A facile method for the preparation of bifunctional Mn:ZnS/ZnS/Fe₃O₄ magnetic and fluorescent nanocrystals

• Houcine Labiadh,
• Tahar Ben Chaabane,
• Romain Sibille,
• Lavinia Balan and
• Raphaël Schneider

Beilstein J. Nanotechnol. 2015, 6, 1743–1751, doi:10.3762/bjnano.6.178

• heterostructures were characterized by X-ray diffraction (XRD), dynamic light scattering (DLS), transmission electron microscopy (TEM), UV–vis spectroscopy and photoluminescence (PL) spectroscopy. The PL spectra of Mn:ZnS/ZnS/Fe3O4 quantum dots (QDs) showed marked visible emission around 584 nm related to the 4T1

• properties of the composites. Nevertheless, a good compromise was achieved in order to maintain the dual modality of the nanocrystals, which may be promising candidates for various biological applications. Keywords: aqueous synthesis; bifunctional nanocrystals; magnetite; Mn-doped ZnS; quantum dots

• ; Introduction Semiconductor nanocrystals with a diameter of approximately 1–10 nm, also referred to as quantum dots (QDs), have attracted great attention due to their unique optical and electronic properties, which are not observed in bulk semiconductor materials [1][2][3]. Compared to conventional organic dyes

Analysis of soil bacteria susceptibility to manufactured nanoparticles via data visualization

• Rong Liu,
• Yuan Ge,
• Patricia A. Holden and
• Yoram Cohen

Beilstein J. Nanotechnol. 2015, 6, 1635–1651, doi:10.3762/bjnano.6.166

• communities [18][19]; quantum dots (QDs) were linked to DNA damage of both freshwater mussels and gills [24]; and carbon nanotubes have been found to induce harmful effects to various organs (such as aquatic animals, bacteria, and plants) [25]. MNPs in soil can cause compositional changes to soil bacterial

Molecular materials – towards quantum properties

• Mario Ruben

Beilstein J. Nanotechnol. 2015, 6, 1485–1486, doi:10.3762/bjnano.6.153

• information schemes. As a result of their confinement, electrons in both natural atoms and in quantum dots, so-called artificial atoms, are characterized by the formation of discrete energy levels. Similarly, in the case of a Josephson junction, Cooper pairs are confined in the potential well of the Josephson

Self-assembly of nanostructures and nanomaterials

• Isabelle Berbezier and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2015, 6, 1397–1398, doi:10.3762/bjnano.6.144

• , quantum properties and applications of nanoscale assemblies to advanced devices. The main topics of interest involve 2D nanomaterials such as nanomembranes, graphene, silicene and ordered mesoporous oxides, 1D nanomaterials such as nanowires and nanotubes, and 0D nanomaterials such as quantum dots

PLGA nanoparticles as a platform for vitamin D-based cancer therapy

• Maria J. Ramalho,
• Joana A. Loureiro,
• Bárbara Gomes,
• Manuela F. Frasco,
• Manuel A. N. Coelho and
• M. Carmo Pereira

Beilstein J. Nanotechnol. 2015, 6, 1306–1318, doi:10.3762/bjnano.6.135

• inhibition when compared to free calcidiol, and the PLA NPs enhanced the intracellular delivery of vitamin in breast cancer cells [14]. In another work, Bonor et al. [23] developed calcitriol-conjugated quantum dots to analyze calcitriol distribution and dynamics in mouse myoblast cells. The authors

Addition of Zn during the phosphine-based synthesis of indium phospide quantum dots: doping and surface passivation

• Natalia E. Mordvinova,
• Alexander A. Vinokurov,
• Oleg I. Lebedev,
• Tatiana A. Kuznetsova and
• Sergey G. Dorofeev

Beilstein J. Nanotechnol. 2015, 6, 1237–1246, doi:10.3762/bjnano.6.127

• 10.3762/bjnano.6.127 Abstract Zinc-doped InP(Zn) colloidal quantum dots (QDs) with narrow size distribution and low defect concentration were grown for the first time via a novel phosphine synthetic route and over a wide range of Zn doping. We report the influence of Zn on the optical properties of the

• obtained quantum dots. We propose a mechanism for the introduction of Zn in the QDs and show that the incorporation of Zn atoms into the InP lattice leads to the formation of Zn acceptor levels and a luminescence tail in the red region of the spectra. Using photochemical etching with HF, we confirmed that

• luminescence quantum yield through the reduction of phosphorous dangling bonds. A scenario for the growth of the colloidal InP(Zn) QDs was proposed and discussed. Keywords: core–shell nanoparticles; doped semiconductor nanocrystals; InP(Zn) quantum dots; luminescence; zinc; Introduction Colloidal quantum

Tattoo ink nanoparticles in skin tissue and fibroblasts

• Colin A. Grant,
• Peter C. Twigg,
• Richard Baker and
• Desmond J. Tobin

Beilstein J. Nanotechnol. 2015, 6, 1183–1191, doi:10.3762/bjnano.6.120

• quantum dots and nanocrystals to target specific tumour antigens [6]. Other medical research on nanoparticles includes the formation of a network of nanoparticles with an insulin core that can regulate and control normal blood sugar level [7]. However, despite considerable progress in nanoscience, it is

Protein corona – from molecular adsorption to physiological complexity

• Lennart Treuel,
• Dominic Docter,
• Michael Maskos and
• Roland H. Stauber

Beilstein J. Nanotechnol. 2015, 6, 857–873, doi:10.3762/bjnano.6.88

• acid (DHLA)-coated quantum dots (QDs) by using fluorescence correlation spectroscopy (FCS) [4]. The electrostatic surface potential of native HSA shows distinct, positively charged patches on an otherwise negative potential surface (Figure 3). These patches are caused by the presence of basic lysine

• American Chemical Society. Binding curves as determined by fluorescence correlation spectroscopy and schematic representations for adsorption of (a and b) HSA, (c and d) HSAsuc and (e and f) HSAam onto dihydrolipoic acid-coated quantum dots. Filled symbols: Hydrodynamic radii of DHLA-QDs plotted as a

Statistics of work and orthogonality catastrophe in discrete level systems: an application to fullerene molecules and ultra-cold trapped Fermi gases

• Antonello Sindona,
• Michele Pisarra,
• Mario Gravina,
• Cristian Vacacela Gomez,
• Pierfrancesco Riccardi,
• Giovanni Falcone and
• Francesco Plastina

Beilstein J. Nanotechnol. 2015, 6, 755–766, doi:10.3762/bjnano.6.78

• absorption and emission spectra from noninteracting quantum dots have been interpreted in terms of the quantum work distribution, and linked to the corresponding fluctuation relations in statistical mechanics [36]. To explore more of such a connection, we present here a comparison of the statistics of the

Observation of a photoinduced, resonant tunneling effect in a carbon nanotube–silicon heterojunction

• Carla Aramo,
• Antonio Ambrosio,
• Michelangelo Ambrosio,
• Maurizio Boscardin,
• Paola Castrucci,
• Michele Crivellari,
• Marco Cilmo,
• Maurizio De Crescenzi,
• Francesco De Nicola,
• Emanuele Fiandrini,
• Valentina Grossi,
• Pasqualino Maddalena,
• Maurizio Passacantando,
• Sandro Santucci,
• Manuela Scarselli and
• Antonio Valentini

Beilstein J. Nanotechnol. 2015, 6, 704–710, doi:10.3762/bjnano.6.71

• structures (e.g., heavily doped p–n junction, double and triple barrier, quantum well, quantum wires and quantum dots, nanotubes and graphene) [1][2][3][4][5][6][7]. In general, it has been associated with the occurrence of a process at the junction that allows the electrons to tunnel between energy levels

Influence of gold, silver and gold–silver alloy nanoparticles on germ cell function and embryo development

• Ulrike Taylor,
• Daniela Tiedemann,
• Christoph Rehbock,
• Wilfried A. Kues,
• Stephan Barcikowski and
• Detlef Rath

Beilstein J. Nanotechnol. 2015, 6, 651–664, doi:10.3762/bjnano.6.66

• , PVP–Eu(OH)3 NP, PVA–Eu(OH)3 [65] and bio-conjugated CdSe/ZnS quantum dots [66] into spermatozoa has been reported. However, the picture evidence provided to support these claims does not withstand critical examination at least with regard to intact, non-acrosome reacted spermatozoa, which are the ones

• and collegues examined the effect of titanium dioxide nanoparticles on isolated preantral rat follicles in vitro [75], while Hsieh et al. studied the cytotoxicity of CdSe quantum dots on the maturation of mouse oocytes, fertilization, and fetal development [76]. Both studies reported detrimental

Silica micro/nanospheres for theranostics: from bimodal MRI and fluorescent imaging probes to cancer therapy

• Shanka Walia and
• Amitabha Acharya

Beilstein J. Nanotechnol. 2015, 6, 546–558, doi:10.3762/bjnano.6.57

• ; organic dyes; quantum dots; silica nanospheres; theranostics; Review 1 Introduction In the modern era of medical diagnosis, X-rays have long played a major role in the clinical imaging of anatomical details of disease sites [1]. However, the development of suitable molecular diagnostic systems for

• NPs can be maximized. In our earlier review, we have compiled the literature reports on the biological studies of the hybrid nanocomposite materials, exclusively composed of luminescent quantum dots (QDs) and magnetically active iron oxide as bimodal imaging agents [2]. In this sense, nanostructured

• (TMAH). Finally, bioconjugation on silica surface of the magnetic NPs and quantum dots was accomplished by using oleyl-O-poly(ethylene glycol)succinyl-N-hydroxysuccinimidyl ester. The characterization of these NPs was done by using UV–vis and fluorescence spectroscopy, HRTEM, STEM and SQUID studies. The

Biological responses to nanoscale particles

• Reinhard Zellner

Beilstein J. Nanotechnol. 2015, 6, 380–382, doi:10.3762/bjnano.6.37

• used in this study were those of current, wide-spread technological importance, such as metals (e.g., silver, gold, platinum), oxides (e.g., silica, iron oxide, cerium oxide, manganese oxide), polymers (e.g., polystyrene) and quantum dots (II/VI semiconductors). Naturally occurring and industrially

Nanoparticle shapes by using Wulff constructions and first-principles calculations

• Georgios D. Barmparis,
• Zbigniew Lodziana,
• Nuria Lopez and
• Ioannis N. Remediakis

Beilstein J. Nanotechnol. 2015, 6, 361–368, doi:10.3762/bjnano.6.35

• implementations are Wulffman [19] and VESTA [20]. Among the first uses of the Wulff construction for the characterization of nanoparticles are experiments by H. Topsøe and co-workers for Cu-based catalysts [21][22], and the theory of Müller and Kern for epitaxially strained semiconductor quantum dots [23]. Since

Comparative evaluation of the impact on endothelial cells induced by different nanoparticle structures and functionalization

• Lisa Landgraf,
• Ines Müller,
• Peter Ernst,
• Miriam Schäfer,
• Christina Rosman,
• Isabel Schick,
• Oskar Köhler,
• Hartmut Oehring,
• Vladimir V. Breus,
• Thomas Basché,
• Carsten Sönnichsen,
• Wolfgang Tremel and
• Ingrid Hilger

Beilstein J. Nanotechnol. 2015, 6, 300–312, doi:10.3762/bjnano.6.28

• nanoparticles on endothelial cells. Our findings will help to design new nanoparticles with optimized properties concerning biocompatibility and uptake behavior with respect to the respective intended application. Keywords: cell viability; gold nanoparticles; internalization; Janus particles; quantum dots

• . Colloidal semiconductor nanocrystals or quantum dots (QDs) with their outstanding fluorescence properties also play a distinct role in life science. QDs exhibit high stability against photo bleaching and they are easily tunable in color. Several studies demonstrated their feasibility for detection of

• Fe3O4) and quantum dots (QDs). 1) Gold nanoparticles (GNP): The gold colloids with a core size of approximately 40 nm in diameter were synthesized according to Rosman et al. [45] and were spherically or rod-like shaped. GNP without surface functionalization were transferred to 0.1 M

The effect of surface charge on nonspecific uptake and cytotoxicity of CdSe/ZnS core/shell quantum dots

• Vladimir V. Breus,
• Anna Pietuch,
• Marco Tarantola,
• Thomas Basché and
• Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 281–292, doi:10.3762/bjnano.6.26

• -particle tracking), was shown to compromise the integrity of the cytoskeletal and plasma membrane dynamics, as evidenced by electric cell–substrate impedance sensing. Keywords: biocompatibility; CdSe/ZnS; cytotoxicity; ECIS; quantum dots; single-particle tracking; Introduction Quantum dots (QDs) are

• core synthesis The synthesis of the CdSe core of the quantum dots and the ZnS shell followed a modified prescription from Mahler et al. [47] The Se injection solution was prepared by heating 64 mg of Se, 4 mL of trioctylphosphine, 1.5 mL of oleylamine and 1 g of tetradecylphosphonic acid under argon

• -Planck-Institute for Dynamics and Self-Organization (MPIDS), Laboratory for Fluid Dynamics, Pattern Formation and Biocomplexity, Am Fassberg 17, 37077 Goettingen, Germany 10.3762/bjnano.6.26 Abstract In this work, cytotoxicity and cellular impedance response was compared for CdSe/ZnS core/shell quantum

Overview about the localization of nanoparticles in tissue and cellular context by different imaging techniques

• Anja Ostrowski,
• Daniel Nordmeyer,
• Alexander Boreham,
• Cornelia Holzhausen,
• Lars Mundhenk,
• Christina Graf,
• Martina C. Meinke,
• Annika Vogt,
• Sabrina Hadam,
• Jürgen Lademann,
• Eckart Rühl,
• Ulrike Alexiev and
• Achim D. Gruber

Beilstein J. Nanotechnol. 2015, 6, 263–280, doi:10.3762/bjnano.6.25

• ]. In this regard, the increased brightness and photostability of a fluorescent dye when incorporated into the core of SiO2-NP are particularly welcome [83]. Of note, some specifically engineered NP may hold inherent fluorescent properties, such as inorganic quantum dots (QD) [76]. QD used in

Tailoring the ligand shell for the control of cellular uptake and optical properties of nanocrystals

• Johannes Ostermann,
• Christian Schmidtke,
• Christopher Wolter,
• Jan-Philip Merkl,
• Hauke Kloust and
• Horst Weller

Beilstein J. Nanotechnol. 2015, 6, 232–242, doi:10.3762/bjnano.6.22

• and specificity in a broad in vitro test is demonstrated. Keywords: biolable; cellular uptake; fluorescence quenching; poylmeric micelles; quantum dots; Introduction One of the main challenges in using high quality nanoparticles for biological applications is to ensure that the ligand system

• has shown to drastically enhance the fluorescence properties, namely the fluorescence quantum efficiency, of encapsulated CdSe/CdS/ZnS and CdSe/CdxZn(1-x)S/ZnS core–shell–shell quantum dots (QDs). This enhancement can be explained to a certain extent by the cross-linking of the micelles but further

Caveolin-1 and CDC42 mediated endocytosis of silica-coated iron oxide nanoparticles in HeLa cells

• Nils Bohmer and
• Andreas Jordan

Beilstein J. Nanotechnol. 2015, 6, 167–176, doi:10.3762/bjnano.6.16

• was chosen as a model cell line. Hela cells are a well-established malignant cell line, which was widely used to study the uptake of iron oxide nanoparticles [18][21][24][32], gold nanoparticles [33][34] and other particle systems like quantum dots [35] or polymer particles [36][37]. To gain insights

• human alveolar epithelial cells and polystyrene nanoparticles around 100 nm [38] as well as polymer coated gold nanoparticles with a core size around 13 nm [39]. On the other hand there are studies showing the uptake of different nanoparticles by HeLa cells such as quantum dots [35], PEG-PLA particles

The distribution and degradation of radiolabeled superparamagnetic iron oxide nanoparticles and quantum dots in mice

• Denise Bargheer,
• Artur Giemsa,
• Barbara Freund,
• Markus Heine,
• Christian Waurisch,
• Gordon M. Stachowski,
• Stephen G. Hickey,
• Alexander Eychmüller,
• Jörg Heeren and
• Peter Nielsen

Beilstein J. Nanotechnol. 2015, 6, 111–123, doi:10.3762/bjnano.6.11

• , Germany Institute of Physical Chemistry and Electrochemistry, Technical University of Dresden, Bergstr. 66b, 01069 Dresden, Germany 10.3762/bjnano.6.11 Abstract 51Cr-labeled, superparamagnetic, iron oxide nanoparticles (51Cr-SPIOs) and 65Zn-labeled CdSe/CdS/ZnS-quantum dots (65Zn-Qdots) were prepared

• /CdS/ZnS-Qdots in the liver. Keywords: biodistribution; chromium(III); 51Cr; quantum dots; SPIOs; zinc metabolism; 65Zn; Introduction Quantum dots (Qdots) are semiconductor nanocrystals (2–100 nm in diameter) that combine a strong, size-tunable photoluminescence with robust photostability, which

• the iron oxide core of SPIOs under similar experimental conditions was unsuccessful. However, a distinct incorporation of 65ZnCl2 occurred when CdSe/CdS/ZnS core/shell/shell quantum dots were synthesized (Figure 1). Both hydrophobic nanoparticle cores were encapsulated using the same polymer to render

Synthesis of boron nitride nanotubes and their applications

• Saban Kalay,
• Zehra Yilmaz,
• Ozlem Sen,
• Melis Emanet,
• Emine Kazanc and
• Mustafa Çulha

Beilstein J. Nanotechnol. 2015, 6, 84–102, doi:10.3762/bjnano.6.9

• amino groups and its use as a good dispersion agent [79]. The BNNTs were first coated with PLL and then with quantum dots (QDs) to observe the cellular uptake of PLL–BNNTs in C2C12 mouse myoblast cells. To observe the energy dependence of the uptake mechanism of the PLL–BNNTs, sodium azide was used to

• carriers of boron atoms. Figure 9 shows how the BNNTs were functionalized with PLL, a fluorescent probe (quantum dots) and folic acids. PLLs were wrapped around the BNNTs to induce a hydrophilic property. In addition, the BNNTs were coated with folic acids for selective interaction with the tumor cells

The fate of a designed protein corona on nanoparticles in vitro and in vivo

• Denise Bargheer,
• Julius Nielsen,
• Gabriella Gébel,
• Markus Heine,
• Sunhild C. Salmen,
• Roland Stauber,
• Horst Weller,
• Joerg Heeren and
• Peter Nielsen

Beilstein J. Nanotechnol. 2015, 6, 36–46, doi:10.3762/bjnano.6.5

• resulted in a more neutral particle (B), reaction with PEG-bisamine in an even cationic particle (C) as seen in electrophoresis (left Quantum dots, right SPIOs with the same polymer-coating and the same pegylation). Modification of the EDC concentration resulted in gradually PEGylated products, which can

Nanoparticle interactions with live cells: Quantitative fluorescence microscopy of nanoparticle size effects

• Li Shang,
• Karin Nienhaus,
• Xiue Jiang,
• Linxiao Yang,
• Katharina Landfester,
• Volker Mailänder,
• Thomas Simmet and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2014, 5, 2388–2397, doi:10.3762/bjnano.5.248

• with widely differing sizes. We have selected very small gold nanoclusters (AuNCs, diameter ≈3 nm) stabilized with dihydrolipoic acid (DHLA), semiconductor core-shell quantum dots (CdSe/ZnS, ≈10 nm) coated with D-penicillamine (DPA) and relatively large polystyrene (PS) NPs (≈100 nm) with different

• , some general conclusions are drawn as to how the NP size affects the mechanistic details of the uptake process. Results and Discussion NP characterization We have synthesized differently sized, water-soluble NPs, including intrinsically luminescent D-penicillamine-coated quantum dots (DPA-QDs) [28

Synthesis of radioactively labelled CdSe/CdS/ZnS quantum dots for in vivo experiments

• Gordon M. Stachowski,
• Christoph Bauer,
• Christian Waurisch,
• Denise Bargheer,
• Peter Nielsen,
• Jörg Heeren,
• Stephen G. Hickey and
• Alexander Eychmüller

Beilstein J. Nanotechnol. 2014, 5, 2383–2387, doi:10.3762/bjnano.5.247

• nanomaterials have been developed for applications in the field of bio-labelling. For the visualization of transport processes in the body, organs and cells, luminescent quantum dots (QDs) make for highly useful diagnostic tools. However, intercellular routes, bio-distribution, metabolism during degradation or

• phase transfer of the QDs. Keywords: biomarker; CdSe/CdS/ZnS; quantum dots; radioactive labelling; 65Zn; Introduction Two decades of research and investigation in the field of luminescent semiconductor nanoparticles, also known as quantum dots (QDs), have now passed since the fundamental work of

Inorganic Janus particles for biomedical applications

• Isabel Schick,
• Steffen Lorenz,
• Dominik Gehrig,
• Stefan Tenzer,
• Wiebke Storck,
• Karl Fischer,
• Dennis Strand,
• Frédéric Laquai and
• Wolfgang Tremel

Beilstein J. Nanotechnol. 2014, 5, 2346–2362, doi:10.3762/bjnano.5.244

• properties [16][17]. Since the 1980s [16][18][19], there has been a huge research effort in optimizing the characteristics of hetero-structured semiconductors with extraordinary optical properties. Xie et al. [13] demonstrated the design of CdSe quantum dots covered by a multishell structure from CdS and ZnS

• yield governed by the electronic passivation of the surface, whereas the quantum yield was decreased for a shell thickness of more than two multilayers, which was attributed to lattice imperfections within the shell (Figure 2c) [13]. Recent developments in the fields of hetero-structured quantum dots

• exploration of their physicochemical properties and large scale applications in the near future. Illustrations of the transition from isotropic to anisotropic particles. a) Evolution of the PL-peak position, b) schematic representation, and c) evolution of the PL-quantum yield for several core-shell quantum