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

• electrostatic forces due to the PLGA carboxylate groups at the NP surface, and the surfactant behavior that also plays a crucial role in maintaining nanosuspension stabilization. During particle formation, the Pluronic®F127 is adsorbed onto the NP surface, providing steric and thermodynamic stabilization

Improved optical limiting performance of laser-ablation-generated metal nanoparticles due to silica-microsphere-induced local field enhancement

• Zheren Du,
• Lianwei Chen,
• Tsung-Sheng Kao,
• Mengxue Wu and
• Minghui Hong

Beilstein J. Nanotechnol. 2015, 6, 1199–1204, doi:10.3762/bjnano.6.122

• duration, and laser fluence) and the properties of the environment (e.g., surfactant concentration, pH value, or size and length of ligands) [1][2][3][4][5][6]. Laser ablation is an explosive material removal process using strong pulsed-laser irradiation. The LAL process causes the ejection of nanoclusters

A simple approach to the synthesis of Cu_1.8S dendrites with thiamine hydrochloride as a sulfur source and structure-directing agent

• Xiaoliang Yan,
• Sha Li,
• Yun-xiang Pan,
• Zhi Yang and
• Xuguang Liu

Beilstein J. Nanotechnol. 2015, 6, 881–885, doi:10.3762/bjnano.6.90

• nitrate and thiamine hydrochloride were selected as the starting materials in the water phase under hydrothermal conditions. No addition of a surfactant or a complex reagent was required for the synthesis of the Cu1.8S dendrite structures. Thiamine hydrochloride was employed as a sulfur source and

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

• trimethylammonium bromide (CTAB), butanol and hexane as surfactant, co-surfactant and oil phase, respectively. The silica coating of the Gd2(CO3)3:Tb complex was done by using tetraethylorthosilicate (TEOS) under ammonical conditions. The synthesized NPs were characterized by HRTEM, EDX and FTIR. The size of the

• synthesis was enhanced by using Y(NO3)3·6H2O and Eu2O3 as reactants, CTAB as surfactant and TEOS as alkyl silicate. Finally, the anticancer drug doxyrubicin (DOX) was loaded into the prepared NPs. Characterization of mesoporous silica NPs (MSN), YVO4:Eu3+ NPs and YVO4-MSNs were done by XRD, FTIR, TEM and

• -shell-encapsulated hybrid nanomaterials consisting of paramagnetic Gd3+ ions and QDs or Au nanocrystals. The citric-acid-capped gold colloids and CdSe/ZnS QDs were silanized by using mercaptopropyltrimethoxysilane (MPS) as surfactant. Further, a Gd3+-DOTA (tetraazacyclododecanetetraacetic acid) complex

Pulmonary surfactant augments cytotoxicity of silica nanoparticles: Studies on an in vitro air–blood barrier model

• Jennifer Y. Kasper,
• Lisa Feiden,
• Maria I. Hermanns,
• Christoph Bantz,
• Michael Maskos,
• Ronald E. Unger and
• C. James Kirkpatrick

Beilstein J. Nanotechnol. 2015, 6, 517–528, doi:10.3762/bjnano.6.54

• to investigate the potential hazard of NPs. However, in most in vitro studies a crucial alveolar component has been neglected. Before aspirated NPs encounter the cellular air–blood barrier, they impinge on the alveolar surfactant layer (10–20 nm in thickness) that lines the entire alveolar surface

• . Thus, a prior interaction of NPs with pulmonary surfactant components will occur. In the present study we explored the impact of pulmonary surfactant on the cytotoxic potential of amorphous silica nanoparticles (aSNPs) using in vitro mono- and complex coculture models of the air–blood barrier

• . Furthermore, different surface functionalisations (plain-unmodified, amino, carboxylate) of the aSNPs were compared in order to study the impact of chemical surface properties on aSNP cytotoxicity in combination with lung surfactant. The alveolar epithelial cell line A549 was used in mono- and in coculture

Conformal SiO₂ coating of sub-100 nm diameter channels of polycarbonate etched ion-track channels by atomic layer deposition

• Nicolas Sobel,
• Christian Hess,
• Manuela Lukas,
• Anne Spende,
• Bernd Stühn,
• M. E. Toimil-Molares and
• Christina Trautmann

Beilstein J. Nanotechnol. 2015, 6, 472–479, doi:10.3762/bjnano.6.48

• narrow size distribution [4][5][6]. Typically, polymers such as polycarbonate (PC), polyethylene terephthalate, and polyimide are employed as templates. Hydrophilicity is sometimes improved by immersing the etched membrane in a surfactant solution such as polyvinylpyrrolidone. The addition of surfactants

Hematopoietic and mesenchymal stem cells: polymeric nanoparticle uptake and lineage differentiation

• Ivonne Brüstle,
• Thomas Simmet,
• Gerd Ulrich Nienhaus,
• Katharina Landfester and
• Volker Mailänder

Beilstein J. Nanotechnol. 2015, 6, 383–395, doi:10.3762/bjnano.6.38

• functionalized polystyrene nanoparticles as described in [18]) or by a combination of miniemulsion and emulsion/solvent evaporation techniques (PLLA nanoparticles without and with magnetite, as described in [19][20]). In all cases, SDS was used as a surfactant for the synthesis or formation of the nanoparticles

• . The nanoparticles were purified from the surfactant excess by dialysis using Amicon Ultra membrane filters with MWCO 100 kDa (Millipore). The main characteristics of the nanoparticles are described in Table 1. Uptake and toxicity of polymeric nanoparticles Before the nanoparticles were used for

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

• ). Right: With adsorbed SCH3 radicals (29 nm in diameter, 502900 atoms, 10600 of which are step-edge atoms; (211) faces occupy almost 100% of the total area). Schematic representation of the adsorption of a surfactant on a gold surface. Spheres represent gold (yellow), silver (grey) and bromine (red) and

• the tails of the surfactant are represented by sticks. Wulff construction for the nanoparticles of LiBH4. The blue spheres are for lithium, red for boron and white are hydrogen atoms. Acknowledgements INR acknowledges valuable discussions on Wulff construction with Prof. Phoebus Rosakis. ZL

Exploiting the hierarchical morphology of single-walled and multi-walled carbon nanotube films for highly hydrophobic coatings

• Francesco De Nicola,
• Paola Castrucci,
• Manuela Scarselli,
• Francesca Nanni,
• Ilaria Cacciotti and
• Maurizio De Crescenzi

Beilstein J. Nanotechnol. 2015, 6, 353–360, doi:10.3762/bjnano.6.34

• , assay >90%, diameter: 5–50 nm) were dispersed in aqueous solution (80 μg·mL−1) with 2% w/v sodium dodecyl sulfate (Sigma-Aldrich, assay >98.5%) anionic surfactant. In addition, to better disperse the suspension, the carbon nanotubes were tip-ultrasonicated (Branson S250A, 200 W, 20% power, 20 kHz) in an

• two different film layers were obtained. Subsequently, rinsing in water and in a solution of ethanol, methanol and water (15:15:70) to remove as much surfactant as possible was performed. Samples were made uniformly depositing by the dry-transfer printing method carbon nanotube films on Carlo Erba

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

• assess the toxicity of the BNNTs. Similar to CNTs, one of the major problems in toxicity assessment of BNNTs is their low dispersibility in aqueous media, due to their high hydrophobicity. In order to increase the dispersion, either a surfactant or hydrophilic polymer is used to alter the surface

Mammalian cell growth on gold nanoparticle-decorated substrates is influenced by the nanoparticle coating

• Christina Rosman,
• Sebastien Pierrat,
• Marco Tarantola,
• David Schneider,
• Eva Sunnick,
• Andreas Janshoff and
• Carsten Sönnichsen

Beilstein J. Nanotechnol. 2014, 5, 2479–2488, doi:10.3762/bjnano.5.257

• Planck Institute for Biology of Ageing, Joseph-Stelzmann-Straße 9b, 50931 Cologne, Germany 10.3762/bjnano.5.257 Abstract In this work, we study epithelial cell growth on substrates decorated with gold nanorods that are functionalized either with a positively charged cytotoxic surfactant or with a

• cell migration and no significant particle internalization occurred. Concerning cell adhesion and spreading as compared to cell growth on bare substrates after 3 days of incubation, a reduction by 45% and 95%, respectively, for the surfactant particle coating was observed, whereas the amino-terminated

• decorated with various amounts of surfactant-coated particles. A surface density of 65 particles/µm2 (which corresponds to 0.5% of surface coverage with nanoparticles) diminishes micromotion by 25% as compared to bare substrates after 35 hours of incubation. We conclude that the surface coating of the gold

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

• adsorbed amphiphiles, the anionic surfactant SDS or cetyltrimethylammonium (CTMA) chloride to yield negatively (PS−) and positively (PS+) charged NPs, respectively. The hydrodynamic diameters of these NPs suspended in PBS, pH 7.4, were determined by dynamic light scattering (DLS) (Table 1). Furthermore

Si/Ge intermixing during Ge Stranski–Krastanov growth

• Alain Portavoce,
• Khalid Hoummada,
• Antoine Ronda,
• Dominique Mangelinck and
• Isabelle Berbezier

Beilstein J. Nanotechnol. 2014, 5, 2374–2382, doi:10.3762/bjnano.5.246

• dot assembly [1][2][3][4][5][6][7]. The focus of these investigations was devoted to understanding the shape of the islands and density variations versus stress (or strain) or substrate surface modifications (e.g., patterning, Si(Ge) buffer or surfactant variations) [6][7][8][9][10][11], using

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

• nanoparticles [75][76][77]. Inspired by the idea of the formation of a complex composed of the metal ion and the ligand, the strategy of direct employment of a metal-surfactant complex was used. For instance, manganese(II)oleate [77] and iron(III)oleate [64][75][78] can be handled easily and safely due to their

• permission from [29]. Copyright 2008 The Royal Society of Chemistry. (a) Schematic representation of bimetallic Janus particles at the hexane–water interface (gold: gold part with surfactant; gray: iron oxide part). (b) Interfacial tension vs time as measured by pendant drop tensiometry (NP: homogeneous

Liquid-phase exfoliated graphene: functionalization, characterization, and applications

• Mildred Quintana,
• Jesús Iván Tapia and
• Maurizio Prato

Beilstein J. Nanotechnol. 2014, 5, 2328–2338, doi:10.3762/bjnano.5.242

• the production of highly reactive chemical species including peroxides and radicals formed from the sonochemical reaction of the solvent in air [20]. The combined mechanochemical effects of ultrasonication prompt the exfoliation of graphite in organic solvents, surfactant solutions, or mixed organic

• the square of the zeta potential of the surfactant-coated sheets. This means that the concentration is proportional to the magnitude of the electrostatic potential barrier, which prevents graphene π–π stabilization. In contrast, for non-ionic surfactants, the dispersed graphene concentration increased

Characterization of 10,12-pentacosadiynoic acid Langmuir–Blodgett monolayers and their use in metal–insulator–metal tunnel devices

• Saumya Sharma,
• Mohamad Khawaja,
• Manoj K. Ram,
• D. Yogi Goswami and
• Elias Stefanakos

Beilstein J. Nanotechnol. 2014, 5, 2240–2247, doi:10.3762/bjnano.5.233

• MIM structures. Experimental Overview of the deposition of PDA, LS films Langmuir monolayers and LB films: For these experiments, PDA was obtained from Sigma-Aldrich in the form of 10,12-pentacosadiynoic acid (≥97.0%, HPLC grade). A 0.2 mg/mL solution of the surfactant PDA was prepared in chloroform

Hybrid spin-crossover nanostructures

• Carlos M. Quintero,
• Gautier Félix,
• Iurii Suleimanov,
• José Sánchez Costa,
• Gábor Molnár,
• Lionel Salmon,
• William Nicolazzi and
• Azzedine Bousseksou

Beilstein J. Nanotechnol. 2014, 5, 2230–2239, doi:10.3762/bjnano.5.232

• [FeIICrIII(CN)6]@CsI[NiIICrIII(CN)6] systems [26]. These core–multishell coordination nanoparticles were fabricated using a straightforward, surfactant-free manipulation with precise size control of the sample by controlling the addition rate and the concentration of the components. It is worth noting that

Influence of stabilising agents and pH on the size of SnO₂ nanoparticles

• Olga Rac,
• Patrycja Suchorska-Woźniak,
• Marta Fiedot and
• Helena Teterycz

Beilstein J. Nanotechnol. 2014, 5, 2192–2201, doi:10.3762/bjnano.5.228

• material increases the selectivity and sensitivity and shortens the response time of a sensor. However, the synthesis of SnO2 nanoparticles presents many difficulties. The following article presents a simple and inexpensive method for the synthesis of SnO2 nanoparticles. The influence of the surfactant and

• factor essential for good stabilisation of the nanoparticles was an appropriate acidity level of the solution. Under optimal conditions, nanoparticles having an average diameter of about 10 nm are reproducibly formed. Keywords: nanoparticles; polyethylenimine; polyvinylpyrrolidone; surfactant; tin

• composition, and a non-ionic surfactant. The influence of the individual reactants as well as the solution acidity on the dimensions of the resulting nanoparticles was analysed. The understanding of the interaction between these components of the solution is critical both for the synthesis of metal

Biopolymer colloids for controlling and templating inorganic synthesis

• Laura C. Preiss,
• Katharina Landfester and
• Rafael Muñoz-Espí

Beilstein J. Nanotechnol. 2014, 5, 2129–2138, doi:10.3762/bjnano.5.222

• ” geometries. In a very recent work, Taheri et al. [63] have presented the formation of potato starch capsules decorated with silver nanoparticles, which could have applications as drug carriers or antibacterial coatings. The capsules are prepared in an inverse (water-in-oil) miniemulsion and the surfactant

The impact of the confinement of reactants on the metal distribution in bimetallic nanoparticles synthesized in reverse micelles

• Concha Tojo,
• Elena González and
• Nuria Vila-Romeu

Beilstein J. Nanotechnol. 2014, 5, 1966–1979, doi:10.3762/bjnano.5.206

• surfactant which accumulates at the oil–water interface. The flexibility of the surfactant film surrounding micelles is a parameter associated with the interfacial curvature, which depends on the interactions on both sides of the interface. The flexibility is dictated by the microemulsion composition (mainly

• by the surfactant), and is directly related to the facility with which intermicellar channels can be established. The intermicellar exchange of material takes place through the intermicellar channel, thus the kinetics of the nanoparticle formation will strongly depend on the channel feature. Two

• aspects must be taken into account in order to establish how surfactant film flexibility is included in the simulation model. First, the material exchange between micelles will only be possible if the dimer remains intact for a sufficient amount of time. The longer that two colliding micelles stay

The surface properties of nanoparticles determine the agglomeration state and the size of the particles under physiological conditions

• Christoph Bantz,
• Olga Koshkina,
• Thomas Lang,
• Hans-Joachim Galla,
• C. James Kirkpatrick,
• Roland H. Stauber and
• Michael Maskos

Beilstein J. Nanotechnol. 2014, 5, 1774–1786, doi:10.3762/bjnano.5.188

• (organosiloxane) nanoparticles: Poly(organosiloxane) NPs are synthesized in an aqueous dispersion by co-condensation of mixtures of dialkyldialkoxysilanes and alkyltrialkoxysilanes in the presence of a surfactant. By sequential addition of mixtures with different ratios of bi- to tri-functional monomers

• nanotoxicology research: the investigation of the interaction of nanoparticles with the components of the alveolar surfactant film [71][72][73]. As the lung surfactant is the first barrier that inhaled nanoparticles encounter after passing the respiratory tract [74], interactions with this barrier are crucial in

• nanomaterial is mainly determined by three factors. The first one is the question of how the nanomaterial interacts with biological barriers. Here, interactions with the alveolar surfactant film are of special interest, because it is the first biological barrier after exposure via the lung. Therefore, the

Controlling the dispersion of supported polyoxometalate heterogeneous catalysts: impact of hybridization and the role of hydrophilicity–hydrophobicity balance and supramolecularity

• Gijo Raj,
• Colas Swalus,
• Eglantine Arendt,
• Pierre Eloy,
• Michel Devillers and
• Eric M. Gaigneaux

Beilstein J. Nanotechnol. 2014, 5, 1749–1759, doi:10.3762/bjnano.5.185

• hybrids are deposited. For instance, surfactant-encapsulated clusters of POM anions, formed through electrostatic interactions, were reported to form well-ordered straight nanorods on graphite [17], whereas hybrid materials formed through covalent functionalization of POM formed planar layer-by-layer

• surface, the alkyl chains of DODA are known to orient with a tilt angle of θ ≈ 30° with respect to the normal of the surface [30]. As expected, no epitaxial arrangement of DODA was observed. The conformation of the DODA surfactant, as shown here, can thus be tuned as a function of the surface properties

• driven through the electrostatic interaction of POM anions with the positively charged DODA surfactant. Firstly, we study the DODA–POM hybrids deposited on HOPG. Drop-casting of a small amount (about 9.5 µL) of a very dilute solution (0.025 g·L−1) allows for the formation of molecular layers that are of

Nanocrystalline ceria coatings on solid oxide fuel cell anodes: the role of organic surfactant pretreatments on coating microstructures and sulfur tolerance

• Chieh-Chun Wu,
• Ling Tang and
• Mark R. De Guire

Beilstein J. Nanotechnol. 2014, 5, 1712–1724, doi:10.3762/bjnano.5.181

• coatings from aqueous solution, were applied to anodes of solid oxide fuel cells. The cells were then operated in hydrogen/nitrogen fuel streams with H2S contents ranging from 0 to 500 ppm. Two surfactant treatments were studied: immersion in dodecanethiol, and a multi-step conversion of a siloxy-anchored

• [6][19][20][28]. In the present work the microstructural changes and the degree of sulfur tolerance were related to the presence or absence of the ceria coating, its morphology (which depended on the prior surfactant treatment), and the extent of sulfur exposure. Results First we illustrate general

• characteristics of the performance of the cells in sulfur-containing environments. Then SEM and EDXS analyses of the microstructures of the cells, before and after operation, with and without surfactant pretreatments are presented. The performance of the cells, grouped by type of anode treatment, is then

Non-covalent and reversible functionalization of carbon nanotubes

• Antonello Di Crescenzo,
• Valeria Ettorre and
• Antonella Fontana

Beilstein J. Nanotechnol. 2014, 5, 1675–1690, doi:10.3762/bjnano.5.178

• ionic surfactant such as sodium dodecyl sulfate (SDS). The chemical adsorption of SDS molecules on the surface of the nanotube induces electrostatic repulsion between polar heads that expose in the aqueous solution thus preventing CNTs aggregation and inducing the formation of stable aqueous black

• ultracentrifugation to equilibrium by exploiting a density gradient (see Figure 2) [62]. Different papers have faced the possible organizations of surfactant molecules on the surface of CNTs and still several conflicting evidences are reported in the literature. Richard et al. were among the first authors envisaging

• surfactant on the individual SWCNTs (see Figure 3, arrangement C). Analogously, we have evidenced [66][67] that gemini surfactants, characterized by two alkyl chains and two polar head groups separated by a spacer in a single molecule, are relatively effective dispersants also below their CMC or at very low

Silica nanoparticles are less toxic to human lung cells when deposited at the air–liquid interface compared to conventional submerged exposure

• Alicja Panas,
• Andreas Comouth,
• Harald Saathoff,
• Thomas Leisner,
• Marco Al-Rawi,
• Michael Simon,
• Gunnar Seemann,
• Olaf Dössel,
• Sonja Mülhopt,
• Hanns-Rudolf Paur,
• Susanne Fritsch-Decker,
• Carsten Weiss and
• Silvia Diabaté

Beilstein J. Nanotechnol. 2014, 5, 1590–1602, doi:10.3762/bjnano.5.171

• , the importance of shear forces to exacerbate NP-induced toxicity has been described previously [8][33]. Another explanation could also be the secretion of surfactant by A549 cells under ALI conditions [34] which may have a protective effect due to binding of surfactant proteins to the particles [35