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Search for "thiol" in Full Text gives 172 result(s) in Beilstein Journal of Nanotechnology.
Micro- and nano-surface structures based on vapor-deposited polymers
Beilstein J. Nanotechnol. 2017, 8, 1366–1374, doi:10.3762/bjnano.8.138
- microstructures of PEG hydrogels [22]. In a separate report, this photodefinable polymer was used to pattern protein molecules using a photomask-assisted lithographical approach [23]. Recently, surface patterns were enabled via light-induced thiol-ene/thiol-yne reactions on a poly(4-vinyl-p-xylylene-co-p-xylylene
- initiated CVD system [75]. The route-controlled click reactions, including a thiol-yne reaction and a copper-free alkyne/azide click reaction, were enabled to create continuous and reverse gradients on a CVD deposited poly[(4-methylpropiolate-p-xylylene)-co-(p-xylylene)] surface. The two-click reactions
Triptycene-terminated thiolate and selenolate monolayers on Au(111)
Beilstein J. Nanotechnol. 2017, 8, 892–905, doi:10.3762/bjnano.8.91
- selenoacetate Trp1SeAc (compare Scheme S1 in the Supporting Information File 1). Selenoacetate compounds can be used to form selenolate SAMs on gold surfaces [8]. Earlier work on homologous sulfur compounds revealed that free thiol groups are incompatible with benzyne [28]. Yet, it could be shown that formation
- of the triptycene group by reaction of anthracene moieties with benzyne is possible if the sulfur atom is protected, e.g., with an acyl group [28]. We suspected the selenol group to be similarly unstable towards benzyne as the thiol group and thus aimed to protect it. For this purpose, 9
Selective detection of Mg2+ ions via enhanced fluorescence emission using Au–DNA nanocomposites
Beilstein J. Nanotechnol. 2017, 8, 762–771, doi:10.3762/bjnano.8.79
- modifications in the plasmonic spectra. The biophysical properties of DNA make it compatible for linkage with metals, which are useful in a variety of applications such as biosensor development. They can also be stabilized with a wide variety of molecules because of the alkyl thiol adsorption phenomena [3
- . Here, MPA helps both in the stabilization as well as thiol functionalization. MPA can easily stabilize the AuNPs due to the strong affinity of sulphur groups for gold. Also, the thiolated-DNA can directly bind to the surface of AuNPs by thiol–Au interactions [39][40]. Before use, DTT (0.1 M DTT, 10 mM
α-((4-Cyanobenzoyl)oxy)-ω-methyl poly(ethylene glycol): a new stabilizer for silver nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 627–635, doi:10.3762/bjnano.8.67
- metal nanoparticles that is based on a cyano rather than a thiol or thiolate anchor group. The silver particles used to evaluate the effectiveness of the new stabilizer typically have a bimodal size distribution with hydrodynamic diameters of ca. 13 and ca. 79 nm. Polymer stability was evaluated as a
- suggesting that α-((4-cyanobenzoyl)oxy)-ω-methyl poly(ethylene glycol) is a good stabilizer for metal nanoparticles in aqueous media unless very high pH conditions are present in the system. The study thus demonstrates that cyano groups can be viable alternatives to the more conventional thiol/thiolate
- oligomeric or polymeric stabilizer is attached to the particle surface without a specific anchor group [26][27][28][29][30]. The current gold standard for anchoring an organic moiety on the NP surface is the thiol or thiolate group [3][24][31][32][33]. There are, however, cases where the thiol group may not
Gas sensing properties of MWCNT layers electrochemically decorated with Au and Pd nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 592–603, doi:10.3762/bjnano.8.64
- that a high gold content enhances the gas sensor response, thanks to the great affinity between gold and sulfur atoms of thiol groups [50]. Therefore, the increase in the Au NP density enhances the amount of the adsorption sites for H2S, resulting in a higher sensitivity and selectivity towards H2S gas
Comparison of four methods for the biofunctionalization of gold nanorods by the introduction of sulfhydryl groups to antibodies
Beilstein J. Nanotechnol. 2017, 8, 372–380, doi:10.3762/bjnano.8.39
- methods for the introduction of thiol groups onto the surface of GNRs by using Traut’s reagent, dithiotreitol (DTT), dithiolaromatic PEG6-CONHNH2, and thiol-polyethylene glycolamine (SH-PEG-NH2) combined with EDC reaction. We showed that the four above-mentioned thiolation methods can efficiently
- EDC reaction may affect the amount of functionalized GNRs because of the efficiency of thiol moiety linkage to antibodies, thereby affecting the sensitivity of the GNR sensor. The introduction of a thiol group to antibodies by using Traut’s reagent, DTT, and PEG6-CONHNH2 allowed for direct
- solution and the CTAB bilayer density [15]. The common ligand exchange is the replacement of the CTAB of GNR with thiol-terminated ligands, such as thiolated poly(ethylene glycol) and mercaptoundecanoic acid [10][11]. These agents can link the amino groups of biomolecules with the carboxylic group from
Comparison of four functionalization methods of gold nanoparticles for enhancing the enzyme-linked immunosorbent assay (ELISA)
Beilstein J. Nanotechnol. 2017, 8, 244–253, doi:10.3762/bjnano.8.27
- ). Afterwards, the appropriated amount of Ab-linker and HRP-linker were mixed with 1 mL of AuNPs and incubated for 20 min. Thereafter, 100 μg of m-PEG thiol were added and mixed again for 20 min. Subsequently, 100 µL of 1 mg/mL of BSA were incubated for 10 min more. Samples were centrifuged (5,000g 30 min) and
- complex concentration was measured by absorption at 520 nm and kept at 4 °C until use. Covalent functionalization was achieved using hetero-bifunctional linkers of polyethyleneglycol (PEG). In this case, AuNPs were incubated overnight with methyl-PEG-thiol (mPEG thiol, n = 6) and PEG-thiol acid (n = 7) in
- order to create a mixed monolayer of linker on the nanoparticle. 1 mL containing 0.075 M of mPEG thiol and 0.025 M of PEG-thiol acid was added to 100 mL of synthetized AuNPs and maintained overnight under stirring. Subsequently, the AuNPs were washed by centrifugation at 18,000g for 30 min and the
Performance of colloidal CdS sensitized solar cells with ZnO nanorods/nanoparticles
Beilstein J. Nanotechnol. 2017, 8, 210–221, doi:10.3762/bjnano.8.23
- nanoparticle aggregation. Various disulfide bonds, thiol residues and other hydroxyl moieties that exist on BSA can serve as effective surface functionalized groups on CdS surfaces [27]. This may further lead to better anchoring with the metal oxide-based photoanode. Among the alternative single oxide
Impact of surface wettability on S-layer recrystallization: a real-time characterization by QCM-D
Beilstein J. Nanotechnol. 2017, 8, 91–98, doi:10.3762/bjnano.8.10
- introduction of a terminal sulfhydryl group by modification with 2-iminothiolane was performed [3]. Subsequently, thiol–secondary cell-wall polymer (thiol-SWCP) was used to activate gold surfaces, either QSX301 gold sensors (4.95 MHz, QSense AB, Sweden) by means of peristaltic pumping (SM935C, Ismatec, Zürich
- , Switzerland), in QCM-D, or commercial flat gold ArrandeeTM chips (Arrandee Metal GmbH, Germany) by immersion into a petri-dish filled with thiol-SCWP solution for AFM measuring purposes. After one hour of incubation we obtained a SCWP surface for S-protein recrystallization. Methods Atomic force microscopy
- with nitrogen. All images were processed with the Nanoscope program. Quartz crystal microbalance with dissipation (QCM-D): QCM-D experiments were performed in a Q-Sense E4 instrument (Q-Sense AB, Sweden). Prior to their use, gold-coated quartz sensors (for thiol–SCWP binding) were sonicated in 2% (w/w
Surface-enhanced Raman scattering of self-assembled thiol monolayers and supported lipid membranes on thin anodic porous alumina
Beilstein J. Nanotechnol. 2017, 8, 74–81, doi:10.3762/bjnano.8.8
- -3-phospho-L-serine (POPS) and, 1,2-dioleoyl-3-trimethylammoniumpropane (DOTAP), from Avanti Polar Lipids (Alabaster, Alabama, US). All solvents were purchased from Sigma-Aldrich. First, the substrates were incubated at rt for 2 h with a 1 mM aqueous solution of the thiol molecule, either MbA or AT
- unilamellar vesicles. Preparation of the Raman target analytes: SLBs The lipid vesicles were diluted to 0.5 g/L in the PBS buffer and vortexed immediately before use. The thiol SAM was incubated overnight with the lipid vesicle dispersion, to allow vesicle physisorption and fusion onto the substrate. The
- living cells, where they would adhere to the nanoporous substrate. SERS enhancement due to tAPA–Au on thiols, lipids, and thiol–lipid systems The Raman measurements were performed first on the thiol molecules. We started from the raw materials, in powder form, to obtain reference spectra for future
Streptavidin-coated gold nanoparticles: critical role of oligonucleotides on stability and fractal aggregation
Beilstein J. Nanotechnol. 2017, 8, 1–11, doi:10.3762/bjnano.8.1
- further studies on oligodeoxyribonucleotide (ODN)-functionalized SA-conjugated AuNPs. SA-conjugated AuNPs have not been so widely studied as thiol-conjugated AuNPs. Nevertheless, ODN-functionalized SA-conjugated AuNPs are largely used for different purposes including biosensing [15][16][17]. Results from
- . The data shown here demonstrate that the electrostatic repulsion provided by the negatively charged ODN moieties contributes to the final AuNP stabilization against aggregation, as already reported for thiol-mediated conjugation of citrate-stabilized AuNPs [18][19]. In addition, it is demonstrated
Solvent-mediated conductance increase of dodecanethiol-stabilized gold nanoparticle monolayers
Beilstein J. Nanotechnol. 2016, 7, 2057–2064, doi:10.3762/bjnano.7.196
- solution containing conjugated thiol-functionalized molecules. Typically, this observation is attributed to molecular exchange. Less attention has been paid to the role of the solvent alone. Here, we report on an increase in conductance of dodecanethiol-stabilized gold nanoparticle monolayers on Si/SiO2 by
A novel electrochemical nanobiosensor for the ultrasensitive and specific detection of femtomolar-level gastric cancer biomarker miRNA-106a
Beilstein J. Nanotechnol. 2016, 7, 2023–2036, doi:10.3762/bjnano.7.193
- strategies such as using the thiol group, particle functionalization, and streptavidin–biotin interaction. Streptavidin has an extraordinary high affinity for biotin and the streptavidin–biotin bond is one of the strongest non-covalent interactions known in nature (with a dissociation constant in the order
Functionalized platinum nanoparticles with surface charge trigged by pH: synthesis, characterization and stability studies
Beilstein J. Nanotechnol. 2016, 7, 1822–1828, doi:10.3762/bjnano.7.175
- investigated. PtNPs were obtained by a wet redox procedure using 2-diethylaminoethanethiol hydrochloride (DEA) as capping agent. By varying the Pt/thiol molar ratio, monodispersed and stable particles with diameters in the range of 3–40 nm were isolated. The amino functionality allows neutral particles to be
- colloidal system. Keywords: functionalized platinum nanoparticles; pH responsive materials; synthesis of metal nanoparticles; thiol functionalization; Introduction Metal nanoparticles (MNPs), in particular, platinum nanoparticles (PtNPs) offer a wide range of chemico-physical properties that can be of
- colloidal stability; hydrophobic or hydrophilic thiol-based ligands have been deeply exploited [14][15]. Among others, 2-diethylaminoethanethiol hydrochloride (DEA) has been used as a stabilizing thiol for gold nanoparticles used for the immobilization of lipase [16]. Among others, hydrothermal and
Hydrophilic silver nanoparticles with tunable optical properties: application for the detection of heavy metals in water
Beilstein J. Nanotechnol. 2016, 7, 1654–1661, doi:10.3762/bjnano.7.157
- nitrate as precursor molecules, hydrophilic thiol (3-mercapto-1-propanesulfonic acid sodium salt, 3MPS) and sodium borohydride as capping and reducing agents, respectively. The AgNPs were characterized using techniques such as surface plasmon resonance (SPR) spectroscopy, dynamic light scattering (DLS
- synthesis AgNPs were synthesized by wet reduction, using sodium borohydride as a reducing agent and 3-mercapto-1-propanesulfonic acid sodium salt as a capping agent. The water solubility of the thiol induces a strongly hydrophilic character with respect to the nanoparticles, which present the sulfonate
Photothermal effect of gold nanostar patterns inkjet-printed on coated paper substrates with different permeability
Beilstein J. Nanotechnol. 2016, 7, 1480–1485, doi:10.3762/bjnano.7.140
- printing because of their conductive and thermal properties [1][8]. Within the existing types of metal nanoparticles, the beneficial properties of gold, such as good biocompatibility, excellent resistance to oxidation and acids, and high affinity to thiol containing biomolecules promote the applicability
- this factor is studied in this letter. Therefore, GNS with well-controlled structure and with LSPR centred at about 760 nm were synthesized, decorated with poly(ethylene glycol) thiol (PEG-SH) [18], and inkjet-printed onto three differently coated paper substrates at various drop density values (δ
Straightforward and robust synthesis of monodisperse surface-functionalized gold nanoclusters
Beilstein J. Nanotechnol. 2016, 7, 1278–1283, doi:10.3762/bjnano.7.118
- reduction of HAuCl4 with citrate at high temperatures [21], sodium borohydride can act as a reducing agent while an alkanethiol stabilizes the nanoparticles [22]. The latter method was used to prepare glyconanoparticles by adding thiol-terminated glycoconjugates [23]. Gold nanoparticles have also been
Tunable longitudinal modes in extended silver nanoparticle assemblies
Beilstein J. Nanotechnol. 2016, 7, 1219–1228, doi:10.3762/bjnano.7.113
- temperatures. These robust AgNPs assemblies are comparably thermally resistant to previously described self-assembled gold nanoparticles [38] allowing for a broader blue-shifted bimodal optical tuning of plasmonic assemblies. To further examine the influence of hydrogen bonding on the assembly, the thiol and
Dielectrophoresis of gold nanoparticles conjugated to DNA origami structures
Beilstein J. Nanotechnol. 2016, 7, 948–956, doi:10.3762/bjnano.7.87
- a thiol functionality at the 3′ end (sequence: 5′TTTTT TTTTT TTTTT TTT–C3H5SH3′, HPLC purified, Biomers.net). For this, 3.2 pmol phosphinated gold nanoparticles were mixed in equivalent ratio with the oligonucleotides in Na+-TBE buffer solution (50 mM NaCl, 89 mM Tris, 89 mM boric acid, 1 mM EDTA pH
Gold nanoparticles covalently assembled onto vesicle structures as possible biosensing platform
Beilstein J. Nanotechnol. 2016, 7, 655–663, doi:10.3762/bjnano.7.58
- per-6-thio-β-cyclodextrin accomplished via covalent gold–thiol bonds [10]. These AuNPs provide an excellent platform for drug delivery due to the functional versatility of their monolayers. The vesicles with AuNPs are suitable for applications such as transport inside cells [11], photodynamic
- systems were around 175 nm with a polidispersity of 0.2 determined by DLS indicating that the size of the LUVs does not change significantly by the incorporation of SH to the bilayer. A question may arise here about the orientation of the thiol molecules in the bilayer. That is, whether there are thiol
- was exposed and immersed in the SH–DOPC LUV solution for 30 min, enough time to form bonds between AuE and SH/DOPC [25]. This procedure was carried out in order to covalently bond the vesicles on the AuE through the thiol incorporated in the bilayer. Then, the AuE modified with SH–DOPC LUVs was
Novel roles for well-known players: from tobacco mosaic virus pests to enzymatically active assemblies
Beilstein J. Nanotechnol. 2016, 7, 613–629, doi:10.3762/bjnano.7.54
- variants and solid supports, in some cases involving thiol bonding ([7][173] and references therein; [110][174][175][176]). So far, however, it remains to be tested whether TMV particles immobilized via protruding RNA ends or through non-covalent attachment would retain their arrangement inside the flow
Comparison of the interactions of daunorubicin in a free form and attached to single-walled carbon nanotubes with model lipid membranes
Beilstein J. Nanotechnol. 2016, 7, 524–532, doi:10.3762/bjnano.7.46
- controlled way [21][22]. Due to the presence of a thiol group in the polar headgroup region, this lipid has negative charge and it is possible to transfer monolayers onto solid support by means of both Langmuir–Blodgett method and self-assembly, which results in the differences in the packing of the
Rigid multipodal platforms for metal surfaces
Beilstein J. Nanotechnol. 2016, 7, 374–405, doi:10.3762/bjnano.7.34
- . Since the early stages of molecular electronics, most studies deal with molecules attached to the gold surface through one thiol (–SH) group [63]. While the details of the adsorption mechanism are still under debate, it is commonly considered that the hydrogen of the thiol group is eliminated in contact
- with gold and that a covalent Au–S bond is formed [23][64]. This bond has a dissociation energy of around 2.1 eV (ca. 50 kcal·mol−1), which is large enough to ensure the thermal stability of thiol monolayers up to 80 °C [65]. Furthermore, it is stronger than the Au–Au bond with a dissociation energy of
- around 0.8 eV [66], which can lead to the removal of small gold clusters by mechanically removing thiols. The versatility of the thiol anchoring guarantees a dense coverage of both flat and rough gold surfaces. The clean close packed Au(111) surface exhibits a hexagonal arrangement of atoms with a well
Hemolysin coregulated protein 1 as a molecular gluing unit for the assembly of nanoparticle hybrid structures
Beilstein J. Nanotechnol. 2016, 7, 351–363, doi:10.3762/bjnano.7.32
- connection via gold–thiol binding. The Au NP network shows similar reactivity to the colloidal Au NPs as a catalyst in the reduction reaction of 4-nitrophenol to 4-aminophenol. To explore the broad application of our concept, Hcp1_cys3 is also applied to assemble Fe3O4 and CoFe2O4 NPs. The reaction is
Case studies on the formation of chalcogenide self-assembled monolayers on surfaces and dissociative processes
Beilstein J. Nanotechnol. 2016, 7, 263–277, doi:10.3762/bjnano.7.24
- . We discuss some recent studies based on X-ray photoelectron spectroscopy that shed light on these aspects for a series of such organic molecules. Keywords: copper; nickel; palladium; reactivity; selenol; selenophene; self-assembly; thiol; thiophene; Introduction In recent years research related to
- head group (thiol) molecules [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27], but interest in other head group atoms such as C [28][29], N [30] and other chalcogenides has also received increased attention. In particular, selenium head group SAMs have
- transition metal surfaces [44][45]. A few years ago, the research groups of Nuzzo [46], Whitesides [46] and others [48] noted that for alkane thiol SAMs, the initial desulfurization occurs via S–C bond scission. This leads to the formation of a sulfidic interface layer, upon which a more or less ordered
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