Single-molecule mechanics of protein-labelled DNA handles

• Vivek S. Jadhav,
• Dorothea Brüggemann,
• Florian Wruck and
• Martin Hegner

Beilstein J. Nanotechnol. 2016, 7, 138–148, doi:10.3762/bjnano.7.16

• and coupling to polystyrene beads PCR amplification of plasmid pTYB1 (7477 bp, New England Biolabs, Ireland (NEB)) with 5’-biotin (5’-AAT TCT TGA AGA CGA AAG GGC GGC-3’ for 4056 bp DNA and 5’-GGA TAC GAC GAT ACC GAA GAC AGC-3’ for 3034 bp DNA) and 5’-thiol or 5’-DIG end-modified primers (both have the

• OT setup. For DNA with DIG at the 5’ end and thiol at the 3’ end a PCR using the 7477 bp long plasmid pTYB1 was carried out with 5’-DIG end-modified and 5’-thiol end-modified primers. Subsequently, the thiol-end was covalently coupled to amino-beads with 2.1 µm diameter (Spherotech, Lake Forest, IL

• , USA) using a sulfo-SMCC cross linker (Fisher Scientific, Dublin, Ireland). DIG-DNA-Thiol was activated for 1 h at room temperature with a ratio of approx. 1000 SMCC molecules per DNA as previously described [8]. Excess of SMCC was removed using a ChargeSwitch® cleaning kit, and the activated DNA was

Surface-site reactivity in small-molecule adsorption: A theoretical study of thiol binding on multi-coordinated gold clusters

• Elvis C. M. Ting,
• Tatiana Popa and
• Irina Paci

Beilstein J. Nanotechnol. 2016, 7, 53–61, doi:10.3762/bjnano.7.6

• ; sulfur–gold interactions; thiol adsorption; Introduction The interactions between organic molecules and metallic surfaces have been the subject of significant interest in recent years, because of their fundamental relevance in a broad array of nanoscience applications. One area of interfacial research

• , given its broad relevance in spectroscopy, sensing, nanotechnology and biophysics. Many reviews have been written in the last two decades on the topic of thiol adsorption on gold flat surfaces and clusters [50][51][52][53][54][55][56][57][58][59][60][61][62], and on that of aminoacid–gold binding [3][10

• adsorption case, as considering the complex in the molecular (gold + adsorbate) basis set is appropriate in the context of chemical bonding of the two. Results and Discussion Dissociative binding of methyl thiol on the Au20 cluster Despite the small size of the molecular backbones considered in this study

Effects of electronic coupling and electrostatic potential on charge transport in carbon-based molecular electronic junctions

• Richard L. McCreery

Beilstein J. Nanotechnol. 2016, 7, 32–46, doi:10.3762/bjnano.7.4

• of molecules oriented between two conductors, with charge transport through the molecular layer. The vast majority of existing junction structures are based on metal/molecule bonding such as the Au/thiol self-assembled monolayers [13][14][15][16][17][18][19][20][21], Langmuir–Blodgett films on metals

Chemiresistive/SERS dual sensor based on densely packed gold nanoparticles

• Sanda Boca,
• Cosmin Leordean,
• Simion Astilean and
• Cosmin Farcau

Beilstein J. Nanotechnol. 2015, 6, 2498–2503, doi:10.3762/bjnano.6.259

• transfer, which is in turn observed as a resistance decrease. Moreover, in our system MBA is a thiol-terminated molecule while folic acid is not, and therefore one can expect that the MBA molecules can replace folic acid ligands from the surface of the gold particles. MBA is smaller than folic acid, and

Nanostructured surfaces by supramolecular self-assembly of linear oligosilsesquioxanes with biocompatible side groups

• Maria Nowacka,
• Anna Kowalewska and
• Tomasz Makowski

Beilstein J. Nanotechnol. 2015, 6, 2377–2387, doi:10.3762/bjnano.6.244

• cyclic tetravinylsiloxanetetraols [50]. The thiol-ene additions were photoinitiated by 2,2-dimethoxy-2-phenylacetophenone (DMPA) (full experimental data can be found in Supporting Information File 1). Thin layers of LPSQ-COOH/X were deposited onto freshly cleaved mica substrates by dip coating from their

• compounds patches of base layers can be observed that are more smooth (Rq = 0.077 and 0.047 nm). They do not exhibit clear phase contrast and it cannot be asserted whether they are areas of well-packed molecules or bare mica (Rq = 0.032 nm for bare mica). The surface of mica covered with TG bearing thiol

• . A similar trend can be observed for samples adsorbed on supports pretreated with mica-TG or mica-NAC (Figure 8 and Figure 9). Thiol groups are present on both surfaces. Thiols are more nucleophilic than hydroxyls and thus their ability for the formation of hydrogen bonds is different. P1 produces

Self-organization of gold nanoparticles on silanated surfaces

• Htet H. Kyaw,
• Salim H. Al-Harthi,
• Azzouz Sellai and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2015, 6, 2345–2353, doi:10.3762/bjnano.6.242

• Molecular self-assembly or self-organization is a technique which is widely used for the spontaneous arrangement of nanomaterials. Coupling agents such as thiol-terminated, amine-terminated, alkyl-terminated and phenyl-terminated silanes on metal nanoparticles (so called adsorbates) attach on various

Surfactant-controlled composition and crystal structure of manganese(II) sulfide nanocrystals prepared by solvothermal synthesis

• Elena Capetti,
• Anna M. Ferretti,
• Vladimiro Dal Santo and
• Alessandro Ponti

Beilstein J. Nanotechnol. 2015, 6, 2319–2329, doi:10.3762/bjnano.6.238

• precursor. When we used a single surfactant (carboxylic acid, alcohol, thiol, amine), α-MnS nanocrystals were obtained. The peculiar role of the amine seems to be related to its basicity. The nanocrystals were characterized by TEM and electron diffraction; ATR-FTIR spectroscopy provided information about

• , alcohol, and thiol surfactants. This set allowed us to understand how basicity, nucleophilicity and ability to undergo condensation reaction with stearic acid affect the structure directing ability of the surfactant. The crystal structure of the resulting NCs was determined by analyzing the electron

Orthogonal chemical functionalization of patterned gold on silica surfaces

• Francisco Palazon,
• Didier Léonard,
• Thierry Le Mogne,
• Francesca Zuttion,
• Céline Chevalier,
• Magali Phaner-Goutorbe,
• Éliane Souteyrand,
• Yann Chevolot and
• Jean-Pierre Cloarec

Beilstein J. Nanotechnol. 2015, 6, 2272–2277, doi:10.3762/bjnano.6.233

• martyrs, 38054 Grenoble, France 10.3762/bjnano.6.233 Abstract Single-step orthogonal chemical functionalization procedures have been developed with patterned gold on silica surfaces. Different combinations of a silane and a thiol were simultaneously deposited on a gold/silica heterogeneous substrate. The

• orthogonality of the functionalization (i.e., selective grafting of the thiol on the gold areas and the silane on the silica) was demonstrated by X-ray photoelectron spectroscopy (XPS) as well as time-of-flight secondary ion mass spectrometry (ToF–SIMS) mapping. The orthogonal functionalization was used to

• Discussion Micropatterned gold on a silica substrate (with features of ≈100 µm) functionalized with either (1) 1H,1H,2H,2H-perfluorodecanethiol and 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane (F-thiol + PEG/Si) or (2) trichloro(1H,1H,2H,2H-perfluorooctyl)silane and 11-mercapto-1-undecanoic acid (F

Optimized design of a nanostructured SPCE-based multipurpose biosensing platform formed by ferrocene-tethered electrochemically-deposited cauliflower-shaped gold nanoparticles

• Wicem Argoubi,
• Maroua Saadaoui,
• Sami Ben Aoun and
• Noureddine Raouafi

Beilstein J. Nanotechnol. 2015, 6, 1840–1852, doi:10.3762/bjnano.6.187

• that were tethered with a β-cyclodextrin/ferrocene inclusion complex as a transducing system. Connection between gold and the ferrocene host was achieved thanks to a thiol terminal group [13]. The ferrocene complex acted as an electron shuttle allowing for glucose oxidation at low potentials. Li et al

Imaging of carbon nanomembranes with helium ion microscopy

• André Beyer,
• Henning Vieker,
• Robin Klett,
• Hanno Meyer zu Theenhausen,
• Polina Angelova and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2015, 6, 1712–1720, doi:10.3762/bjnano.6.175

• -thiol (BPT); (c) S,S'-(3',4',5',6'-tetraphenyl-[1,1':2',1''-terphenyl]-4,4''-diyl) diethanethioate (HPB); (d) naphtalene-2-thiol (NPTH); (e) 2-bromo-11-(1’-[4’-(S-acetylthiomethyl)phenyl]acetyl)-5,8,14,17-tetra(3’,7’-dimethyloctyl)-hexa-peri-hexabenzocoronene (HBC-Br). The CNMs in the presented figures

Conductance through single biphenyl molecules: symmetric and asymmetric coupling to electrodes

• Karthiga Kanthasamy and
• Herbert Pfnür

Beilstein J. Nanotechnol. 2015, 6, 1690–1697, doi:10.3762/bjnano.6.171

• groups like amine, nitro, nitrile, carboxy, iso cyanate, pyridine. The electron donating group leads to higher conductance while electron withdrawing groups have a smaller conductance. The Au–S thiol is a well known anchoring group due strong covalent bond coupling [15]. The iso cyano group has been

• of the asymmetric molecule with one thiol and one carbonitrile end group. This choice is motivated by two effects: Firstly, the interaction between thiol and gold electrodes is stronger than for the carbonitrile group [19]. Secondly, coupled with the details of bond formation is the fact that these

• two end groups have an opposite effect on the level alignment of the highest occupied (HOMO) and lowest unoccupied (LUMO) molecular levels [19][40]. While thiol tends to pull the HOMO up by shifting a small amount of charge to the molecule, the cyano group has the opposite effect. These properties may

Electrical properties and mechanical stability of anchoring groups for single-molecule electronics

• Riccardo Frisenda,
• Simge Tarkuç,
• Elena Galán,
• Mickael L. Perrin,
• Rienk Eelkema,
• Ferdinand C. Grozema and
• Herre S. J. van der Zant

Beilstein J. Nanotechnol. 2015, 6, 1558–1567, doi:10.3762/bjnano.6.159

• mechanically controlled break junction (MCBJ) technique. The four molecules studied share the same core structure, namely oligo(phenylene ethynylene) (OPE3), while having different aurophilic anchoring groups: thiol (SAc), methyl sulfide (SMe), pyridyl (Py) and amine (NH2). The focus of this paper is on the

• combined characterization of the electrical and mechanical properties determined by the anchoring groups. From conductance histograms we find that thiol anchored molecules provide the highest conductance; a single-level model fit to current–voltage characteristics suggests that SAc groups exhibit a higher

• -molecule junctions are formed if thiol (SH), methyl sulfide (SMe), pyridyl (Py) and amine (NH2), groups are used as anchoring groups [16][28][29][30]. In a comparative study Hong et al. [20], found that the low-bias conductance follows the trend SH > NH2> Py > CN by comparing a series of tolanes anchored

Peptide-equipped tobacco mosaic virus templates for selective and controllable biomineral deposition

• Klara Altintoprak,
• Axel Seidenstücker,
• Alexander Welle,
• Sabine Eiben,
• Petia Atanasova,
• Nina Stitz,
• Alfred Plettl,
• Joachim Bill,
• Hartmut Gliemann,
• Holger Jeske,
• Dirk Rothenstein,
• Fania Geiger and
• Christina Wege

Beilstein J. Nanotechnol. 2015, 6, 1399–1412, doi:10.3762/bjnano.6.145

• subunit [76] were chemically equipped with a dense peptide coating via succinimidyl ester-activated, bifunctional, PEG-based linkers, and their subsequent maleimide-mediated conjugation to thiol groups of terminal cysteine residues present in every peptide. Five different peptide sequences were selected

Nano-contact microscopy of supracrystals

• Adam Sweetman,
• Nicolas Goubet,
• Ioannis Lekkas,
• Marie Paule Pileni and
• Philip Moriarty

Beilstein J. Nanotechnol. 2015, 6, 1229–1236, doi:10.3762/bjnano.6.126

• qPlus probe became nanocrystal- (or thiol-)terminated. Imaging was performed in constant current STM, constant frequency shift (Δf) DFM, and constant height DFM modes. In addition to traditional STM, we also carried out dynamic STM (dSTM) imaging and spectroscopy, where the tip was oscillated with a

• intra-nanocrystal features is challenging for a number of reasons. First, the exact nature of our tip apex is unknown, and very possibly terminated either by free thiol ligands or entire nanocrystals. Second, due to the high aspect ratio of the nanocrystal surface (as compared to an atomically flat

• scenario where we have both a thiol-terminated tip and thiol-coated nanocrystal, and where the thiols on both the tip and nanocrystal would be relatively free to relax as the tip approaches the sample. These observations are also consistent with the numerous reconfiguration events that we observe during

Electrical characterization of single molecule and Langmuir–Blodgett monomolecular films of a pyridine-terminated oligo(phenylene-ethynylene) derivative

• Henrry M. Osorio,
• Santiago Martín,
• María Carmen López,
• Santiago Marqués-González,
• Simon J. Higgins,
• Richard J. Nichols,
• Paul J. Low and
• Pilar Cea

Beilstein J. Nanotechnol. 2015, 6, 1145–1157, doi:10.3762/bjnano.6.116

• other LB films), the conductance value for compound 1 is 3–20 times greater than for LB films of other oligo(phenylene-ethynylene) (OPE) derivatives bearing anchoring groups such as thiol (–SH), amine (–NH2), carboxylate (–COO−), trimethylsilylethynyl (–C≡CSiMe3) or acetylide (–C≡C) [23][24][30][45

• ]. Similar variations in conductance as a function of surface contacting group have been found for polymethylene (alkane) bridges contacted with thiol, amine or carboxylic acid moieties to gold electrodes [75]. The higher conductance for 1 could be attributed to both the shorter molecular length and

• anchoring group in metal–molecule–metal and metal–monolayer–metal junctions formed by LB methods. The data indicate that it exhibits a higher conductance when compared with other anchoring end groups used in OPE derivatives assembled by the LB technique such as thiol, amine, carboxylic acid

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

• electron donors such as thiol groups found on the negatively-charged sperm membrane [57][68]. Oligonucleotide-conjugated nanoparticles might bind directly to nucleic acid specific binding sites which have been shown to exist on the sperm surface [69]. The fact that BSA coating inhibits nanoparticle

• nanoparticles may lead to a decrease in motility (i) either by production of reactive oxygen species (ROS) or (ii) by binding to free thiols present on the sperm surface as gold nanoparticles posses a high affinity to thiol groups. The thiols on the sperm surface are part of membrane bound Na+/K+-ATPases and

Self-assembled anchor layers/polysaccharide coatings on titanium surfaces: a study of functionalization and stability

• Ognen Pop-Georgievski,
• Dana Kubies,
• Josef Zemek,
• Neda Neykova,
• Roman Demianchuk,
• Eliška Mázl Chánová,
• Miroslav Šlouf,
• Milan Houska and
• František Rypáček

Beilstein J. Nanotechnol. 2015, 6, 617–631, doi:10.3762/bjnano.6.63

• different organic compounds, providing functional groups for further modification. Covalent bonding, which provides a stable fixation of immobilized compounds, is an alternative approach to coatings based on adsorption processes. The most common strategies for the formation of anchoring layers are thiol

• -based self-assembled monolayers (SAMs) [20] and silanes [21][22]. Despite the ease of preparation and high uniformity of the resulting layers, the thiol–SAMs provide an anchoring chemistry scheme limited only to noble metals. Furthermore, the established thiol bond is prone to oxidation and can be

• -aminopropyltriethoxysilane (APTES) can result in several surface structures such as covalent attachment, self-assembly, multilayer formation by surface-initiated (SI) polymerization and particle adsorption [22]. The obstacles and limitations inherent to thiol–SAMs and silanes can be circumvented by the use of moieties

Synergic combination of the sol–gel method with dip coating for plasmonic devices

• Cristiana Figus,
• Maddalena Patrini,
• Francesco Floris,
• Lucia Fornasari,
• Paola Pellacani,
• Gerardo Marchesini,
• Andrea Valsesia,
• Flavia Artizzu,
• Daniela Marongiu,
• Michele Saba,
• Franco Marabelli,
• Andrea Mura,
• Giovanni Bongiovanni and
• Francesco Quochi

Beilstein J. Nanotechnol. 2015, 6, 500–507, doi:10.3762/bjnano.6.52

• serves to stabilize the sensing platform (as in the case of metal nanoparticles) and provides a specific affinity, resulting in improved selectivity [7][8][11][12]. Furthermore, the surface chemistry of thiol-based self-assembled monolayers has shown some limitations mainly related to their temporal

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

• cetyltrimetylammonium bromide (CTAB) in water. Furthermore, we investigated the effects of GNP that were linked to thiol-terminated polyethylene glycol (SH-PEG, MW of PEG: 5 kDa) with different reactive groups: cationic (-NH2), anionic (-COOH) or neutral (-OCH3). 2) Asymmetric Au@metal oxide nanoparticles have an

Mechanical properties of MDCK II cells exposed to gold nanorods

• Anna Pietuch,
• Bastian Rouven Brückner,
• David Schneider,
• Marco Tarantola,
• Christina Rosman,
• Carsten Sönnichsen and
• Andreas Janshoff

Beilstein J. Nanotechnol. 2015, 6, 223–231, doi:10.3762/bjnano.6.21

• (DNA, proteins, antibodies) with functional groups using self-assembly techniques relying on gold–thiol interaction. Since these NPs are engineered to interact with living cells it is essential to prove if there is no adverse impact on cell viability [5][10]. Prerequisite for successful medical

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

• -synuclein that contains an additional cysteine residue. The fibrils have been biotinylated via thiol groups and subsequently joined with neutravidin-conjugated gold nanoparticles. Atomic force microscopy and transmission electron microscopy confirmed the expected structure – nanoladders. The ability of

• ). Sulfhydryl-reactive, biotin maleimide was used to modify the free –SH groups. Biotinylation was performed in PBS buffer (pH 7.5) and a 5-fold molar excess of biotin reagent was added to the mixture. To remove the excess of biotin, the α-SynC141 fibril sample was dialyzed. The concentration of thiol groups in

• the samples, which depends on the modification step, was monitored using TNB reagent (Table 1). Less than 1% of free thiol groups were detected both in the initial solution of α-SynC141 and after the fibrillization. Notwithstanding that, the main fraction of the initial solution of α-SynC141 contained

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

• and characterization of fluorescent silica and ceria nanoparticles. Synthetic methods for labelling of silica and polyorganosiloxane/silica core–shell nanoparticles with perylenediimide derivatives are described, as well as the modification of the shell with thiol groups. Photometric methods for the

• determination of the number of thiol groups and an estimate for the number of fluorescent molecules per nanoparticles, including a scattering correction, have been developed. Ceria nanoparticles decorated with noble metals (Pt, Pd, Rh) are models for the decomposition products of automobile catalytic converters

• molecules are reasonably separated from each other without the danger of self-quenching of the fluorescence. During the process of formation of the primary shell one can easily modify the surface without influencing the fluorescent core. Thus, we introduced thiol (–SH) groups at or near the surface by

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

• parameters, such as switching to more polar solvents to compensate the electron deficiency for Au@Fe3O4 flowerlike particles [81], or for Au@MnO flowerlike particles in situ formation of gold particles without surface protection caused by thiol addition [58]. Phase-separated vs ternary-phase nanoparticles

• surface, only the metal oxide domain is encapsulated leaving the hydrophobic character of the gold domain untouched (Figure 15). This selectivity is enhanced due to the functionalization of the gold domain with a thiol, which can be performed either prior to the growth of manganese oxide or after

• formation of the iron oxide component. Wu et al. pointed out that a thiol passivation of the surface is crucial for retaining the Janus character due to the two different surfaces [38]. This was demonstrated by complete encapsulation of Au@Fe3O4 as well as Ag@Fe2O3 nanoparticles with a silica shell [103

Advanced atomic force microscopy techniques II

• Thilo Glatzel,
• Ricardo Garcia and
• Thomas Schimmel

Beilstein J. Nanotechnol. 2014, 5, 2326–2327, doi:10.3762/bjnano.5.241

• force microscopy [8] are presented as well as molecular structures such as the self-assembly of multidentate organothiols onto Au(111), which were studied in situ by using scanning probe nanolithography and time-lapse AFM [9]. Patterns of thiol-based self-assembled monolayers for the site-selective

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

• around the NPs, so that intrusion of proteins into the layer, which may happen with polymeric shells, can be excluded. Cysteamine molecules, which feature primary amine groups, were covalently bound to the QD surface via their thiol groups (see Experimental) to obtain positively charged QDs

• adsorption via the positive region on negatively charged QDs results in a radius increase of 3.2 nm; right: a corona thicker than 3.2 nm is generated by adsorption in a more random orientation. NP surface ligands employed in the present study. They associate with the CdSe/ZnS QD surface via their thiol group