Patterning of supported gold monolayers via chemical lift-off lithography

• Liane S. Slaughter,
• Kevin M. Cheung,
• Sami Kaappa,
• Huan H. Cao,
• Qing Yang,
• Thomas D. Young,
• Andrew C. Serino,
• Sami Malola,
• Jana M. Olson,
• Stephan Link,
• Hannu Häkkinen,
• Anne M. Andrews and
• Paul S. Weiss

Beilstein J. Nanotechnol. 2017, 8, 2648–2661, doi:10.3762/bjnano.8.265

• supported Au–thiolate layers. The patterning of these layers laterally encodes their functionality, as demonstrated by a fluorescence-based approach that relies on dye-labeled complementary DNA hybridization. Supported thin Au films can be patterned via features on PDMS stamps (controlled contact), using

• regions containing Au–alkanethiolates appeared bright in fluorescence microscopy images (Figure 2). Using this straightforward functionalization and visualization method, we investigated patterns of lifted-off Au monolayers on PDMS as substrates for DNA recognition. Upon hybridization of dye-labeled

• complementary strands, fluorescent patterns were readily observed (Figure 2A,C,D). No measurable fluorescence was detected when DNA-functionalized substrates were exposed to dye-labeled non-complementary DNA (Figure 2B). Thus, the fluorescence patterns observed in Figure 2 derive from specific hybridization

Dynamic behavior of a nematic liquid crystal mixed with CoFe₂O₄ ferromagnetic nanoparticles in a magnetic field

• Emil Petrescu,
• Cristina Cirtoaje and
• Cristina Stan

Beilstein J. Nanotechnol. 2017, 8, 2467–2473, doi:10.3762/bjnano.8.246

• and f is the volume fraction of the magnetic particles. Considering the dynamic evolution of a liquid crystal system as presented in [34], we can evaluate the temporal evolution of the distortion angle using the model similar to the one used in [30]. In this model, the term used for an azo-dye

Involvement of two uptake mechanisms of gold and iron oxide nanoparticles in a co-exposure scenario using mouse macrophages

• Dimitri Vanhecke,
• Dagmar A. Kuhn,
• Dorleta Jimenez de Aberasturi,
• Sandor Balog,
• Ana Milosevic,
• Dominic Urban,
• Diana Peckys,
• Niels de Jonge,
• Wolfgang J. Parak,
• Alke Petri-Fink and
• Barbara Rothen-Rutishauser

Beilstein J. Nanotechnol. 2017, 8, 2396–2409, doi:10.3762/bjnano.8.239

• to remove any leftover dye. The samples were immediately examined after the labelling. Laser scanning microscopy and data restoration Image acquisition was performed with an inverted Zeiss LSM 710 Meta apparatus (Axio Observer.Z1, Zeiss, Switzerland) equipped with 405 nm diode, and 488, 561 and 633

Photobleaching of YOYO-1 in super-resolution single DNA fluorescence imaging

• Joseph R. Pyle and
• Jixin Chen

Beilstein J. Nanotechnol. 2017, 8, 2296–2306, doi:10.3762/bjnano.8.229

• ) has great potential to visualize fine DNA structures with nanometer resolution. In a typical PAINT video acquisition, dye molecules (YOYO-1) in solution sparsely bind to the target surfaces (DNA) whose locations can be mathematically determined by fitting their fluorescent point spread function. Many

• ], DNA protein studies [6][7], and optical mapping [8][9][10]. YOYO-1 is a common dye chosen for these studies due to its favorable optical properties. YOYO-1 has a high extinction coefficient of 105 M−1 cm−1 [11] and strongly binds to DNA (binding constant 108–109 M−1) [12] with little sequence

• , photoswitching, or a combination thereof [34][37][38]. Dye photobleaching is one of the most utilized methods in PAINT fluorescently turn-off the dye molecules and is commonly used in most all types of fluorescent imaging [17][19][20][39][40]. Thus, carefully tuning the photobleaching rate is an important step

Fabrication of gold-coated PDMS surfaces with arrayed triangular micro/nanopyramids for use as SERS substrates

• Jingran Zhang,
• Yongda Yan,
• Peng Miao and
• Jianxiong Cai

Beilstein J. Nanotechnol. 2017, 8, 2271–2282, doi:10.3762/bjnano.8.227

• rhodamine 6G (R6G) were detected as test analytes [17]. The micro/nanostructures of a blue butterfly wing were used as a template, and a SERS substrate was produced and utilized to detect rhodamine dye for the elimination of organic pollutants [19]. Additionally, pyramidal array structures on conventional

• nm thick gold film with a dye concentration of 10−6 M. The characteristic Raman peaks of R6G molecules were successfully identified at 612, 771, 1183, 1311, 1362, 1504 and 1603 cm−1, as shown in Figure 6a. Owing to the different microstructures formed by the feeds in the X and Y directions, it can be

• concentration of the dye molecule in the SERS and normal Raman measurements, in this case using a 0.25 mol R6G solution on a SiO2 wafer. The SERS enhancement factor for the various micro/nanostructures is between 7.5 × 105 and 6 × 106 for the structured PDMS substrate formed by the method described in the

Evaluating the toxicity of TiO₂-based nanoparticles to Chinese hamster ovary cells and Escherichia coli: a complementary experimental and computational approach

• Alicja Mikolajczyk,
• Natalia Sizochenko,
• Ewa Mulkiewicz,
• Anna Malankowska,
• Michal Nischk,
• Przemyslaw Jurczak,
• Seishiro Hirano,
• Grzegorz Nowaczyk,
• Adriana Zaleska-Medynska,
• Jerzy Leszczynski,
• Agnieszka Gajewicz and
• Tomasz Puzyn

Beilstein J. Nanotechnol. 2017, 8, 2171–2180, doi:10.3762/bjnano.8.216

• alters the rate of chemical reactions, when exposed to light (photocatalyst) [1]. TiO2-based NPs have already found wide applications as efficient photocatalysts for sterilization, sanitation, air and water purification systems, hydrogen production by water splitting, and dye-sensitized solar cells [1

• ), platinum (Pt), or palladium (Pd) [13][14], (e) the use of dye-modified TiO2 [15][16], or (f) coupling TiO2 with other semiconductors [17][18]. In the current work, we will focus on surface modification methods. Metal-ion doped TiO2 (so-called second generation nanomaterials) may cause adverse effects not

Synthesis and characterization of noble metal–titania core–shell nanostructures with tunable shell thickness

• Bartosz Bartosewicz,
• Marta Michalska-Domańska,
• Malwina Liszewska,
• Dariusz Zasada and
• Bartłomiej J. Jankiewicz

Beilstein J. Nanotechnol. 2017, 8, 2083–2093, doi:10.3762/bjnano.8.208

• interesting materials for application in dye-sensitized solar cells (DSSCs) and photocatalysis. In fact, it has been shown that plasmonic nanostructures can enhance the efficiency of DSSCs by four possible mechanisms [66]. The far-field coupling of scattered light and the near-field coupling of

Fabrication of carbon nanospheres by the pyrolysis of polyacrylonitrile–poly(methyl methacrylate) core–shell composite nanoparticles

• Dafu Wei,
• Youwei Zhang and
• Jinping Fu

Beilstein J. Nanotechnol. 2017, 8, 1897–1908, doi:10.3762/bjnano.8.190

• timely discharge of the gases from the PAN-based nanoparticles. The formation of large pores, i.e., mesopores may be attributed to the residual gases which remain inside the nanoparticles. The carbonized sample CP6 was further applied as an adsorbent for removal of methylene blue (MB) (a common dye used

Carbon nano-onions as fluorescent on/off modulated nanoprobes for diagnostics

• Stefania Lettieri,
• Marta d’Amora,
• Adalberto Camisasca,
• Alberto Diaspro and
• Silvia Giordani

Beilstein J. Nanotechnol. 2017, 8, 1878–1888, doi:10.3762/bjnano.8.188

• boron dipyrromethene (BODIPY) dye with on/off modulated fluorescence emission activated by an acidic environment. The switching properties are linked to the photoinduced electron transfer (PET) characteristics of the dimethylamino functionalities attached to the BODIPY core. The on/off emission of the

• biocompatibility [20]. We have previously shown that the pH-dependent switching ability of a dye is preserved when attached to CNOs [21] and on single-wall carbon nanotubes, [22] both in solution and in vitro. Thus, CNOs are suitable nanomaterials for biosensing applications. We exploited the photoinduced electron

• transfer (PET) and internal charge transfer (ICT) donor characteristics of the dimethylamino functionalities attached to a π-extended distyryl-substituted boron dipyrromethene (BODIPY) dye [23][24] to obtain a pH-sensitive nano-probe. Hence, CNOs grafted with BODIPY 3 molecules (fluo-CNOs) led to the

Collembola cuticles and the three-phase line tension

• Håkon Gundersen,
• Hans Petter Leinaas and
• Christian Thaulow

Beilstein J. Nanotechnol. 2017, 8, 1714–1722, doi:10.3762/bjnano.8.172

• experiment with a fluorescent dye revealed the extent of wetting on exposed surface structures. Using simple wetting models to describe the composite wetting of the cuticular surface structures results in underestimating the contact angles of water. Including the three-phase line tension allows for a

• values of λ. Changing the inherent contact angle shifts both the minimum value of and the critical range of λ. We propose that the composite wetting state assumed by the Cassie–Baxter model, as well as the derivative Zheng model, can be demonstrated by a novel wetting experiment with a dye. Nickerl et

• al demonstrated a lipid layer (epicuticular wax) covering all parts of the Collembola cuticle, using time-of-flight secondary ion mass spectrometry [30]. A lipophilic dye, such as Nile Red, will bind to any part of such a layer it came into contact with, thus staining the part of a surface wetted by

Three-in-one approach towards efficient organic dye-sensitized solar cells: aggregation suppression, panchromatic absorption and resonance energy transfer

• Jayita Patwari,
• Samim Sardar,
• Bo Liu,
• Peter Lemmens and
• Samir Kumar Pal

Beilstein J. Nanotechnol. 2017, 8, 1705–1713, doi:10.3762/bjnano.8.171

• , Mendelssohnstraße 3, 38106 Braunschweig, Germany Laboratory for Emerging Nanometrology, TU Braunschweig, Braunschweig, Germany 10.3762/bjnano.8.171 Abstract In the present study, protoporphyrin IX (PPIX) and squarine (SQ2) have been used in a co-sensitized dye-sensitized solar cell (DSSC) to apply their high

• absorption coefficients in the visible and NIR region of the solar spectrum and to probe the possibility of Förster resonance energy transfer (FRET) between the two dyes. FRET from the donor PPIX to acceptor SQ2 was observed from detailed investigation of the excited-state photophysics of the dye mixture

• , using time-resolved fluorescence decay measurements. The electron transfer time scales from the dyes to TiO2 have also been characterized for each dye. The current–voltage (I–V) characteristics and the wavelength-dependent photocurrent measurements of the co-sensitized DSSCs reveal that FRET between the

Uptake and intracellular accumulation of diamond nanoparticles – a metabolic and cytotoxic study

• Antonín Brož,
• Lucie Bačáková,
• Pavla Štenclová,
• Alexander Kromka and
• Štěpán Potocký

Beilstein J. Nanotechnol. 2017, 8, 1649–1657, doi:10.3762/bjnano.8.165

• samples were then washed with phosphate buffered saline and were fixed with 4% paraformaldehyde for 10 min. The nuclei of the fixed cells were then stained using Hoechst 33258 dye for cell counting. Micrographs of the stained nuclei were acquired using an IX71 microscope (Olympus, Japan) with a 10× lens

Development of an advanced diagnostic concept for intestinal inflammation: molecular visualisation of nitric oxide in macrophages by functional poly(lactic-co-glycolic acid) microspheres

• Kathleen Lange,
• Christian Lautenschläger,
• Maria Wallert,
• Stefan Lorkowski,
• Andreas Stallmach and
• Alexander Schiller

Beilstein J. Nanotechnol. 2017, 8, 1637–1641, doi:10.3762/bjnano.8.163

• ) (PLGA). PLGA microspheres loaded with NO550 dye were prepared through a modified solvent-evaporation method. Microparticles were characterized by a mean hydrodynamic diameter of 3000 nm, zeta potential of −26.000 ± 0.351 mV and a PDI of 0.828 ± 0.298. Under abiotic conditions, NO release was triggered

• visualise these cells in NO-mediated intestinal inflammation in vivo by fluorescent particle-based diagnostics in a second step. Here, we used a NO-sensitive dye, namely NO550, as a model molecule to proof the concept of a particle-based diagnostic as part of an advanced diagnostic concept for detecting

• -stimulated cells as determined by the Griess reaction (Figure 4). Conclusion We demonstrated the possibility of molecular imaging of NO at different concentrations and under different conditions using NO550-loaded PLGA microspheres in living macrophages. NO550 is converted by NO into an azo dye, which emits

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

Luminescent supramolecular hydrogels from a tripeptide and nitrogen-doped carbon nanodots

• Maria C. Cringoli,
• Slavko Kralj,
• Marina Kurbasic,
• Massimo Urban and
• Silvia Marchesan

Beilstein J. Nanotechnol. 2017, 8, 1553–1562, doi:10.3762/bjnano.8.157

• the sustained release of the poorly soluble antibiotic ciprofloxacin [26]. Fluorescent hydrogels were formed from co-assembly with a dye into nanostructures of different morphology, depending on whether the dye was added initially to the peptide in the alkaline buffer solution, or later to the second

• NCND effects on the peptide supramolecular structure. Thioflavin T is a dye that binds to hydrophobic grooves formed by at least four consecutive beta-strands, leading to fluorescence that is used to assess the peptide amyloid character [35]. Fluorescence arises from the limited rotation of a single

• bond between two aromatic rings composing the dye, namely the benzothiazole and the dimethylanilino units [36]. Although its fluorescence can also be increased by an increase of solvent viscosity [36], in aqueous environments, it is effectively and universally used as an amyloid marker thanks to its

Calcium fluoride based multifunctional nanoparticles for multimodal imaging

• Marion Straßer,
• Joachim H. X. Schrauth,
• Sofia Dembski,
• Daniel Haddad,
• Bernd Ahrens,
• Stefan Schweizer,
• Bastian Christ,
• Alevtina Cubukova,
• Marco Metzger,
• Heike Walles,
• Peter M. Jakob and
• Gerhard Sextl

Beilstein J. Nanotechnol. 2017, 8, 1484–1493, doi:10.3762/bjnano.8.148

• the ions in the calcium fluoride lattice (proof of principle). For a later clinical usage certainly we have to exchange terbium for a NIR dye or something similar because of the high sensitivity of living tissues towards UV light. In Figure 3 the emission spectrum of CaF2:(Tb3+,Gd3+) NPs at an

Low uptake of silica nanoparticles in Caco-2 intestinal epithelial barriers

• Dong Ye,
• Mattia Bramini,
• Delyan R. Hristov,
• Sha Wan,
• Anna Salvati,
• Christoffer Åberg and
• Kenneth A. Dawson

Beilstein J. Nanotechnol. 2017, 8, 1396–1406, doi:10.3762/bjnano.8.141

• Discussion Particle physicochemical characterisation Green fluorescent silica nanoparticles (SiO2-NPs) of 50 and 150 nm diameter were synthesized according to previous literature [42]. In order to remove eventual free fluorescent dye releasing from the labelled nanoparticles [3][43][44], the nanoparticle

• stocks were cleaned (by pelleting and resuspending in fresh buffer) prior to experiments with cells. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that for both nanoparticles, no labile dye was present in the nanoparticle dispersions (Supporting Information File 1

• , Figure S1). Based upon previous experience, we limited exposure times to 6 hours in order to reduce the risk of released free dye and fragmentation of the nanoparticles, stemming from partial solubility in cell culture medium, which could confuse uptake and transport studies [42]. Nanoparticle size and

Carbon nanomaterials sensitize prostate cancer cells to docetaxel and mitomycin C via induction of apoptosis and inhibition of proliferation

• Kati Erdmann,
• Jessica Ringel,
• Silke Hampel,
• Manfred P. Wirth and
• Susanne Fuessel

Beilstein J. Nanotechnol. 2017, 8, 1307–1317, doi:10.3762/bjnano.8.132

• interference between the water-soluble formazan dye and CNTs has been detected [32]. As reported previously, both CNFs and CNTs impaired cellular viability only marginally in addition to low to moderate effects on cellular proliferation and clonogenic survival [28]. Compared to untreated control cells, both

• Cellular viability was quantified in quintuplicate in 96-well culture plates using the cell proliferation reagent WST-1 (Roche, Mannheim, Germany), for which no interaction between the water-soluble formazan dye and CNTs has been observed [32]. WST-1 reagent was added to the cells 72 h after end of

Fabrication of hierarchically porous TiO₂ nanofibers by microemulsion electrospinning and their application as anode material for lithium-ion batteries

• Jin Zhang,
• Yibing Cai,
• Xuebin Hou,
• Xiaofei Song,
• Pengfei Lv,
• Huimin Zhou and
• Qufu Wei

Beilstein J. Nanotechnol. 2017, 8, 1297–1306, doi:10.3762/bjnano.8.131

• et al. reported the fabrication of hierarchical TiO2 nanorods via ME-ES and the application as photoanode material for dye-sensitized solar cells [25]. According to Shi et al., highly porous SnO2/TiO2 composite nanofibers were prepared successfully by ME-ES and subsequent calcination [28]. There are

Bright fluorescent silica-nanoparticle probes for high-resolution STED and confocal microscopy

• Isabella Tavernaro,
• Christian Cavelius,
• Henrike Peuschel and
• Annette Kraegeloh

Beilstein J. Nanotechnol. 2017, 8, 1283–1296, doi:10.3762/bjnano.8.130

• , fluorescent nanomaterials have gained high relevance in biological applications as probes for various fluorescence-based spectroscopy and imaging techniques. Among these materials, dye-doped silica nanoparticles have demonstrated a high potential to overcome the limitations presented by conventional organic

• agglomeration and stability) and the fluorescence properties of the obtained particles were compared to particles from commonly known synthesis methods. As a result, the spectroscopic characteristics of the presented monodisperse dye-doped silica nanoparticles were similar to those of the free uncoupled dyes

• depletion (STED) microscopy. Our approach allows for a step-by-step formation of dye-doped silica nanoparticles in the form of dye-incorporated spheres, which can be used as versatile fluorescent probes in confocal and STED imaging. Keywords: bioimaging; confocal microscopy; multistep synthesis approach

Evaluation of quantum dot conjugated antibodies for immunofluorescent labelling of cellular targets

• Jennifer E. Francis,
• David Mason and
• Raphaël Lévy

Beilstein J. Nanotechnol. 2017, 8, 1238–1249, doi:10.3762/bjnano.8.125

• -Ab) was tested against several primary IgG antibodies. The antigens were labelled simultaneously with a fluorescent dye coupled to a secondary antibody (Dye-Ab) and the Qdot-Ab. Although, the Dye-Ab labelled all of the intended target proteins, the Qdot-Ab was found bound to only some of the protein

• characteristics, the overall hydrodynamic radius of a Qdot (15–20 nm) is much larger than that of a fluorescent dye molecule [12][13][14]. As a result, one large Qdot may host many antibodies, whereas many fluorescent dye molecules can be coupled to a single antibody [9][15]. Furthermore, the overall size of

• emission maxima of 625 nm (excitation and emission spectra available in Figure S1 in Supporting Information File 1), in fixed cells (Figure 1). Different protein targets were labelled simultaneously with both a secondary antibody conjugated to a fluorescent dye (Dye-Ab) and a Qdot 625 conjugated secondary

Nano-engineered skin mesenchymal stem cells: potential vehicles for tumour-targeted quantum-dot delivery

• Liga Saulite,
• Dominyka Dapkute,
• Karlis Pleiko,
• Ineta Popena,
• Simona Steponkiene,
• Ricardas Rotomskis and
• Una Riekstina

Beilstein J. Nanotechnol. 2017, 8, 1218–1230, doi:10.3762/bjnano.8.123

• 100%. After incubation, 10 µL of CCK-8 reagent was added to each well and incubated for 2 h at 37 °C in 5% CO2 at 90% humidity. The change in the medium colour corresponds to the amount of dye produced in the sample and is directly proportional to the number of viable cells. The optical density was

Enhanced catalytic activity without the use of an external light source using microwave-synthesized CuO nanopetals

• Govinda Lakhotiya,
• Sonal Bajaj,
• Arpan Kumar Nayak,
• Debabrata Pradhan,
• Pradip Tekade and
• Abhimanyu Rana

Beilstein J. Nanotechnol. 2017, 8, 1167–1173, doi:10.3762/bjnano.8.118

• also under dark conditions for the degradation of the hazardous dye methylene blue. The CuO nanopetals showed significant catalytic activity for the fast degradation of methylene blue and rhodamine B (RhB) under dark conditions, without the application of an external light source. This increased

• of these dyes. This is attributed to the role of H2O2 and the large specific surface area of the nanopetals. The amount of the catalyst (CuO nanopetals) and the hazardous H2O2 is minimized, and the reproducibility of the degradation of the dye with the same catalyst has been tested. The catalytic

• the degradation through the formation of radicals [6][25]. The wide band gap, high surface area of CuO nanopetals was expected to be suitable for the photocatalytic activity for the degradation of the common cationic dye methylene blue (MB), and hence initially, a study has been carried out in which

Hierarchically structured nanoporous carbon tubes for high pressure carbon dioxide adsorption

• Julia Patzsch,
• Deepu J. Babu and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2017, 8, 1135–1144, doi:10.3762/bjnano.8.115

• sensors [30][31][32] or photoelectrodes for dye-sensitive solar cells [33]. This technique has also be extended for the synthesis of one-dimensional metal oxide nanomaterials [34][35][36][37]. Herein, we introduce a process which allows highly porous carbon tubes as well as nanocrystalline silicon carbide

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

• nanoparticles exhibit a high photocatalytic activity under simulated solar light irradiation for the degradation of Orange II dye (>95% degradation after 180 min of irradiation at an intensity of 5 mW/cm2). The heterojunction built between the ZnO nanoparticle and ZCIS QDs not only extends the light adsorption

• generating UV-A and UV-B radiation. In this paper, we report first the successful preparation of a ZnO/ZCIS heterostructured photocatalyst using commercial ZnO nanoparticles and only 2.5 wt % of ZCIS QDs. The high photocatalytic activity of this material for the degradation of Orange II dye under simulated

• both under solar and visible light illumination (light intensity = 5 mW/cm2) of all the ZnO/ZCIS composites prepared, we selected Orange II dye as a model contaminant because this dye is not a photosensitizer (in contrast to Methylene Blue or Rhodamine which promote photocatalytic degradation). Prior