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

• surrounding the particles fulfills specific requirements [1]. On the one hand the ligands have to stabilize the particles at high dilution in aqueous media, be non-toxic and provide a good shielding against biological conditions (e.g., ions, peptides, enzymes). On the other hand the control over the size and

• type of nanocontainers additional to the subsequently presented strategies. Functionalization properties For the biological use of encapsulated nanoparticles functionalizing of the capsules with relevant molecules (sugars, peptides), proteins or DNA is required. The most common coupling strategies are

Multifunctional layered magnetic composites

• Maria Siglreitmeier,
• Baohu Wu,
• Tina Kollmann,
• Martin Neubauer,
• Gergely Nagy,
• Dietmar Schwahn,
• Vitaliy Pipich,
• Damien Faivre,
• Dirk Zahn,
• Andreas Fery and
• Helmut Cölfen

Beilstein J. Nanotechnol. 2015, 6, 134–148, doi:10.3762/bjnano.6.13

• helix of (Gly–Pro–Hyp)n peptides) is contrasted to ion association to chitin. The latter model was chosen as three poly-(1,4)-D-glucose chains of about 40 Å length (which corresponds to nine monomers) stacked in three layers, which are connected by hydrogen bonds. As a starting point, the association of

Functionalization of α-synuclein fibrils

• Simona Povilonienė,
• Vida Časaitė,
• Virginijus Bukauskas,
• Arūnas Šetkus,
• Juozas Staniulis and
• Rolandas Meškys

Beilstein J. Nanotechnol. 2015, 6, 124–133, doi:10.3762/bjnano.6.12

• Physical Sciences and Technology, A. Gostauto 11, Vilnius LT-01108, Lithuania Institute of Botany of Nature Research Center, Zaliuju Ezeru 49, LT-08406 Vilnius, Lithuania 10.3762/bjnano.6.12 Abstract The propensity of peptides and proteins to form self-assembled structures has very promising applications

• self-assembled structures, amyloid proteins have become a very attractive material in the field of nanobiotechnology [1]. Many proteins or peptides can form amyloids under appropriate experimental conditions and recent studies suggest that amyloid formation is a generic property of the polypeptide

• tissue engineering [27][28], as well as use as a template for fibril metallization [29][30][31][32][33][34][35] or for the biomineralization of fibrils [36]. Nanostructures are usually designed by modifying proteins or peptides prior to fibril assembly [21][37][38][39][40][41]. Although post-assembly

Chemoselective silicification of synthetic peptides and polyamines

• Maryna Abacilar,
• Fabian Daus and
• Armin Geyer

Beilstein J. Nanotechnol. 2015, 6, 103–110, doi:10.3762/bjnano.6.10

• present experiments which quantify the additivity, and potential cooperativity of long chain polyamines (LCPAs) and cationic peptides in the silicification process. Keywords: biomineralisation; biosilicification; NMR spectroscopy; polyamines; silaffin; Introduction Modifications of the Stöber method [1

• components at the surface of the forming silica beads. Poulsen et al. investigated the mutual influence of peptides and LCPAs. Here we investigate the simplest scenario of chemoselective precipitation, which is the differentiation between two dissolved components, a cationic peptide and an oligoamine, that

• with the less capable Si precipitator in the presence of the better precipitator? Is there a measurable cooperativity between peptides and amines? Silica precipitation experiments are time consuming and error-prone because many actions are needed to separate the precipitate of amorphous silica, to dry

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

• peptides [112]. Consequently, this synthetic route allows precise control over nanoparticle composition, domain sizes, surface functionalization, and, also, surface charge. Biomedical applications When nanoparticles get in contact with body fluids, a variety of serum components binds to the surface of

• adsorption to silica particles of varying sizes and surface functionalization, it could be shown that small changes also are sufficient to drastically change to the affinity for peptides [116][117][118]. As a consequence, it is possible that slight structural differences of the silica shell of MnO and Fe3O4

Coating with luminal gut-constituents alters adherence of nanoparticles to intestinal epithelial cells

• Heike Sinnecker,
• Katrin Ramaker and
• Andreas Frey

Beilstein J. Nanotechnol. 2014, 5, 2308–2315, doi:10.3762/bjnano.5.239

• showed that the decrease in fluorescence at the cell surface was not associated with an increased fluorescence inside the cells, indicating that the protein coat had not led to an enhanced NP uptake by the cells. When analyzing the effect of NP treatment with meat extract, a mixture of peptides and amino

• acids representative for an alimentary peptide source, we noticed that this seemed to have no substantial effect on the adherence of NPs to the cells, only with the 20 nm NPs slightly higher fluorescence intensities were measured (Figure 2A). Individual peptides and amino acids of this extract do

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• working with a molecular concentration 104 times lower. This ultra-sensitive detection of non-labelled peptides achieved with SE-CARS is a brilliant example of single molecular detection and offers great perspectives for biomedical detection with very low molecular concentration threshold. Schlücker et al

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

• peptides. In situ formation of the inorganic material After having briefly discussed a few examples in which the inorganic material is formed ex situ and combined a posteriori with biopolymers, we will revise now in situ strategies, with biopolymers playing an active role during the formation of inorganic

•  2) [38]. In a more recent work, we have also shown that charged acidic peptides are able to stabilize vaterite, and we studied the effect of the acidity of the amino acid residues on this stabilization [39]. In a previous work, synthetic polymer colloidal particles functionalized with different

• to the surface of colloidal particles. In this sense, Krattiger et al. [44] reported the morphogenesis of CaCO3 and DL-alanine crystals in the presence of polystyrene beads functionalized with synthetic peptides with different amino acids and oligopeptides. B. Biopolymers as “supports” B1. Molecular

Electrostatic interplay: The interaction triangle of polyamines, silicic acid, and phosphate studied through turbidity measurements, silicomolybdic acid test, and ²⁹Si NMR spectroscopy

• Anne Jantschke,
• Katrin Spinde and
• Eike Brunner

Beilstein J. Nanotechnol. 2014, 5, 2026–2035, doi:10.3762/bjnano.5.211

• ]. They consist of linear oligo-propyleneimine chains attached to putrescine or spermine [5][6]. Biosilica-associated LCPAs occur either as free molecules [1][4] or covalently attached to the ε-amino groups of certain lysine-residues [7][8] in highly post-translationally modified peptides, so-called

Carbon-based smart nanomaterials in biomedicine and neuroengineering

• Antonina M. Monaco and
• Michele Giugliano

Beilstein J. Nanotechnol. 2014, 5, 1849–1863, doi:10.3762/bjnano.5.196

• consists of coating CNTs with surfactants, peptides, polymers, or nucleic acids, which preserve their aromatic structure, and (ii) the covalent approach [37][38][39], by means of applying several protocols, such as oxidation in strong acids, fluorination [40], and Bingel [41] and Billups [42] reactions

Real-time monitoring of calcium carbonate and cationic peptide deposition on carboxylate-SAM using a microfluidic SAW biosensor

• Anna Pohl and
• Ingrid M. Weiss

Beilstein J. Nanotechnol. 2014, 5, 1823–1835, doi:10.3762/bjnano.5.193

• the interaction of calcium carbonate with standard carboxylate self-assembled monolayer sensor chips. Different fluids, with and without biomolecular components, were investigated. The pH-dependent surface interactions of two bio-inspired cationic peptides, AS8 and ES9, which are similar to an

• organic biomolecules and calcium carbonate in the presence of carboxylate surfaces could be reproducibly quantified in real-time assays. Here, we report a case study with calcium carbonate, both in pure aqueous systems and in the presence of citric acid. We also investigated the two cationic peptides ES9

• detail with the particular aim to inspire similar investigations in biomineralization research in the future. A standard database of the function of organic molecules, peptides and proteins in mineralizing systems will be a major achievement of global significance for materials science, biomedical

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

• favorably exploited for CNTs precipitation/dispersion cycles. Ortiz-Acevedo et al. obtained a diameter-selective solubilization of SWCNTs by using cyclic peptides containing thiol groups [101]. The oxidation induces polymerization of the peptides which wrap around the nanotube achieving a size-selective

Donor–acceptor graphene-based hybrid materials facilitating photo-induced electron-transfer reactions

• Anastasios Stergiou,
• Georgia Pagona and
• Nikos Tagmatarchis

Beilstein J. Nanotechnol. 2014, 5, 1580–1589, doi:10.3762/bjnano.5.170

• , although graphene-based biomaterials are out of the scope of this mini-review, GO has been covalently functionalized with peptides, antibodies and other biomolecules for applications in diagnostics, novel therapeutic approaches and near infrared (NIR) photo-thermal therapies [53]. A representative work

Current state of laser synthesis of metal and alloy nanoparticles as ligand-free reference materials for nano-toxicological assays

• Christoph Rehbock,
• Jurij Jakobi,
• Lisa Gamrad,
• Selina van der Meer,
• Daniela Tiedemann,
• Ulrike Taylor,
• Wilfried Kues,
• Detlef Rath and
• Stephan Barcikowski

Beilstein J. Nanotechnol. 2014, 5, 1523–1541, doi:10.3762/bjnano.5.165

• oligonucleotides [52][86], peptides [87] and proteins [68], species native to biological systems and hence omnipresent in toxicity assays. However, in situ conjugation always entails the risk that nanoconjugates are destroyed by post irradiation [88][89][90], leading to pyrolysis products with unpredictable side

• demonstrated by Sajti et al. [92] where peptides were used as quenchers and particle diameter could be controlled in a range from 20–45 nm (Figure 4B, red curve). A complementary strategy involves variation of the residence time by flow rate in a range from 0.5–8 mL/min (corresponding to time delays of 4–54 s

In vitro interaction of colloidal nanoparticles with mammalian cells: What have we learned thus far?

• Moritz Nazarenus,
• Qian Zhang,
• Mahmoud G. Soliman,
• Pablo del Pino,
• Beatriz Pelaz,
• Susana Carregal-Romero,
• Joanna Rejman,
• Barbara Rothen-Rutishauser,
• Martin J. D. Clift,
• Reinhard Zellner,
• G. Ulrich Nienhaus,
• James B. Delehanty,
• Igor L. Medintz and
• Wolfgang J. Parak

Beilstein J. Nanotechnol. 2014, 5, 1477–1490, doi:10.3762/bjnano.5.161

• release from the intracellular vesicles to the cytosol [56][57][58] (and not the diffusion through (transient) membrane pores). Endosomal release is, for example, a scenario which has been unraveled in detail for NPs coated with certain cell penetrating peptides (CPPs) [59][60][61][62]. Thus, while NPs

A sonochemical approach to the direct surface functionalization of superparamagnetic iron oxide nanoparticles with (3-aminopropyl)triethoxysilane

• Bashiru Kayode Sodipo and
• Azlan Abdul Aziz

Beilstein J. Nanotechnol. 2014, 5, 1472–1476, doi:10.3762/bjnano.5.160

• peptides, antibodies, oligonucleotides or polymers [7][8][9][10][11][12][13]. As illustrated in Table 1, through a conventional method APTES can be grafted onto SPION by stirring, heating or combination of both heating and stirring. The combined heating and stirring process demonstrated to be the fastest

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

• , which were functionalised with RGD peptides. The adhesive gold nanoparticles had a diameter below 8 nm, which allowed the binding of one integrin molecule per RGD-functionalised nanoparticle [18]. If the distance between adjacent integrin-binding gold nanoparticles was less than 70 nm, cell adhesion was

Nanodiamond-DGEA peptide conjugates for enhanced delivery of doxorubicin to prostate cancer

• Amanee D Salaam,
• Patrick Hwang,
• Roberus McIntosh,
• Hadiyah N Green,
• Ho-Wook Jun and
• Derrick Dean

Beilstein J. Nanotechnol. 2014, 5, 937–945, doi:10.3762/bjnano.5.107

• NanoCarbon Research Institute (Osaka, Japan). DGEA peptide with a fluorescein isothiocyanate (FITC) tag attached via a lysine residue was purchased from Celtek Peptides (Nashville, TN). 1-Ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDAC) and N-hydroxysulfosuccinimide (sulfo-NHS) were purchased from Sigma

Controlling mechanical properties of bio-inspired hydrogels by modulating nano-scale, inter-polymeric junctions

• Seonki Hong,
• Hyukjin Lee and
• Haeshin Lee

Beilstein J. Nanotechnol. 2014, 5, 887–894, doi:10.3762/bjnano.5.101

• ) were acquired from Sigma-Aldrich (St. Louis, MO). 1-Hydroxybenzotriazole (HOBt) hydrate was purchased from Peptides International (Louisville, KY) and benzotriazole-1-yl-oxy-tris-(dimethylamino)-phosphonium hexafluorophosphate (BOP) was acquired from Novabiochem (Germany). Synthesis of catechol

Morphological characterization of fullerene–androsterone conjugates

• Alberto Ruiz,
• Margarita Suárez,
• Nazario Martin,
• Fernando Albericio and
• Hortensia Rodríguez

Beilstein J. Nanotechnol. 2014, 5, 374–379, doi:10.3762/bjnano.5.43

• suitably functionalized fullerene derivatives with physical and biological properties interesting for biomedicine and materials science [2]. The covalent linkage of C60 to moieties, such as porphyrins [3], anionic polymethine cyanine [4], and other bioactive molecules such as amino acids [5], peptides [6

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

• chemical bottom-up syntheses under similar conditions [21]. In these biomimetic syntheses, peptides are used which influence the inorganic crystal growth by different mechanisms, such as catalysis or surface adsorption. It was previously shown that c25-mms6, a short synthetic version of the protein MMS6

Controlled synthesis and tunable properties of ultrathin silica nanotubes through spontaneous polycondensation on polyamine fibrils

• Jian-Jun Yuan,
• Pei-Xin Zhu,
• Daisuke Noda and
• Ren-Hua Jin

Beilstein J. Nanotechnol. 2013, 4, 793–804, doi:10.3762/bjnano.4.90

• conditions. However, the formation of silica nanotubes needs relatively long reaction times (i.e., several days), and the use of the peptides as templates is costly. In order to achieve a large-scale commercial application of silica nanotubes, a highly efficient low-cost strategy based on simple synthetic

Molecular dynamics simulations of mechanical failure in polymorphic arrangements of amyloid fibrils containing structural defects

• Hlengisizwe Ndlovu,
• Alison E. Ashcroft,
• Sheena E. Radford and
• Sarah A. Harris

Beilstein J. Nanotechnol. 2013, 4, 429–440, doi:10.3762/bjnano.4.50

• properties are modulated by incorporating chemical capping groups to neutralise the N- and C-termini of the peptides. In a previous simulation study to determine the sequence dependence of the resistance of amyloid fibrils to mechanical stress by using SMD [23], we highlighted the importance of structural

• . The nomenclature adopted throughout is Class1-P (parallel β-sheets), Class2-P (parallel β-sheets) and Class6-AP (antiparallel β-sheets). Mechanical responses of 8 × 2 fibril models We first model the fibril polymorphs as two interfaced β-sheets, each of which comprises eight peptides (8 × 2 models

• understood by examining the intersheet interfaces that are affected during the SMD simulation. Both “slide” and “peel” modes disrupt the electrostatic interactions between the charged termini and force the hydrophobic core to be exposed to solvent molecules. For the three polymorphs containing eight peptides

Nanoscopic surfactant behavior of the porin MspA in aqueous media

• Ayomi S. Perera,
• Hongwang Wang,
• Tej B. Shrestha,
• Deryl L. Troyer and
• Stefan H. Bossmann

Beilstein J. Nanotechnol. 2013, 4, 278–284, doi:10.3762/bjnano.4.30

• strength and especially the temperature on the size of the MspA-vesicles and their zeta potentials, ζ. The influence of temperature on the 3D-aggregation behavior of peptides is rarely discussed, because the temperature is well defined in many living organisms and only a few proteins do not denature at

Controlled deposition and combing of DNA across lithographically defined patterns on silicon

• Zeinab Esmail Nazari and
• Leonid Gurevich

Beilstein J. Nanotechnol. 2013, 4, 72–76, doi:10.3762/bjnano.4.8

• stretching of various DNA–peptide conjugates. These nanomaterials have been recently prepared by our team and are composed of a dsDNA core and peripheral coating layer of self-assembled cationic peptides [21][22]. Results and Discussion As was mentioned above, DNA molecules acquire a relatively compact

• –peptide conjugates, while the original recipe was proven to be ineffective for combing these materials [11]. Figure 3 represents the topography of combed dsDNA conjugated with various peptides. Combing across nanoelectrodes was also possible for DNA–peptide conjugates (Figure 3e). The gas-phase deposition

• , Sigma Aldrich) was used as a buffer in all the procedures described here. The DNA solution was buffer exchanged to ammonium acetate before use, to guarantee that only “volatile” ions are present on the substrate. The following peptides were used to form DNA–peptide conjugates: indolicidin, abbreviated