30 min did not visibly change the appearance of the Cu nanocrystal precipitation. EDX analysis after conventional heating to 200 °C

• irradiation dose of these regions and hence a slightly less reticulated carbon network which facilitates segregation at many places. For laser-induced heating we found the same phenomenon of surface precipitation of Cu nanocrystals although the annealing time was only one minute. Also the same trend in the