High photocatalytic activity of V-doped SrTiO₃ porous nanofibers produced from a combined electrospinning and thermal diffusion process

• Panpan Jing,
• Wei Lan,
• Qing Su and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 1281–1286, doi:10.3762/bjnano.6.132

• typical preparation procedure as follows. Firstly, pure SrTiO3 nanofibers were prepared via electrospinning followed by heat treatment. 0.25 g of poly(vinylpyrrolidone) (PVP, Mw = 1,300,000) and 0.34 g of Ti(C4H9O)4 were completely dissolved in a mixed solvent comprised of 0.6 g N,N-dimethylformamide (DMF

Synthesis, characterization and in vitro effects of 7 nm alloyed silver–gold nanoparticles

• Simon Ristig,
• Svitlana Chernousova,
• Wolfgang Meyer-Zaika and
• Matthias Epple

Beilstein J. Nanotechnol. 2015, 6, 1212–1220, doi:10.3762/bjnano.6.124

• (vinylpyrrolidone) (PVP). This ligand efficiently replaces the citrate, as previously demonstrated for gold nanoparticles [32]. A purification of the nanoparticles to remove the synthesis byproducts was achieved by multiple ultracentrifugation steps and did not affect the stability of the dispersions. The alloyed

• reducing agents (citrate and tannic acid) were used to generate nanoparticles with mean diameters of 6 to 7 nm. The primary ligands, citrate and tannic acid, were replaced by PVP after the synthesis. For comparison, pure gold and silver nanoparticles were synthesized with the same reaction parameters. The

•  1 show a representative series of Ag/Au 10:90, 30:70, and 90:10 nanoparticles with PVP stabilization. TEM alone cannot be used to determine the dispersion of nanoparticles in solution [33][34][35]. DCS analysis showed that the purified samples did not contain any agglomerates and maintained a high

High sensitivity and high resolution element 3D analysis by a combined SIMS–SPM instrument

• Yves Fleming and
• Tom Wirtz

Beilstein J. Nanotechnol. 2015, 6, 1091–1099, doi:10.3762/bjnano.6.110

• spectrometry (SIMS) data was combined with topographical data from the scanning probe microscopy (SPM) module for five test structures in order to obtain accurate chemical 3D maps: a polystyrene/polyvinylpyrrolidone (PS/PVP) polymer blend, a nickel-based super-alloy, a titanium carbonitride-based cermet, a

• a non-flat surface) and inhomogeneities of the secondary ion extraction efficiencies due to local field distortions (caused by topography with high aspect ratios). In this respect, this paper presents the measured relative sputter rates between PVP and PS as well as in between the different phases

• is widely used in the SIMS field. The 3D SIMS-AFM surface reconstructions are visualised using the SPIP™ software by Image Metrology [15], the ParaView software tool [16] as well as the MayaVI 2 software tool [17]. Results and Discussion PS/PVP polymer blend An annealed polystyrene (PS

From lithium to sodium: cell chemistry of room temperature sodium–air and sodium–sulfur batteries

• Philipp Adelhelm,
• Pascal Hartmann,
• Conrad L. Bender,
• Martin Busche,
• Christine Eufinger and
• Juergen Janek

Beilstein J. Nanotechnol. 2015, 6, 1016–1055, doi:10.3762/bjnano.6.105

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

• (diameter 40 ± 10 nm) NPs, specifically addressing the effect of a (poly)vinylpyrrolidone (PVP) coating around the metallic surface on the protein adsorption/desorption equilibrium. For citrate-stabilized Au and Ag NPs, they found affinities in a low nanomolar concentration regime (KD(Au) = 33 ± 3.2 nM, KD

• (Ag) = 20 ± 1.1 nM) [47], confirming an extremely high affinity of proteins towards these surfaces. When the PVP coatings were applied around the NPs, the affinities were found to be significantly lower (KD(Au–PVP) = 0.5 ± 0.05 µM, KD(Ag–PVP) = 0.2 ± 0.05 µM) [47]. These findings underline the

Morphology control of zinc oxide films via polysaccharide-mediated, low temperature, chemical bath deposition

• Florian Waltz,
• Hans-Christoph Schwarz,
• Andreas M. Schneider,
• Stefanie Eiden and
• Peter Behrens

Beilstein J. Nanotechnol. 2015, 6, 799–808, doi:10.3762/bjnano.6.83

• -based chemical deposition processes are particularly suited for the addition of molecules that may affect the morphology of ZnO crystals and their aggregates as well as of ZnO films. Molecules such as citrate [31][32], histidine [33], 1-butan-2-ylpyrrolidin-2-one (PVP) [34][35], 2-hydroxybutanedioate

Microwave assisted synthesis and characterisation of a zinc oxide/tobacco mosaic virus hybrid material. An active hybrid semiconductor in a field-effect transistor device

• Shawn Sanctis,
• Rudolf C. Hoffmann,
• Sabine Eiben and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2015, 6, 785–791, doi:10.3762/bjnano.6.81

• the zinc oximato complex and polyvinylpyrrolidone (PVP) (mol. wt ≈ 10k) in methanol and drop wise addition of a solution of tetraethylammonium hydroxide (TEAOH) in methanol, so that the final concentrations were [Zn2+] = 10 mM, [PVP] = 10 mM, and [TEAOH] = 12.5 mM. The microwave reactions were

• using a methanolic solution of zinc complex as a zinc source and polyvinylpyrrolidone (PVP) as a growth inhibiting and stabilizing agent for the zinc oxide nanoparticles. PVP has been reported to have a higher efficiency in suppressing the growth of zinc oxide during its formation, in comparison to

• (101) planes are characteristic of the zincite structure (Figure 2b). A greater intensity in the direction of the c-axis (i.e., perpendicular to the (002) plane) was observed. ZnO nanoparticles undergo an oriented attachment during thin film formation in the presence of PVP which hints at texturing of

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

Tunable white light emission by variation of composition and defects of electrospun Al₂O₃–SiO₂ nanofibers

• Jinyuan Zhou,
• Gengzhi Sun,
• Hao Zhao,
• Xiaojun Pan,
• Zhenxing Zhang,
• Yujun Fu,
• Yanzhe Mao and
• Erqing Xie

Beilstein J. Nanotechnol. 2015, 6, 313–320, doi:10.3762/bjnano.6.29

• ][34], this IR peak at 790 cm−1 likely corresponds to the vibration of Si–C–O bonds formed due to the residual carbon elements from PVP or ethanol. In the range of 950–1330 cm−1, the main peak intensity increases with increasing Si content, and this peak at ≈1120 cm−1 should be assigned to the

• emission from the intersystem radiative crossing. This research may provide a new strategy for the preparation of environmentally friendly, white light luminescence materials. Experimental Preparation of Al2O3–SiO2 composite nanofibers Poly(vinylpyrrolidone) (PVP, Mw ≈1,300,000) was purchased from Sigma

• and used as received without any further purification. Al2O3–SiO2 hetero-nanofibers were prepared by electrospinning, the details of which can be reviewed from previously published work [41][42][43][44]. Briefly, sol–gel aqueous solutions were prepared by dissolving TEOS, Al(NO3)3·9H2O, and PVP powder

Proinflammatory and cytotoxic response to nanoparticles in precision-cut lung slices

• Stephanie Hirn,
• Nadine Haberl,
• Kateryna Loza,
• Matthias Epple,
• Wolfgang G. Kreyling,
• Barbara Rothen-Rutishauser,
• Markus Rehberg and
• Fritz Krombach

Beilstein J. Nanotechnol. 2014, 5, 2440–2449, doi:10.3762/bjnano.5.253

• polyvinylpyrrolidone (PVP)-coated Ag-NPs under submerged culture conditions in vitro. ZnO-NPs (NM110) served as ‘soluble’ and quartz particles (Min-U-Sil) as ‘non-soluble’ control particles. After 4 and 24 h, the cell viability and the release of proinflammatory cytokines was measured. In addition, multiphoton

• proinflammatory response of PCLS to Ag-NPs through LDH assay, WST-1 assay, and CXCL-1 and TNF-α ELISAs. The PVP-coated Ag-NPs used in this study have been already demonstrated to induce a cytotoxic and/or proinflammatory response in vivo and in vitro [25][26]. Moreover, ZnO-NPs served as a soluble control and

• quartz particles as a non-soluble control, since both particle types have been shown to elicit cytotoxic as well as inflammatory responses in both in vitro and in vivo assays [27][28]. Interestingly enough, the PVP-coated Ag-NPs used in this study only induced a slight cytotoxic, but not an inflammatory

Synthesis and characterization of fluorescence-labelled silica core-shell and noble metal-decorated ceria nanoparticles

• Rudolf Herrmann,
• Markus Rennhak and
• Armin Reller

Beilstein J. Nanotechnol. 2014, 5, 2413–2423, doi:10.3762/bjnano.5.251

• stabilize the NP with surfactants like IGEPAL CO-520 but with no appreciable success. The only efficient approach up to now to controlled agglomeration of ceria NP is their synthesis from cerium(III) nitrate in ethanol/water mixtures in the presence of polyvinylpyrrolidone (PVP), at temperatures exceeding

• 120 °C [48]. Under these conditions, nitrate acts as oxidizing agent, and the reaction can be done in closed vessels. The overall reaction is 3Ce3+ + NO3− + 4H2O → 3CeO2 + NO + 8H+. The authors suggest that PVP interacts with the crystal seeds and prevents an increase in size over the limit of 8–10 nm

• . These particles then agglomerate by merging their PVP coverings until a maximum size under the reacion conditions is reached. Upon prolonged reaction the particles may undergo ruptures and decrease their size again. This mechanism has been suggested ad hoc from the observation of size and shape

Interaction of dermatologically relevant nanoparticles with skin cells and skin

• Annika Vogt,
• Fiorenza Rancan,
• Sebastian Ahlberg,
• Berouz Nazemi,
• Chun Sik Choe,
• Maxim E. Darvin,
• Sabrina Hadam,
• Ulrike Blume-Peytavi,
• Kateryna Loza,
• Jörg Diendorf,
• Matthias Epple,
• Christina Graf,
• Eckart Rühl,
• Martina C. Meinke and
• Jürgen Lademann

Beilstein J. Nanotechnol. 2014, 5, 2363–2373, doi:10.3762/bjnano.5.245

• microscope (Zeiss EM906). Detection of silver particle-mediated production of reactive oxygen specimen by EPR spectroscopy: The PVP-coated silver nanoparticles were prepared as described in Loza et al. [46]. They had a negative zeta-potential of −20 mV and a diameter of the metallic core of 70 nm. They were

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

• , polyethylenimine (PEI) or polyvinylpyrrolidone (PVP), and t-octylphenoxypolyethoxyethanol (Triton X-100) as a surfactant with a hydrophilic–lipophilic balance (HBL) of 13.5. Anhydrous tin(IV) chloride is a strong Lewis acid and easily forms complexes [21]. In contrast, PEI is a synthetic cationic polymer which may

• ) and polyvinylpyrrolidone (PVP), with three different average molar masses were used in the study. As demonstrated by the results of this study, in case of PVP, large tin dioxide particles approximately 1–2 µm in diameter were obtained (Table 2). The analysis of the results clearly showed that

• processes can be effectively controlled with the acidity of the solution, because PEI (which has undergone deprotonation) does not stabilise the nanoparticles. In the presence of PVP (the second of the stabilisers used, Table 2 and Table 5), the process happens differently. PVP is a linear, polyelectrolyte

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

• healing [8]. In our previous studies on the biological effects of Ag-NP (PVP-coated, 80 nm) on human mesenchymal stem cells (hMSCs), we have shown that cell activation could occur at elevated but non-toxic silver concentrations [9][10]. In addition, we have shown that hMSCs are able to ingest Ag-NP

• predict the possible health risks. Experimental Synthesis of silver nanoparticles Polyvinylpyrrolidone (PVP)-coated silver nanoparticles were synthesized by reduction with glucose in the presence of PVP as described previously [19][21]. The final silver concentration in all dispersions was determined by

• . 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

PVP-coated, negatively charged silver nanoparticles: A multi-center study of their physicochemical characteristics, cell culture and in vivo experiments

• Sebastian Ahlberg,
• Alexandra Antonopulos,
• Jörg Diendorf,
• Ralf Dringen,
• Matthias Epple,
• Rebekka Flöck,
• Wolfgang Goedecke,
• Christina Graf,
• Nadine Haberl,
• Jens Helmlinger,
• Fabian Herzog,
• Frederike Heuer,
• Stephanie Hirn,
• Christian Johannes,
• Stefanie Kittler,
• Manfred Köller,
• Katrin Korn,
• Wolfgang G. Kreyling,
• Fritz Krombach,
• Jürgen Lademann,
• Kateryna Loza,
• Eva M. Luther,
• Marcelina Malissek,
• Martina C. Meinke,
• Daniel Nordmeyer,
• Anne Pailliart,
• Jörg Raabe,
• Fiorenza Rancan,
• Barbara Rothen-Rutishauser,
• Eckart Rühl,
• Carsten Schleh,
• Andreas Seibel,
• Christina Sengstock,
• Lennart Treuel,
• Annika Vogt,
• Katrin Weber and
• Reinhard Zellner

Beilstein J. Nanotechnol. 2014, 5, 1944–1965, doi:10.3762/bjnano.5.205

• main text. 10.3762/bjnano.5.205 Abstract PVP-capped silver nanoparticles with a diameter of the metallic core of 70 nm, a hydrodynamic diameter of 120 nm and a zeta potential of −20 mV were prepared and investigated with regard to their biological activity. This review summarizes the physicochemical

• silver nanoparticles were chemically characterized, purified from synthesis by-products and the silver content in the dispersions was measured for each batch. Unless otherwise noted, in all cases in which silver nanoparticles are referred to in the following sections, they are PVP-coated with a negative

• trifluoroacetate) is reduced by the solvent ethylene glycol at temperatures of 140–180 °C in the presence of poly(N-vinylpyrrolidone); PVP) [22]. PVP serves as capping agent and stabilizes the formed nanoparticles against agglomeration, but also plays a role in the formation of specific shapes such as cubes or

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

• biokinetics of grafted AuNP conjugates. However, these results also suggest that more research is required to better understand the mechanisms of how these proteins and others mediate the passage across organ membranes. Precision-cut lung slices after intratracheal instillation of PVP-coated silver NP Several

• proteomics and cellular analyses of lung tissue exposed to AgNP and Ag ions as well as more realistic bacterial post-exposures. We used monodisperse, spherical, PVP-coated AgNP with a size of 70 nm which had been carefully characterized [26][27]. The AgNP were dispersed in degassed distilled water and the

Synthesis, characterization, and growth simulations of Cu–Pt bimetallic nanoclusters

• Subarna Khanal,
• Ana Spitale,
• Nabraj Bhattarai,
• Daniel Bahena,
• J. Jesus Velazquez-Salazar,
• Sergio Mejía-Rosales,
• Marcelo M. Mariscal and
• Miguel José-Yacaman

Beilstein J. Nanotechnol. 2014, 5, 1371–1379, doi:10.3762/bjnano.5.150

• -like structures for the Cu–Pt system, and core–shell structures for Au–Pt and Ag–Pt. Yu et al. [35] investigated the formation of and dealloying of CuPt bimetallic nanoparticles in presence of hexadecylamine or PVP as capping agents, obtaining different morphologies of nanoparticles depending on their

Mimicking exposures to acute and lifetime concentrations of inhaled silver nanoparticles by two different in vitro approaches

• Fabian Herzog,
• Kateryna Loza,
• Sandor Balog,
• Martin J. D. Clift,
• Matthias Epple,
• Peter Gehr,
• Alke Petri-Fink and
• Barbara Rothen-Rutishauser

Beilstein J. Nanotechnol. 2014, 5, 1357–1370, doi:10.3762/bjnano.5.149

• (diameter 100 nm; coated with polyvinylpyrrolidone: PVP). Ag NPs were found to be highly aggregated within ALI exposed cells with no impairment of cell morphology. Furthermore, a significant increase in release of cytotoxic (LDH), oxidative stress (SOD-1, HMOX-1) or pro-inflammatory markers (TNF-α, IL-8

• study [44] we used polyvinylpyrrolidone (PVP)-coated Ag NPs with a larger size. Those particles are well characterized and have been previously used in other studies [45][46]. In addition, the results between air–liquid interface (ALI) and submerged exposures to different concentrations were performed

• in order to reveal a greater insight into the effect of Ag NP toxicity. Results Particle characterisation PVP-coated Ag NPs were characterised by scanning electron microscopy (SEM) and dynamic light scattering (DLS). Figure 1A shows a representative SEM image of particles deposited on a silicon wafer

Preparation of poly(N-vinylpyrrolidone)-stabilized ZnO colloid nanoparticles

• Tatyana Gutul,
• Emil Rusu,
• Nadejda Condur,
• Veaceslav Ursaki,
• Evgenii Goncearenco and
• Paulina Vlazan

Beilstein J. Nanotechnol. 2014, 5, 402–406, doi:10.3762/bjnano.5.47

• ., Chisinau MD-2009, Moldova National Institute of Electrochemistry and Condensed Matter, 144 Dr. A. Paunescu Podeanu str., Timisoara 300569, Romania 10.3762/bjnano.5.47 Abstract We propose a method for the synthesis of a colloidal ZnO solution with poly(N-vinylpyrrolidone) (PVP) as stabilizer. Stable

• colloidal solutions with good luminescence properties are obtained by using PVP as stabilizer in the synthesis of ZnO nanoparticles by a sol–gel method assisted by ultrasound. Nanoparticles with sizes of 30–40 nm in a PVP matrix are produced as a solid product. The colloidal ZnO/PVP/methanol solution, apart

• from the most intense PL band at 356 nm coming from the PVP, exhibits a strong PL band at 376 nm (3.30 eV) which corresponds to the emission of the free exciton recombination in ZnO nanoparticles. Keywords: colloidal solutions; nanocomposite; poly(N-vinylpyrrolidone); sol–gel; zinc oxide

Cytotoxic and proinflammatory effects of PVP-coated silver nanoparticles after intratracheal instillation in rats

• Nadine Haberl,
• Stephanie Hirn,
• Alexander Wenk,
• Jörg Diendorf,
• Matthias Epple,
• Blair D. Johnston,
• Fritz Krombach,
• Wolfgang G. Kreyling and
• Carsten Schleh

Beilstein J. Nanotechnol. 2013, 4, 933–940, doi:10.3762/bjnano.4.105

• rats. Monodisperse, PVP-coated AgNP (70 nm) showing little agglomeration in aqueous suspension were instilled intratracheally. After 24 hours, the lungs were lavaged, and lactate dehydrogenase (LDH), total protein, and cytokine levels as well as total and differential cell counts were measured in the

• bronchoalveolar lavage fluid (BALF). Instillation of 50 µg PVP-AgNP did not result in elevated LDH, total protein, or cytokine levels in BALF compared to the control, whereas instillation of 250 µg PVP-AgNP caused a significant increase in LDH (1.9-fold) and total protein (1.3-fold) levels as well as in

• neutrophil numbers (60-fold) of BALF. Furthermore, while there was no change in BALF cytokine levels after the instillation of 50 µg PVP-AgNP, instillation of 250 µg PVP-AgNP resulted in significantly increased levels of seven out of eleven measured cytokines. These finding suggest that exposure to inhaled

Energy transfer in complexes of water-soluble quantum dots and chlorin e6 molecules in different environments

• Irina V. Martynenko,
• Anna O. Orlova,
• Vladimir G. Maslov,
• Alexander V. Baranov,
• Anatoly V. Fedorov and
• Mikhail Artemyev

Beilstein J. Nanotechnol. 2013, 4, 895–902, doi:10.3762/bjnano.4.101

• should be taken into account. On the other hand, QY of Ce6 PL in the complexes is about 3 times lower than that in Ce6 bound with PVP [17] and 2 times lower than that for Ce6 in aqueous solutions. Appearance of new channels of Ce6 energy dissipation due to perturbation of the molecule under complexing or

Electrospinning preparation and electrical and biological properties of ferrocene/poly(vinylpyrrolidone) composite nanofibers

• Ji-Hong Chai and
• Qing-Sheng Wu

Beilstein J. Nanotechnol. 2013, 4, 189–197, doi:10.3762/bjnano.4.19

• 200433, PR China 10.3762/bjnano.4.19 Abstract Nanofibers containing ferrocene (Fc) have been prepared for the first time by electrospinning. In this paper, Fc was dispersed uniformly throughout the poly(vinypyrrolidone) (PVP) matrix for the purpose of combining the properties of PVP and Fc. The effects

• PVP nanofibers. X-ray diffraction (XRD) results showed that the crystalline structure of Fc in the fibers was amorphous after the electrospinning process. A biological evaluation of the antimicrobial activity of Fc/PVP nanofibers was carried out by using Gram-negative Escherichia coli (E. coli) as

• inside PVP nanofibers retian their electrochemical activity. The properties and facile preparation method make the Fc/PVP nanofibers promising for antibacterial and sensing applications. Keywords: composites; electrochemistry; electrospinning; membranes; porous materials; Introduction Electrospinning

Characterization and properties of micro- and nanowires of controlled size, composition, and geometry fabricated by electrodeposition and ion-track technology

• Maria Eugenia Toimil-Molares

Beilstein J. Nanotechnol. 2012, 3, 860–883, doi:10.3762/bjnano.3.97

• containing Zn(NO3), Co(NO3), nitric acid, and polyvinylpyrrolidone (PVP) as an additive, 300 nm diameter Zn1−xCoxO nanowires with x ranging from 0.01 to 0.05 were grown [94]. The synthesis and properties of semiconducting CdTe and CdS nanowires are being investigated for their potential in photodetector and

Room temperature synthesis of indium tin oxide nanotubes with high precision wall thickness by electroless deposition

• Mario Boehme,
• Emanuel Ionescu,
• Ganhua Fu and
• Wolfgang Ensinger

Beilstein J. Nanotechnol. 2011, 2, 119–126, doi:10.3762/bjnano.2.14

• ) membrane filters, exposed in a very controlled way to charged particles in a nuclear reactor, were obtained from Whatman/GE™ and comparable companies. Because the surface of the commercial membrane filters was treated with polyvinylpyrrolidone (PVP), an additional etching process was used to remove the PVP

Preparation and characterization of supported magnetic nanoparticles prepared by reverse micelles

• Ulf Wiedwald,
• Luyang Han,
• Johannes Biskupek,
• Ute Kaiser and
• Paul Ziemann

Beilstein J. Nanotechnol. 2010, 1, 24–47, doi:10.3762/bjnano.1.5

• the PS- and hydrophilicity of PVP-block, the co-polymers form reverse spherical micelles in apolar solvents such as the solvent used here, i.e., toluene. Empirically, however, in order to obtain stable spherical micelles, the block length of PS, x, should be significantly larger than the PVP length y