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

• contribution of the hydration shell in non-polar or aqueous solution. Time-resolved photoluminescence measurements showed that the photoluminescence dynamics of Au@MnO@SiO2-Atto495 Janus particles can be described by a bi-exponential decay progress. That is, it consists of two independent exponential decay

Nanobioarchitectures based on chlorophyll photopigment, artificial lipid bilayers and carbon nanotubes

• Marcela Elisabeta Barbinta-Patrascu,
• Stefan Marian Iordache,
• Ana Maria Iordache,
• Nicoleta Badea and
• Camelia Ungureanu

Beilstein J. Nanotechnol. 2014, 5, 2316–2325, doi:10.3762/bjnano.5.240

• (obtained by hydration of a dipalmitoyl phosphatidylcholine thin film) with and without cholesterol were labelled with a natural photopigment (chlorophyll a), which functioned as a sensor to detect modifications in the artificial lipid bilayers. These biomimetic membranes were used to build non-covalent

• composition: peptone (Merck, 10 g/L), yeast extract (Biolife, 5 g/L), NaCl (Sigma-Aldrich, 5 g/L) and agar (Fluka, 20 g/L). Synthesis Liposome preparation The hydration method [22] of a thin DPPC film was used to obtain two kinds of multilamellar lipid vesicles (MLVs, 0.5 mM) with and without cholesterol in

• bionanoarchitectures with interesting properties and potential applications in biomedical and biotechnological fields. Two types of biohybrids (with and without cholesterol) were developed starting with the chlorophyll-containing, artificial lipid bilayers prepared by hydration of a thin DPPC film. Chlorophyll a was

Sequence-dependent electrical response of ssDNA-decorated carbon nanotube, field-effect transistors to dopamine

• Hari Krishna Salila Vijayalal Mohan,
• Jianing An and
• Lianxi Zheng

Beilstein J. Nanotechnol. 2014, 5, 2113–2121, doi:10.3762/bjnano.5.220

• binding pockets within the proximity of the SWCNT sidewall. This hydrophilic environment on the SWCNT surface attracts polar analytes onto these hydration layers and solvates them, resulting in an increasing binding affinity of the polar analytes to these pockets. As more polar molecules are adsorbed, the

• DNA hydration layer, which is reflected as the decline in channel conductance (−∆Gon/Gon) [34]. The DA protonation results in electron transfer from the DNA to the SWCNT causing a change in the electrostatic environment around the nanotube, which is responsible for the observed shift in threshold

Effect of silver nanoparticles on human mesenchymal stem cell differentiation

• Christina Sengstock,
• Jörg Diendorf,
• Matthias Epple,
• Thomas A. Schildhauer and
• Manfred Köller

Beilstein J. Nanotechnol. 2014, 5, 2058–2069, doi:10.3762/bjnano.5.214

• . Note that the hydrodynamic diameter includes the polymer layer and the hydration shell and is therefore always larger than the pure metal diameter of the silver core as determined by electron microscopy under high vacuum. PVP (K30, Povidon 30; Fluka, molecular weight 40,000 g·mol−1), trisodium citrate

Effects of surface functionalization on the adsorption of human serum albumin onto nanoparticles – a fluorescence correlation spectroscopy study

• Pauline Maffre,
• Stefan Brandholt,
• Karin Nienhaus,
• Li Shang,
• Wolfgang J. Parak and
• G. Ulrich Nienhaus

Beilstein J. Nanotechnol. 2014, 5, 2036–2047, doi:10.3762/bjnano.5.212

• is the difference in hydrodynamic radius of NPs with and without protein corona. Consequently, the thickness change can only be attributed solely to the protein if the hydration layer contribution is equal for the bare and protein-bound NP surfaces. DPA–QDs are the only NPs with zwitterionic surface

• coatings in this data set, and they may have a more tightly bound, thicker hydration layer in the absence of protein. In fact, studies of the hydration layers on proteins, which have similar zwitterionic surfaces, suggest that these layers can extend out to 1 nm from the protein surface [52]. Another

In vitro and in vivo interactions of selected nanoparticles with rodent serum proteins and their consequences in biokinetics

• Wolfgang G. Kreyling,
• Stefanie Fertsch-Gapp,
• Martin Schäffler,
• Blair D. Johnston,
• Nadine Haberl,
• Christian Pfeiffer,
• Jörg Diendorf,
• Carsten Schleh,
• Stephanie Hirn,
• Manuela Semmler-Behnke,
• Matthias Epple and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1699–1711, doi:10.3762/bjnano.5.180

• with transmission electron microscopy (TEM), and does not take into account the hydration shell and adsorbed counter ions [6]. Selection of murine serum proteins bound to the differently sized AuNP after 24 h of incubation. A total of nine SDS gels per AuNP were investigated by using proteome analysis

Magnesium batteries: Current state of the art, issues and future perspectives

• Rana Mohtadi and
• Fuminori Mizuno

Beilstein J. Nanotechnol. 2014, 5, 1291–1311, doi:10.3762/bjnano.5.143

Model systems for studying cell adhesion and biomimetic actin networks

• Dorothea Brüggemann,
• Johannes P. Frohnmayer and
• Joachim P. Spatz

Beilstein J. Nanotechnol. 2014, 5, 1193–1202, doi:10.3762/bjnano.5.131

• incorporate biologically active proteins into GUVs. Gentle hydration of hybrid lipid-agarose films in solutions of cytoskeletal proteins yielded uniform actin and actomyosin networks enclosed in vesicles of 10 to 20 μm diameter (Figure 6) [72]. Actin filaments could also be specifically anchored to the GUV

Adsorption and oxidation of formaldehyde on a polycrystalline Pt film electrode: An in situ IR spectroscopy search for adsorbed reaction intermediates

• Zenonas Jusys and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2014, 5, 747–759, doi:10.3762/bjnano.5.87

• proceeding via adsorption of methylene glycol species, which are formed by hydration of formaldehyde in the solution phase [66][67]. Methylene glycol can be oxidized to adsorbed formates (formic acid) via a dehydrogenation step [6], without the need for OHad species. It is well known for methanol [4] and a

• species were possible via re-hydrogenation and subsequent desorption of the resulting adsorbed formaldehyde, re-hydrogenation of CDOad by protons (from water) should result in the formation of a mixed D1H1-formaldehyde. Its subsequent hydration to D1H1-methylene glycol and re-adsorption and oxidation to

Biocalcite, a multifunctional inorganic polymer: Building block for calcareous sponge spicules and bioseed for the synthesis of calcium phosphate-based bone

• Xiaohong Wang,
• Heinz C. Schröder and
• Werner E. G. Müller

Beilstein J. Nanotechnol. 2014, 5, 610–621, doi:10.3762/bjnano.5.72

• prevalent enzymes that allow bicarbonate to be formed in an organism are the carbonic anhydrases [CAs] [32]. These enzymes, which are characterized by an extremely high turnover number, catalyze the reversible hydration of carbon dioxide (CO2) to bicarbonate. This reaction occurs also in the presence of Ca

• . The closest human related CA to the Sycon enzyme (Figure 2C), the human CA-X (CAHA_HUMAN; Q9NS85), and -XI (CAHB_HUMAN; O75493), are grouped to the "acatalytic" CA isoforms of unknown function, which have been proposed to be devoid of CO2 hydration activity [39]. However, the branch with the two

• sponge CAs comprises a common origin with the stony coral Stylophora pistillata enzyme [40] for which an enzymatic activity has been proven. Those human CAes, comprising CO2 hydration activity (the catalytic CA), are in the CA group I to IV. The Zn-binding sites that are involved in the catalytic

Oriented attachment explains cobalt ferrite nanoparticle growth in bioinspired syntheses

• Annalena Wolff,
• Walid Hetaba,
• Marco Wißbrock,
• Stefan Löffler,
• Nadine Mill,
• Katrin Eckstädt,
• Axel Dreyer,
• Inga Ennen,
• Norbert Sewald,
• Peter Schattschneider and
• Andreas Hütten

Beilstein J. Nanotechnol. 2014, 5, 210–218, doi:10.3762/bjnano.5.23

• -attraction and repulsive forces due to c25-mms6 or hydration layers, are most likely the dominating factors in this process since the small substructures possess diameters below the superparamagnetic limit [9][11]. During the assembly, crystallites grow and form the subunits referred to as primary building

Peak forces and lateral resolution in amplitude modulation force microscopy in liquid

• Horacio V. Guzman and
• Ricardo Garcia

Beilstein J. Nanotechnol. 2013, 4, 852–859, doi:10.3762/bjnano.4.96

• resolution that the result given by Hertz model. The results presented here provide a good estimation of the peak force values experienced by the samples observed with an AFM in liquid. However, the simulations have been performed without considering hydration layers or viscoelastic effects that arise either

• from the sample or the hydration layer. Those effects could modify the peak force values reported here, although we do not expect significant changes for the data acquired under the conditions for a high spatial resolution (sub-5 nm). Peak forces, tip motion and contact time for two materials. (a) Soft

Large-scale atomistic and quantum-mechanical simulations of a Nafion membrane: Morphology, proton solvation and charge transport

• Pavel V. Komarov,
• Pavel G. Khalatur and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 567–587, doi:10.3762/bjnano.4.65

• + responsible for charge transfer reactions. The hydration level, [H2O]/[SO3H], is defined as the ratio of the number of water molecules to the number of sulfonated groups: λ = nw/nsnc. The value of λ was 5, 10, and 20. Note that the hydration level λ = 5 is close to the percolation threshold value for water

• molecules in a Nafion membrane [38][48], while λ = 10 and 20 is close to the operating regime. At these hydration levels, the membrane may function as a proton-conducting material [61][62][63]. One should keep in mind that the range of λ values corresponding to the specified hydration regime (low or high

• hydration conditions) depends on the ratio of hydrophobic/hydrophilic segments in a polymer chain [53]. That is why under certain conditions the state with λ = 10 and 20 can be referred to the high hydration level. For the systems under study, both λ values correspond to high acidities (pH<<1). Thus, the

Growth behaviour and mechanical properties of PLL/HA multilayer films studied by AFM

• Cagri Üzüm,
• Johannes Hellwig,
• Narayanan Madaboosi,
• Dmitry Volodkin and
• Regine von Klitzing

Beilstein J. Nanotechnol. 2012, 3, 778–788, doi:10.3762/bjnano.3.87

• the film bilayer number n. This result contradicts the results of Richert et al. [4], who reported a decrease in E from 90 kPa for n = 20 to 40 kPa for n = 60. The authors suggested a possibility of film softening due to greater hydration of the upper layers rather than due to a change in surface

Pulse-response measurement of frequency-resolved water dynamics on a hydrophilic surface using a Q-damped atomic force microscopy cantilever

• Masami Kageshima

Beilstein J. Nanotechnol. 2012, 3, 260–266, doi:10.3762/bjnano.3.29

• Masami Kageshima Department of Physics, Tokyo Gakugei University, 4-1-1 Nukui-kita-machi, Koganei, Tokyo 184-8501, Japan 10.3762/bjnano.3.29 Abstract The frequency-resolved viscoelasticity of a hydration layer on a mica surface was studied by pulse-response measurement of a magnetically driven

• –sample system. The significant viscoelasticity spectrum of the hydration layer was successfully derived in a frequency range below 100 kHz by comparison of data obtained at a distance of 300 nm from the substrate with those taken in the proximity of the substrate. A positive value of the real part of the

• stiffness was determined and is attributed to the reported solidification of the hydration layers. Keywords: atomic force microscopy; hydration; pulse-response; quality-factor control; viscoelasticity; Introduction Liquid solvation is a phenomenon common to a large variety of liquid–solid interfaces [1

Parallel- and serial-contact electrochemical metallization of monolayer nanopatterns: A versatile synthetic tool en route to bottom-up assembly of electric nanocircuits

• Jonathan Berson,
• Assaf Zeira,
• Rivka Maoz and
• Jacob Sagiv

Beilstein J. Nanotechnol. 2012, 3, 134–143, doi:10.3762/bjnano.3.14

• ) sites of nondestructively patterned OTS/Si monolayers demonstrates that metal ions have to shed their hydration shell and reach the electrode surface before being discharged, rather than being first reduced to neutral atoms by electron transfer to hydrated ionic species in solution [54][55