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Search for "thiol" in Full Text gives 172 result(s) in Beilstein Journal of Nanotechnology.
Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications
Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64
- ) and assessed their effect on human glioblastoma (U-87 MG) cells under US exposure at a frequency of 1 MHz. In this study, thiol–maleimide was used to cross-link the DOX-containing liposomes onto the surface of the MBs. The in vitro results showed a four-fold enhancement in cell death using DOX
Silver nanoparticles nucleated in NaOH-treated halloysite: a potential antimicrobial material
Beilstein J. Nanotechnol. 2021, 12, 798–807, doi:10.3762/bjnano.12.63
- behaviour is most certainly due to the presence of DIO, a very hydrophobic substance itself. DIO is an organic molecule made of a long carbon chain “tail” attached to a thiol “head” (R-SH), which forms covalent bonds with silver via the sulfur atom. So, by mixing DIO and Ag/HNT-8 one is able to create a
Fate and transformation of silver nanoparticles in different biological conditions
Beilstein J. Nanotechnol. 2021, 12, 665–679, doi:10.3762/bjnano.12.53
- are created by several pathways, including partial AgNPs dissolution in the gastric fluid, uptake and systemic transport of ionic and nanoparticulate Ag as thiol and selenium complexes, and final deposition in the near-skin regions [15]. Especially important is the process of interaction with thiols
- owing to their many physiological roles and evidences for thiol-containing proteins as major targets for toxic effects of ionic Ag [25]. In the presence of biothiols the soluble complexes are formed. Thiols possess a high affinity for soft Lewis acid metals and may easily coordinate Ag+ [9][26][27]. The
- association of Ag with sulphur and the formation of Ag2S granules from ion exchange or Ag–thiol complexes is known as sulphidation [28][29]. However, many other scenarios should be considered during an in vivo journey of AgNPs and Ag+ ions, especially their interactions with biomolecules, such as lipids
On the stability of microwave-fabricated SERS substrates – chemical and morphological considerations
Beilstein J. Nanotechnol. 2021, 12, 541–551, doi:10.3762/bjnano.12.44
- by utilizing a thiol-functionalized test molecule to form a defined monomolecular dense layer of analyte on the surface. Additionally, 4-ATP only binds to silver nanoparticles and does not bind to the underlying glass substrate. The self-assembly time for 4-ATP solutions was kept short to avoid any
A review on nanostructured silver as a basic ingredient in medicine: physicochemical parameters and characterization
Beilstein J. Nanotechnol. 2021, 12, 440–461, doi:10.3762/bjnano.12.36
- agents responsible for the toxicity of silver and argyria in our body. When Ag+ enters the bloodstream, it is transported bound to albumin and thiol groups. When it reaches a region close to the skin, in areas affected by light, it can easily be photoreduced to AgNPs, which are then immobilized in the
- epidermis. Immobilization is both physical, due to the low diffusivity of the particles, and chemical, since thiol-exchange reactions occur with Ag+ but not with AgNPs. This fact explains why AgNPs are not responsible for causing argyria or argyrosis [1][11]. It is well known that the strong interaction of
- from the damaged respiratory chain since they depend on thiol groups which are occupied by silver ions. The increase in superoxide and hydrogen peroxide anions in the reaction with iron (Fenton reaction), according to Equation 2 [104] and as described in Figure 6, are indicative of the deleterious
Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing
Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26
- beam-induced surface activation (EBISA) are studied with the precursors Fe(CO)5 and Co(CO)3NO on SAMs of 1,1′,4′,1′′-terphenyl-4-thiol (TPT). For Co(CO)3NO only EBID leads to deposits consisting of cobalt oxide. In the case of Fe(CO)5 EBID and EBISA yield deposits consisting of iron nanocrystals with
- aromatic molecules, which are chemically bound to a Au or Ag surface via either thiol [26] or carboxylic [28][29] anchor groups. Via FEBIP, the SAM can be functionalized with metallic nanostructures and subsequently be transformed into a CNM by electron-induced cross-linking. Afterwards, the resulting
- metallic nanostructures fabricated via EBID and Fe(CO)5 remain unchanged, besides oxidation. This result was achieved by using a SAM consisting of 1,1′,4′,1′′-terphenyl-4-thiol (TPT) on a Au substrate [21]. In this work, we want to gain more insight into the underlying processes yielding such hybrid
Characterization, bio-uptake and toxicity of polymer-coated silver nanoparticles and their interaction with human peripheral blood mononuclear cells
Beilstein J. Nanotechnol. 2021, 12, 282–294, doi:10.3762/bjnano.12.23
- . RPMI medium contains chloride, which can lead to reprecipitation of Ag ions as described previously [37]. Furthermore, cysteine and thiol-containing proteins are found in FBS and have a high affinity for Ag ions and NPs. Ag loss to the container wall could be another reason that we did not get full
Fusion of purple membranes triggered by immobilization on carbon nanomembranes
Beilstein J. Nanotechnol. 2021, 12, 93–101, doi:10.3762/bjnano.12.8
- electron irradiation-induced cross-linking of a self-assembled monolayer (SAM) of 4′-nitro-1,1′-biphenyl-4-thiol (NBPT) and second, purple membrane (PM) containing genetically modified bacteriorhodopsin (BR) carrying a C-terminal His-tag. The NBPT-CNM was further modified to carry nitrilotriacetic acid
- optical properties as well as their chemical [39], thermal [40], and mechanical stability [41]. PM patches were deposited by electrophoretic sedimentation from a suspension as a quasi-monolayer on a 4′-nitro-1,1′-biphenyl-4-thiol (NBPT) CNM [42][43]. We use the term quasi-monolayer to express that there
- -thiol in dried and degassed N,N-dimethylformamide (DMF, anhydrous, 99.8%, Sigma-Aldrich) under nitrogen atmosphere in a sealed flask for 72 h, followed by subsequent rinsing with DMF (BioSyn, ≥99.9%, Honeywell) and absolute ethanol. Cross-linking of the SAMs was conducted by exposing the SAM to 100 eV
Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action
Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129
- interact with the functional groups of proteins and nucleic acids, such as thiol (–SH), amino (–NH), and carboxyl (–COOH) groups, and therefore, might affect the enzymatic activities and several protein structures. Although the metal ions released are not the main source of damage caused by NPs, it is
Ultrasensitive detection of cadmium ions using a microcantilever-based piezoresistive sensor for groundwater
Beilstein J. Nanotechnol. 2020, 11, 1242–1253, doi:10.3762/bjnano.11.108
- structure with thickness, FESEM image, PCB, and the experimental platform is shown in Figure 1. For using the microcantilever device for selectively detecting Cd(II) a surface modification is required. The surface modification of the sensor is basically a selective thiol coating on top of a gold surface
- . Results of the SAM detecting cadmium ions The proposed microfluidic platform provides real-time monitoring of Cd(II) in groundwater. We performed the experiment using the coating of cysteamine thiol with cross-linked ᴅʟ-glyceraldehyde (Cys-DL-GC). We have already discussed that the methods based on Au/Ag
- solution of cysteamine ([Cys] = 10 mM/10 mL) was prepared. The piezoresistive devices were gently dipped into a petri-dish containing cysteamine thiol for at least 12–24 hours. Longer times yield a better packing density of the SAM. In addition, a 2% (0.2 g/10 mL) solution of ᴅʟ-glyceraldehyde (DL-GC) in
Photothermally active nanoparticles as a promising tool for eliminating bacteria and biofilms
Beilstein J. Nanotechnol. 2020, 11, 1134–1146, doi:10.3762/bjnano.11.98
- thiol monolayers, aiming to impart a different wettability to the surfaces [63]. It was verified that the photothermal features and the consequent hyperthermia-derived antibacterial effects were not affected by the thiol layers, which enable the eradication of at least 99.99% of the bacterial strains
Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements
Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94
- positive charge of the amine groups. The uptake was determined to be proportional to the number of amine groups [84]. If the amine groups were exchanged with carboxyl or thiol groups, the activity was reduced and cells did not internalize as many nanoparticles [86]. In vivo tests also showed that PVA
Highly sensitive detection of estradiol by a SERS sensor based on TiO2 covered with gold nanoparticles
Beilstein J. Nanotechnol. 2020, 11, 1026–1035, doi:10.3762/bjnano.11.87
- previously isolated by the SELEX process by Kim and co-workers [17]. It was purchased from Eurogenetec with the following 76-mer-long sequence SH-C6-5′-GCT-TCC-AGC-TTA-TTG-AAT-TAC-ACG-CAG-AGG-GTA-GCG-GCT-CTG-CGC-ATT-CAA-TTG-CTG-CGC-GCT-GAA-GCG-CGG-AAG-C-3′. The thiol group was added to the 5′ end of the
- aptamer for functionalization via a Au–S bond. The aptamer was diluted and aliquoted upon arrival and stored at −18 °C. Sample functionalization MBA was used as a common Raman reporter to find out the best deposition parameters for Raman scattering enhancement. The thiol group is known to have a strong
- substrates, MBA was used as it is a well-known Raman reporter, showing two intense characteristic peaks at 1080 and 1590 cm−1 from aromatic ring vibrations [30]. The structure of MBA and the grafting process (thiol–gold interaction) guarantee that the molecule will preferentially attach to gold [37][38]. The
Silver-decorated gel-shell nanobeads: physicochemical characterization and evaluation of antibacterial properties
Beilstein J. Nanotechnol. 2020, 11, 620–630, doi:10.3762/bjnano.11.49
- layer producing silver nanoparticles but also transforms a fraction of sulfonic groups in the polymer to moieties with sulfur in a lower oxidation state, likely thiols. It is hypothesized that the generated thiol groups are anchoring the nanoparticles in the gel shell of the nanobeads stabilizing the
- have been partially reduced to thiol moieties. In consequence, the thiols interact with the silver nanoparticles anchoring them in the gel layer on the nanobeads. Moreover, it has been shown that the nanocomposite exhibits considerable antibacterial activity, comparable or superior to that of non
- reduced to a thiol moiety [37]. If this is the case, it may be hypothesized that the generated thiols adsorb on the surface of the silver nanoparticles (the adsorption of thiols on silver surfaces is a well-known phenomenon). It should be noted, however, that the binding energy of sulfur in aromatic
Luminescent gold nanoclusters for bioimaging applications
Beilstein J. Nanotechnol. 2020, 11, 533–546, doi:10.3762/bjnano.11.42
- , semiconductor quantum dots suffer from toxicity and are susceptible to oxidation. In this context, atomically precise gold nanoclusters protected by thiol monolayers have emerged as a new class of luminescent nanomaterials. Low toxicity, bioavailability, photostability as well as tunable size, composition, and
- play an important role in the luminesce properties of NCs [48][55]. For example, a phenylethane thiol (PET)-capped organically soluble Au25 nanocluster (Au25PET18) showed similar behavior as Au25NCs capped with long-chain alkanes [59]. However, it was shown that by choosing the appropriate surface
- of gold nanoclusters. A) Nanoclusters provide a link between molecular complexes and plasmonic nanoparticles. B) X-ray structure of [Au25(PET)18], from CSD entry JACVOB. C) Chemical structure of some of the organic thiols discussed in this review (PET: phenylethane thiol; LA: lipoic acid; GSH
Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery
Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41
- ), is a reversible reaction between different types of diene and dienophile resulting in thermo-responsive products. A fourth type, the thiol-ene reaction, is a reaction between thiol and alkene groups in the presence of a radical source as catalyst. The radicals can be generated through light, thermal
- . Other click chemistries like thiol-ene have also been reported because of their light-initiated and metal-catalyst-free approach. PVP along with PMA functionalized by thiol (PMAThiol) and ene (PMAEne) groups were used to fabricate hydrogen bonded hollow capsules via UV crosslinking [100]. It was further
- use of UV light in the thiol-ene approach limits its application in drug delivery as it can damage DNA and cross-react with cysteine residues in proteins. The DAC approach may also affect cysteine residues in proteins that might undergo Michael addition to result in malemides [90]. Similarly, the use
Preparation and in vivo evaluation of glyco-gold nanoparticles carrying synthetic mycobacterial hexaarabinofuranoside
Beilstein J. Nanotechnol. 2020, 11, 480–493, doi:10.3762/bjnano.11.39
- the antibodies generated against Ara6-GNPs would recognize the natural saccharides on the cell surface of different mycobacterial strains. For the preparation of glyco-GNPs, glycans are usually transformed to glycosides with thiol-functionalized spacer aglycons that are conjugated [43][44] either with
- pre-formed citrate-stabilized GNPs [67] or during the in situ synthesis of glyco-GNPs [32][38][46]. It is also possible to conjugate suitably derivatized glycans [48] via additional functional groups of thiol-functionalized ligands attached to the surface of pre-formed GNPs. We, however, chose an
- penetrate into the cells and can be used as carriers [83]. It has been demonstrated that the amine–gold surface interaction is charge-neutral and the stability of amine-capped GNPs is a finite-size effect, which is largely kinetic in origin, unlike that of thiol-capped GNPs, which are known to possess
Internalization mechanisms of cell-penetrating peptides
Beilstein J. Nanotechnol. 2020, 11, 101–123, doi:10.3762/bjnano.11.10
- -siRNA/miRNA delivery [17]. It has been reported that CPP-siRNA conjugates have reduced transient and stable expression of reporter transgenes in a number of mammalian cell lines [18]. In this case, thiol-containing siRNAs were synthesized and conjugated to penetratin or transportan by a reducible
Fully amino acid-based hydrogel as potential scaffold for cell culturing and drug delivery
Beilstein J. Nanotechnol. 2019, 10, 2579–2593, doi:10.3762/bjnano.10.249
- concentration of the elastically active chain were determined. After reduction of the disulfide bonds of CYS, the presence of thiol side groups was also detected. To determine the concentration of the reactive cross-linkers in the hydrogels, a new method based on the examination of the swelling behavior was
- established. Using metoprolol as a model drug, cell proliferation and drug release kinetics were studied at different LYS contents and in the presence of thiol groups. The optimal ratio of cross-linkers for the proliferation of periodontal ligament cells was found to be 60−80% LYS and 20−40% CYS. The
- untransformed cells. In the present study, derivatives based exclusively on amino acids, namely, on lysine-methylester (LYS) and CYS, were used as cross-linkers for preparing PASP-based hydrogels. CYS is biologically active and can provide free thiol groups under reductive conditions, while the advantage of LYS
Long-term stability and scale-up of noncovalently bound gold nanoparticle-siRNA suspensions
Beilstein J. Nanotechnol. 2019, 10, 2568–2578, doi:10.3762/bjnano.10.248
- structures usually consists of a AuNP, where siRNA is covalently bound to the NP surface through the thiol group, and the core is covered with a lipid or polymer shell [10][11][12][13]. Covalent bonding of siRNA to the surface of AuNPs is carried out in two stages: (1) covalent attachment of one chain of a
Bombesin receptor-targeted liposomes for enhanced delivery to lung cancer cells
Beilstein J. Nanotechnol. 2019, 10, 2553–2562, doi:10.3762/bjnano.10.246
- manner – a key feature of a targeting ligand to enable high tumour localisation. Formulation of a GRP-targeted liposomal carrier Having validated GRPR as a functional target on the surface of SCLC cells we next prepared a targeted liposomal carrier. The presence of a single thiol group in the cystabn
- peptide affords facile functionalisation of DSPE-PEG2000-maleimide thorough thiol coupling chemistry. Successful conjugation of the peptide was confirmed by MALDI–TOF mass spectrometry (Figure 2a,b). The most abundant mass peak of DSPE-PEG2000-cystabn (calculated mass: 4137.41 Da, assuming perfect
Evaluation of click chemistry microarrays for immunosensing of alpha-fetoprotein (AFP)
Beilstein J. Nanotechnol. 2019, 10, 2505–2515, doi:10.3762/bjnano.10.241
- sensitive fluorescent immunosensor for AFP detection. Three types of functionalized glasses (dibenzocyclooctyne- (DBCO-), thiol- and epoxy-terminated surfaces) were biotinylated by employing the respective adequate click chemistry counterparts (biotin–thiol or biotin–azide for the first class, biotin
- –maleimide or biotin–DBCO for the second class and biotin–amine or biotin–thiol for the third class). The anti-AFP antibody was immobilized on the surfaces via a biotin–streptavidin–biotin sandwich technique. To evaluate the sensing performance of the differently prepared surfaces, fluorescently labeled AFP
- –biotin sandwich strategy as well as the high selectivity of antigen–antibody interactions. Six different fabrication routes based on dibenzocyclooctyne- (DBCO-), thiol- and epoxy-functionalization of glasses and click chemistry attachment of biotinylated molecules (Figure 1) were used to obtain
Mobility of charge carriers in self-assembled monolayers
Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235
- of charge carriers has been observed in field-effect transistors (FET) made from this compound [32]. Anthracene-2-thiol, obtained by functionalization of anthracene with a thiol group, was used to fabricate SAMs on the top of Au bottom electrodes, which resulted in a beneficial effect on the
- thiol, we used the nanografting technique introduced by G.-y. Liu et al. [37]. HDT was used as the insulating thiol to decouple the PAT islands. Starting from a high quality PAT SAM, in well-defined PAT areas the OSC-based thiol was replaced by HDT using nanografting carried out in a liquid cell of an
- a function of island diameter. The black line shows the result of a fit in the diameter interval 20–160 nm by using Equation 1. a) Simple model of resistance within a single thiol molecule on the gold(111) surface. b) Model of charge transfer within a continuous SAM. The number of parallel resistors
Multiwalled carbon nanotube based aromatic volatile organic compound sensor: sensitivity enhancement through 1-hexadecanethiol functionalisation
Beilstein J. Nanotechnol. 2019, 10, 2364–2373, doi:10.3762/bjnano.10.227
- temperature toluene and benzene sensor based on multiwall carbon nanotubes (MWCNTs) decorated with gold nanoparticles and functionalised with a long-chain thiol self-assembled monolayer, 1-hexadecanethiol (HDT). High-resolution transmission electron microscopy (HRTEM) and Fourier transform infrared
- spectroscopy (FTIR) were performed to characterize the gold nanoparticle decoration and to examine the thiol monolayer bonding to the MWCNTs. The detection of aromatic vapours using Au-MWCNT and HDT/Au-MWCNT sensors down to the ppm range shows that the presence of the self-assembled layer increases the
- -assembled monolayer of 1-hexadecanethiol (HDT). The sensor functionalisation was undertaken through its immersion for 4 hours at room temperature in a solution of 5 mM of HDT diluted in ethanol. The sensor was then rinsed with ethanol to wash off the unbound thiol molecules and dried under a nitrogen stream
Adsorption and desorption of self-assembled L-cysteine monolayers on nanoporous gold monitored by in situ resistometry
Beilstein J. Nanotechnol. 2019, 10, 2275–2279, doi:10.3762/bjnano.10.219
- using the well-known spontaneous formation of self-assembled monolayers (SAMs) on gold substrates [5]. These layers usually consist of three groups: a thiol as the head group, a carbon chain as the backbone and an end group that can be chosen according to the requirements for subsequent application. For
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