ZnO nanoparticles sensitized by CuInZn_xS_2+x quantum dots as highly efficient solar light driven photocatalysts

• Florian Donat,
• Serge Corbel,
• Halima Alem,
• Steve Pontvianne,
• Lavinia Balan,
• Ghouti Medjahdi and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2017, 8, 1080–1093, doi:10.3762/bjnano.8.110

• and 9). The k values determined were 0.022, 0.024, 0.018 and 0.018 min−1 at pH 3, 5, 7 and 9, respectively. We next conducted photocatalytic experiments in 10 mM solutions of carbonate or phosphate salts that are commonly used to adjust the pH and enhance the dye fixation in textile fabrics (the pH

Recombinant DNA technology and click chemistry: a powerful combination for generating a hybrid elastin-like-statherin hydrogel to control calcium phosphate mineralization

• Mohamed Hamed Misbah,
• Mercedes Santos,
• Luis Quintanilla,
• Christina Günter,
• Matilde Alonso,
• Andreas Taubert and
• José Carlos Rodríguez-Cabello

Beilstein J. Nanotechnol. 2017, 8, 772–783, doi:10.3762/bjnano.8.80

• , D-14476 Potsdam, Germany Institute of Chemistry, University of Potsdam, D-14476 Potsdam, Germany 10.3762/bjnano.8.80 Abstract Understanding the mechanisms responsible for generating different phases and morphologies of calcium phosphate by elastin-like recombinamers is supreme for bioengineering of

• bind to and nucleate calcium phosphate. The benefit of using click chemistry is that the hybrid elastin-like-statherin recombinamers cross-link without losing their fibrillar structure. Mineralization of the resulting hybrid elastin-like-statherin recombinamer hydrogels with calcium phosphate is

• described. Thus, two different hydroxyapatite morphologies (cauliflower- and plate-like) have been formed. Overall, this study shows that crosslinking elastin-like recombinamers leads to interesting matrix materials for the generation of calcium phosphate composites with potential applications as

Selective detection of Mg²⁺ ions via enhanced fluorescence emission using Au–DNA nanocomposites

• Tanushree Basu,
• Khyati Rana,
• Niranjan Das and
• Bonamali Pal

Beilstein J. Nanotechnol. 2017, 8, 762–771, doi:10.3762/bjnano.8.79

• nanoparticles (AuNPs) have attracted a great deal of research interest for various applications in biosensing. AuNPs have strong binding capability to the phosphate and sugar groups in DNA, rendering unique physicochemical properties for detection of metal ions. The formation of Au–DNA nanocomposites is evident

• ]. Also, in DNA, the specific base pairing and the availability of free hydroxyl and phosphate groups have been used to build the structured assembly of particles [4]. DNA-functionalized Au nanoparticles are often applied as nanoscale building blocks in assembly strategies, nanotherapeutics and antisense

• phosphate buffer) was added to the above solution and again incubated at room temperature for 1 h to cleave the disulfide bonds formed by the oligonucleotides upon addition of MPA. DNA functionalized gold nanoparticles were then washed twice by centrifugation (13,000 rpm, 15 min) to remove all unbound

Phospholipid arrays on porous polymer coatings generated by micro-contact spotting

• Sylwia Sekula-Neuner,
• Monica de Freitas,
• Lea-Marie Tröster,
• Tobias Jochum,
• Pavel A. Levkin,
• Michael Hirtz and
• Harald Fuchs

Beilstein J. Nanotechnol. 2017, 8, 715–722, doi:10.3762/bjnano.8.75

• ]. After spotting, the arrays were blocked with 10% bovine serum albumin (BSA) to reduce unspecific binding of the protein to the polymer. Next, samples were washed and incubated for 1 h with 0.5 µg solution of STV-FITC in phosphate buffered saline (PBS). The observed STV-FITC fluorescence is homogenous

Synthesis of graphene–transition metal oxide hybrid nanoparticles and their application in various fields

• Arpita Jana,
• Elke Scheer and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2017, 8, 688–714, doi:10.3762/bjnano.8.74

Silicon microgrooves for contact guidance of human aortic endothelial cells

• Sara Fernández-Castillejo,
• Pilar Formentín,
• Úrsula Catalán,
• Josep Pallarès,
• Lluís F. Marsal and
• Rosa Solà

Beilstein J. Nanotechnol. 2017, 8, 675–681, doi:10.3762/bjnano.8.72

• , Sigma-Aldrich) in a 10 mg/mL solution in phosphate-buffered saline (PBS; pH 7.4) at 4 °C overnight. The substrate was thoroughly washed with PBS and dried with a nitrogen flow. Cell seeding and culture As described before [32][33], HAECs were purchased from Cascade Biologics TM (Portland, USA) and at

Liquid permeation and chemical stability of anodic alumina membranes

• Dmitrii I. Petukhov,
• Dmitrii A. Buldakov,
• Alexey A. Tishkin,
• Alexey V. Lukashin and
• Andrei A. Eliseev

Beilstein J. Nanotechnol. 2017, 8, 561–570, doi:10.3762/bjnano.8.60

• phases having extremely low solubility products. Unfortunately, thermal treatment of anodic alumina films is known to be accompanied by increasing brittleness and possible membrane curling [24][25]. However, none of the pure chemical methods (phosphate or chromate treatment) results in the necessary

Methods for preparing polymer-decorated single exchange-biased magnetic nanoparticles for application in flexible polymer-based films

• Laurence Ourry,
• Delphine Toulemon,
• Souad Ammar and
• Fayna Mammeri

Beilstein J. Nanotechnol. 2017, 8, 408–417, doi:10.3762/bjnano.8.43

• of the resulting hybrid, namely polymer chains and inorganic NPs (e.g., covalent, ionic, van der Waals). Several halogenated coupling agents can be used to covalently graft an organic group onto the surface of oxide NPs, e.g., organosilanes [21][22][23], carboxylate [24][25] or phosphonate/phosphate

• the catalyst. The length of the carbon backbone of the initiator (between phosphate and α-bromo-ester functions) is very important to the ATRP polymerization rate when initiators are directly anchored to the particle surface. Sunday et al. [36] reported that long alkyl chains (16 carbon atoms) or

Biological and biomimetic materials and surfaces

• Stanislav Gorb and
• Thomas Speck

Beilstein J. Nanotechnol. 2017, 8, 403–407, doi:10.3762/bjnano.8.42

• articles of this Thematic Series, Egorov et al. proposed a relatively simple protocol for 3D printing of complex-shaped biocompatible structures based on sodium alginate and calcium phosphate for bone tissue engineering [24]. The analysis of 3D printed structures shows that they possess large

Uptake of the proteins HTRA1 and HTRA2 by cells mediated by calcium phosphate nanoparticles

• Olga Rotan,
• Katharina N. Severin,
• Simon Pöpsel,
• Alexander Peetsch,
• Melisa Merdanovic,
• Michael Ehrmann and
• Matthias Epple

Beilstein J. Nanotechnol. 2017, 8, 381–393, doi:10.3762/bjnano.8.40

• membrane, which is a problem if an intracellular mode of action is desired, for example, with a nuclear receptor. Calcium phosphate nanoparticles can serve as carriers for small and large biomolecules as well as for synthetic compounds. The nanoparticles were prepared and colloidally stabilized with either

• flow cytometry. All proteins were readily transported into the cells by cationic calcium phosphate nanoparticles. Notably, only HTRA1 was able to penetrate the cell membrane of MG-63 cells in dissolved form. However, the application of endocytosis inhibitors revealed that the uptake pathway was

• different for dissolved HTRA1 and HTRA1-loaded nanoparticles. Keywords: calcium phosphate; endocytosis; nanoparticles; proteins; Introduction Many receptors for drugs or proteins are located inside cells [1][2]. However, because many biomolecules are not able to penetrate the cell membrane on their own, a

Comparison of four methods for the biofunctionalization of gold nanorods by the introduction of sulfhydryl groups to antibodies

• Xuefeng Wang,
• Zhong Mei,
• Yanyan Wang and
• Liang Tang

Beilstein J. Nanotechnol. 2017, 8, 372–380, doi:10.3762/bjnano.8.39

• previously described [19]. Briefly, 0.1 mL of anti-IgG was reconstituted in Buph PBS (0.1 M sodium phosphate, 0.15 M NaCl, pH 7.2) containing 10 mM EDTA. Then, 5 μL DTT (1 M) dissolved in Buph PBS/10 mM EDTA were added to the IgG solution. The samples were mixed and reacted on a rotator at room temperature

Nanoscale isoindigo-carriers: self-assembly and tunable properties

• Tatiana N. Pashirova,
• Andrei V. Bogdanov,
• Lenar I. Musin,
• Julia K. Voronina,
• Irek R. Nizameev,
• Marsil K. Kadirov,
• Vladimir F. Mironov,
• Lucia Ya. Zakharova,
• Shamil K. Latypov and
• Oleg G. Sinyashin

Beilstein J. Nanotechnol. 2017, 8, 313–324, doi:10.3762/bjnano.8.34

• stability of these fabricated SIPs was evaluated under in vitro conditions. After 3 h dialysis in phosphate buffer (pH 7.4) at 37 °C the size of 2d SIPs was shown to increase, with the polydispersity index reaching values greater than 0.4 (Figure S2, Supporting Information File 1). Homologues 2b and 2e form

• 2h aggregates increased when using phosphate buffer instead of water during preparation of the colloidal aggregates (Figure S7, Supporting Information File 1). To predict the morphology of aggregates, the packing parameter P [65] was calculated for all compounds by using Equation 1: The dimensionless

• solution (0.5 mL) was added in 1 min to deionized water (25 mL) or phosphate buffer (25 mL) at 60 °C and stirred at 750 rpm. Nanoparticles were formed spontaneously. Solvent (THF) and part of water were removed under reduced pressure and the total volume was adjusted to 25 mL with deionized water. Methods

Comparison of four functionalization methods of gold nanoparticles for enhancing the enzyme-linked immunosorbent assay (ELISA)

• Paula Ciaurriz,
• Fátima Fernández,
• Edurne Tellechea,
• Jose F. Moran and
• Aaron C. Asensio

Beilstein J. Nanotechnol. 2017, 8, 244–253, doi:10.3762/bjnano.8.27

• (Ab) and HRP were oxidized with periodate and incubated with the linker hydrazine dithiol. Briefly, 100 μL of Ab 1 mg/mL was incubated with 30 μL of 100 mM phosphate pH 7.4 and 10 μL of periodate 100 mM protected from light for 30 min. In the case of peroxidase, 200 μL of HRP 3 mg/mL were incubated

• buffer exchanged against phosphate buffer 10 mM pH 7.4 using a Hi-Trap desalting column using an Äkta Prime apparatus (GE-Healthcare, Upsala, Sweden). The Ab-linker and HRP-linker concentrations were measured by absorption at 280 nm and 403 nm, respectively, as well as by Bradford assay (data not shown

• re-suspended in 1 mL phosphate buffer 10 mM pH 7.4 containing 0.5% BSA and 0.01% Tween 20. This step was repeated twice but after the last wash, the complex was re-suspended in 400 µL. The complex concentration was measured by absorption at 520 nm and kept at 4 °C until use. In case of the

Surface-enhanced Raman scattering of self-assembled thiol monolayers and supported lipid membranes on thin anodic porous alumina

• Marco Salerno,
• Amirreza Shayganpour,
• Barbara Salis and
• Silvia Dante

Beilstein J. Nanotechnol. 2017, 8, 74–81, doi:10.3762/bjnano.8.8

• living cells, we decided to test the tAPA–Au SERS-active substrates on SLBs in phosphate-buffered saline (PBS) buffer solution, which provide an excellent model system to mimic the native cellular membranes [22]. In the present work, the fabrication and modification of tAPA aiming at its exploitation as

Streptavidin-coated gold nanoparticles: critical role of oligonucleotides on stability and fractal aggregation

• Roberta D'Agata,
• Pasquale Palladino and
• Giuseppe Spoto

Beilstein J. Nanotechnol. 2017, 8, 1–11, doi:10.3762/bjnano.8.1

• genomic DNA [13], were purchased from Thermo Fisher Scientific, Inc. Streptavidin from Streptomyces avidinii, provided in lyophilized form in 10 mM PBS, pH 7.4, was purchased from Invitrogen (Italy). Mixed cellulose ester membrane filters were purchased from Whatman (UK). Phosphate buffered saline (PBS

• ) solutions at pH 7.4 (137 mM NaCl, 2.7 mM KCl, phosphate buffered 10 mM) were obtained from Amresco (Italy). Ultra-pure water (Milli-Q Element, Millipore) was used for all the experiments. Synthesis of AuNPs Glassware was cleaned with freshly prepared “piranha” solution; i.e., a mixture of 1:3 ratio of

• assured the nanoparticles stability for several months. The resulting colloidal solution was characterized by λmax = 520 nm. AuNPs functionalization Adsorption of SA on AuNPs was achieved by adding 10 µL of SA solution (1 mg mL−1 in 10 mM sodium phosphate buffer pH 7.4, the final concentration of SA in

A novel electrochemical nanobiosensor for the ultrasensitive and specific detection of femtomolar-level gastric cancer biomarker miRNA-106a

• Maryam Daneshpour,
• Kobra Omidfar and
• Hossein Ghanbarian

Beilstein J. Nanotechnol. 2016, 7, 2023–2036, doi:10.3762/bjnano.7.193

• . Afterward, the particles were exposed to 20 µg of streptavidin and the volume was adjusted to 500 µL with phosphate buffer saline (PBS) (0.01%, pH 7.4). The resulting suspension was incubated under shaking condition at room temperature for 1 h. The particles were washed and magnetically separated. In order

Effect of Anderson localization on light emission from gold nanoparticle aggregates

• Mohamed H. Abdellatif,
• Marco Salerno,
• Gaser N. Abdelrasoul,
• Ioannis Liakos,
• Alice Scarpellini,
• Sergio Marras and
• Alberto Diaspro

Beilstein J. Nanotechnol. 2016, 7, 2013–2022, doi:10.3762/bjnano.7.192

• phosphate, potassium titanyl phosphate or lithium niobate. This effect can be ascribed to the fractal-like shape or statistical self-similarity of the AuNP arrangement [14]. The concept of fractal-like design in optics was introduced for the first time by Stockman [14]. In a chain of particles, the self

Layered composites of PEDOT/PSS/nanoparticles and PEDOT/PSS/phthalocyanines as electron mediators for sensors and biosensors

• Celia García-Hernández,
• Cristina García-Cabezón,
• Fernando Martín-Pedrosa,
• José Antonio De Saja and
• María Luz Rodríguez-Méndez

Beilstein J. Nanotechnol. 2016, 7, 1948–1959, doi:10.3762/bjnano.7.186

• /PSS/EM electrodes were analyzed using cyclic voltammetry. Voltammograms of PEDOT/PSS, PEDOT/PSS/AuNPs, PEDOT/PSS/CuPc and PEDOT/PSS/LuPc2 electrodes immersed in catechol and hydroquinone 1.5 × 10−4 mol·L−1 with 0.01 mol·L−1 phosphate buffer as the supporting electrolyte are shown in Figure 2. The

• Trametes versicolor, activity ≥10 U·mg−1). 5 mg·L−1 solutions of tyrosinase and laccase were prepared in buffered phosphate 0.01 mol·L−1 (pH 7.0). Preparation of the electrochemical sensors and biosensors Sensors were prepared using a spin coater, model 1H-D7 (Micasa Co., Tokyo, Japan). ITO glass

• at 2000 rpm for 120 s (slope of 120 s), followed by annealing at 150 °C for 15 min. PEDOT/PSS/EM enzymatic biosensors were prepared by depositing laccase or tyrosinase onto the PEDOT/PSS/EM sensors. For this purpose, 50 μL of 0.01 mol·L−1 phosphate buffer (pH 7.0) containing 5 mg·mL−1 of enzyme were

Facile fabrication of luminescent organic dots by thermolysis of citric acid in urea melt, and their use for cell staining and polyelectrolyte microcapsule labelling

• Nadezhda M. Zholobak,
• Anton L. Popov,
• Alexander B. Shcherbakov,
• Nelly R. Popova,
• Mykhailo M. Guzyk,
• Valeriy P. Antonovich,
• Alla V. Yegorova,
• Yuliya V. Scrypynets,
• Inna I. Leonenko,
• Alexander Ye. Baranchikov and
• Vladimir K. Ivanov

Beilstein J. Nanotechnol. 2016, 7, 1905–1917, doi:10.3762/bjnano.7.182

• -delivery vehicles in living beings [31][32]. Earlier, such microcapsules had been decorated using other luminescent labels, including organic dyes [33], rare-earth phosphate nanocrystals [34] and visible [35][36] or near-infrared emitting chalcogenide Q-dots [36]. Results and Discussion O-dot formation and

• was determined, according to the protocol of the manufacturer. Cellular staining We used two methods for visualizing cells by synthesized O-dots: without fixing, and with fixing, using a mixture containing 2.5% glutaraldehyde (Sigma) and 4% paraformaldehyde (Sigma) in phosphate-buffered saline (pH 7.2

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

• calcium phosphate (CP) for bone tissue engineering. The fabrication of 3D composite structures was performed through the synthesis of inorganic particles within a biopolymer macromolecular network during 3D printing process. The formation of a new CP phase was studied through X-ray diffraction, Fourier

• diameter ≈800 μm) and were found to possess compressive strengths from 0.45 to 1.0 MPa. This new approach can be effectively applied for fabrication of biocompatible scaffolds for bone tissue engineering constructions. Keywords: 3D printing; bone graft; calcium phosphate; composite materials; sodium

• pores sizes and good interconnectivity, which are of great importance for the design of 3D bone substitutes for biomedical applications. The CP phase was formed upon mixing of the polymer slurry containing ammonium hydrogen phosphate with a calcium chloride aqueous solution during the printing process

Surface-enhanced infrared absorption studies towards a new optical biosensor

• Lothar Leidner,
• Julia Stäb,
• Jennifer T. Adam and
• Günter Gauglitz

Beilstein J. Nanotechnol. 2016, 7, 1736–1742, doi:10.3762/bjnano.7.166

• added by aggregation of nanoparticles. Addition of concentrated phosphate buffered saline (PBS, 10× concentrate) to the water–nanoparticles system causes the aggregation due to the salt effect of PBS. Figure 1 shows the results obtained with the Teflon AF2400 sensor (GaAs etalon, 6 mm thickness, coated

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

• ; Introduction Hydroxyapatite (HAp) is a naturally occurring mineral (a form of calcium apatite), which is also an inorganic component of bones, with approximately 8 wt % water, 22 wt % protein and 70 wt % mineral. HAp is a form of calcium phosphate with the chemical formula Ca10(PO4)6(OH)2 and a hexagonal

• quantity of the crystalline phase in comparison with the content of the amorphous phase present in a material. HAp crystallization occurs in accordance with the Ostwald’s rule, so it usually forms from recrystallization of such precursor phases as octacalcium phosphate (OCP), dicalcium phosphate dihydrate

• (DCPD) and amorphous calcium phosphate (ACP) [55]. HAp crystallization during the synthesis ensues in accordance with the mechanism of crystallization from a solution. During the growth process, particles may grow on the surface of sediment or precipitate in all directions. Their growth may be expected

On the pathway of cellular uptake: new insight into the interaction between the cell membrane and very small nanoparticles

• Claudia Messerschmidt,
• Daniel Hofmann,
• Anja Kroeger,
• Katharina Landfester,
• Volker Mailänder and
• Ingo Lieberwirth

Beilstein J. Nanotechnol. 2016, 7, 1296–1311, doi:10.3762/bjnano.7.121

• increasing the permeability of the plasma membrane. The accumulation of calcium taking the form of insoluble hydroxyapatite (Ca phosphate) inside mitochondria during a necrotic process is a well-known and documented phenomenon during this process [37][38]. A lot of data concerning cytotoxicity of

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

• the dispersion stability of PM-b-PEG/SPIO@oMWCNT#Liu in phosphate-buffered saline (PSB) and in water, thus proving that the presence of the amphiphilic polymer PMETAC-b-PEGMA prevents sedimentation [33]. CoFe2O4/oMWCNT#Wu formed a stable aqueous dispersion for 2 weeks [39]. Maciejewska reported the

Improved biocompatibility and efficient labeling of neural stem cells with poly(L-lysine)-coated maghemite nanoparticles

• Igor M. Pongrac,
• Marina Dobrivojević,
• Lada Brkić Ahmed,
• Michal Babič,
• Miroslav Šlouf,
• Daniel Horák and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 926–936, doi:10.3762/bjnano.7.84

• ) cells. Prussian blue staining After labeling, nanoparticles were removed, cells were washed three times with phosphate buffered saline (PBS), fixed with 4% paraformaldehyde (Sigma-Aldrich) for 20 min, and stained with a 1:1 mixture of 10% K4Fe(CN)6 (Sigma-Aldrich) and 20% HCl for 20 min. Cells were

• reagent, washed once with DMEM/F-12 medium, separated by centrifugation and fixed overnight with 2% glutaraldehyde in 0.1 M phosphate buffer, post-fixed in 1% osmium tetroxide, and contrasted in 2% uranyl acetate in water. The samples were dehydrated in acetone and embedded in resin Durcupan (Sigma