3-mercaptopropyl Trimethoxysilane Research Articles

Development and Comparison of Surface-Enhanced Raman Scattering Gold Substrates for In Situ Characterization of ‘Model’ Analytes in Organic and Aqueous Media

Surface-Enhanced Raman Spectroscopy (SERS) is a technique that provides high enhancement of Raman scattering from molecules adsorbed on a rough noble metal surface. The aim of this study was the development of convenient and reproducible in situ SERS methods suitable for the detection and the quantification of analytes in organic or aqueous media. For this purpose, we used a signal acquisition technique which simply consisted of recording the SERS signal in the bulk solution by using a Raman immersion probe close to the surface of the immersed solid SERS substrate. This method should be useful for on-line process analysis and more robust than conventional acquisition techniques that are generally based on a drying step which may induce heterogeneous analyte repartition onto the substrate surface, thus often requiring the use of SERS mapping technique to improve the signal reproducibility. In this study, two types of gold SERS substrates (metal nanostructures on a solid substrate and metal nanoparticles in suspension) were investigated and compared for the in situ characterization of two ‘model’ analytes, Rhodamine 6G (R6G) and 1,2-bis(4-pyridyl)ethylene (BPE), in aqueous and organic media. The solid substrate developed by sputtering deposition of a nanometric gold film onto a glass slide provided reproducible and stable SERS signals of BPE in organic media at concentration down to 10−12 M. But it appeared unusable in aqueous solutions due to the removal of the gold deposit. Despite an improvement of the deposit adhesion onto the substrate by using tetraethoxysilane/(3-mercaptopropyl) trimethoxysilane sol or the use of an electroless deposition technique, the developed solid substrates did not allow to reach satisfying R6G SERS signal in aqueous solutions. Therefore, both star-like and spherical gold nanoparticles were finally developed and used as SERS substrates. After aggregation, colloids induced the best enhancement of R6G Raman signal with a possible quantification at concentrations down to 5.10−9 M.

A simple synthesis route for preparation and optical properties of PMMA-g-ZnO nanocomposites through surface-initiated radical polymerization

An effortless chemisorption access for the planning of nanocomposites containing a semiconductor ZnO nanoparticles and poly(methyl methacrylate) (PMMA) is demonstrated. First, thiol-functionalized ZnO (ZnO-SH) were prepared by a silanization reaction between ZnO nanoparticles and (3-mercaptopropyl) trimethoxysilane. Then, a reserved radical polymerization of methyl methacrylate in the attendance of Zinc oxide-thiol (ZnO-SH) and butyrolactam produced PMMA-g-ZnO nanocomposites. DSC were used to examine the weight decline of glass transition temperature of nanocomposites. The ocular characteristics of the nanocomposites were studied by Ultraviolet-visible (UV–vis) absorption spectroscopy and photoluminescence spectroscopy (PL). The results accentuate the role of the grafted PMMA polymer segments in augmenting the strength of dispersal and near-band edge (NBE) emission of ZnO nanoparticles.

Nanocomposite system of simultaneously-thiolated graphene oxide and polyaniline nanofibers for energy storage applications

New electrode material was synthesized via in situ simultaneous-thiol-treatment (STT) of graphene oxide (GO) and polyaniline nanofibers (Pnf), using a small percent of (3-Mercaptopropyl) trimethoxysilane (MPT) as the thiol precursor, during the process of polymerization in high acidic environment. The measured XRD and FTIR spectra confirmed the enhancement of the Pnf binding without impairing its conjugation, and the reduction of GO via chemical modification of the hydroxyl and epoxide groups. The thiolated Pnf-GO system was also characterized by EDX, SEM and TEM, and the results showed a well dispersive porous structure as well as an increase in the surface area over the non-thiolated Pnf-GO system by a factor of 2. Electrochemical studies revealed a well-defined redox peak, suggesting high faradaic contribution. The results of the performed different electrochemical tests agreed on the improvement of the specific capacity and the reduction of the charge-transfer resistance, which were facilitated by the morphological structure of the thiolated Pnf-GO nanocomposite system. A modified Randles equivalent circuit succeeded to model the impedance spectrum of the new electrode system by adding a finite-length Warburg element to account for the highly porous nanoscale structure and the randomly aligned diffusion boundaries.

Facile synthesis of organosilica-capped mesoporous silica nanocarriers with selective redox-triggered drug release properties for safe tumor chemotherapy.

As drug-delivery carriers for cancer chemotherapy, gatekeeper-capped mesoporous silica nanoparticles (MSNs) have been widely studied due to their high drug-loading capability, controlled drug release property and good biocompatibility. However, the currently reported gatekeeper-capped MSNs suffer from complex synthetic procedures, potential toxicity of gatekeepers, unsatisfactory control on drug stimuli-release, etc. In this work, we develop a simple but efficient approach to fabricate PEGylated organosilica-capped mesoporous silica nanoparticles (POMSNs) by employing a disulfide-doped organosilica coating as the gatekeeper formed by the hydrolysis and condensation of a silane coupling agent 3-(mercaptopropyl)trimethoxysilane (MPTMS) to block the mesopores of MSNs. Owing to the glutathione (GSH)-responsive biodegradation behavior of the disulfide-doped organosilica gatekeeper, the DOX-loaded POMSNs exhibit only 20% cell viability towards SMMC-7721 tumor cells, and almost no toxicity towards L-02 cells at a DOX concentration of 50 μg mL-1 was measured, demonstrating their selective cytotoxicity in vitro. More importantly, it is demonstrated that the DOX-loaded POMSNs exhibit a tumor inhibition rate of 71.3% and negligible systematic toxicity. Consequently, the resultant POMSNs show great potential as drug nanocarriers for redox-responsive drug release and passive-targeting tumor chemotherapy.

Full-color-emitting (CuInS2)ZnS-alloyed core/shell quantum dots with trimethoxysilyl end-capped ligands soluble in an ionic liquid.

Zinc-copper-indium sulfide (ZCIS)-alloyed quantum dots are emerging as a new family of low toxic I–III–VI semiconductors due to their broad and color-tunable emissions as well as large Stokes shifts. Here, we fabricated a series of ZCIS QDs with tunable PL wavelengths and band-gap energies via a facile strategy by varying the ratio of A1–3 stock (Cu+/In3+) to the B stock (Zn2+) content. The ZnS shell was formed to improve the PL emission efficiency of the core nanoparticles and the PL emission wavelength of the resulting ZCIS/ZnS NCs gradually blue-shifted with an increase in the number of shell layers, resulting in a wide range of emissions from 800 nm to 518 nm that can be tuned by the core compositions or shell layer numbers for ZCIS/ZnS. Finally, the long-chain ligands dodecanethiol/octadecylamine on the quantum dots' surface were efficiently replaced by (3-mercaptopropyl)trimethoxysilane, thus enabling their solubility in an ionic liquid, which was confirmed via GC-MS. It also benefited for the co-dissolution of the polymers and chemical binding with other materials through the reactive silanol group, which provide stable and well-distributed ZCIS/ZnS QDs composites or surface coating by the QDs.

Effect of Etchant on SOI Wafer Surface Roughness for APTES Silanization

Abstract In biosensor, organic molecule is used as coupling agent for silicon wafer to attach with DNA since DNA cannot be directly bonded with the silicon surface. There are several organic molecules that can self-assemble on silicon surface and modify their properties. Silane molecules such as (3-aminopropyl) triethoxysilane (APTES), (3-(aminopropyl) triethoxysilane (APTMS) and (3-mercaptopropyl) trimethoxysilane (MPTMS) have been commonly used as a primary step to covalently attach on silicon-on-insulator (SOI) wafer. Silanes were attached to the Si-O-Si bond on the surface on SOI wafer. In this research, the effect of APTES silanization on the surface roughness of SOI wafer was studied. Tetramethylammonium hydroxide (TMAH) was used to etch SOI wafer. Ranges of surface roughness of SOI wafer were obtained after adding some additives such as isopropyl alcohol (IPA) and triton X-100. Subsequently, gold nanoparticles (AuNPs) were attached on SOI wafer surface to confirm the existing of APTES. The surface roughness of SOI wafer was characterized in detail using atomic force microscope (AFM) and scanning electron microscope (SEM). The wettability of APTES solution on the etched SOI wafer surface was measured using goniometer. It was found that lower surface roughness of SOI wafer was observed after etched using ternary solutions that consisted of TMAH, Triton X-100 and IPA. It produced excellent hydrophilic effect of APTES solution then resulted in the highest weight percent of gold attached on the SOI wafer after the silanization process.

Biodegradability of Disulfide-Organosilica Nanoparticles Evaluated by Soft X-ray Photoelectron Spectroscopy: Cancer Therapy Implications

Two kinds of organosilica nanoparticles (NPs) that were fabricated from thiol-containing precursors, (3-mercaptopropyl)trimethoxysilane (MPMS) and (3-mercaptopropyl)methyldimethoxysilane (MPDMS), a...

A Toolbox for the Synthesis of Multifunctionalized Mesoporous Silica Nanoparticles for Biomedical Applications.

Mesoporous silica nanoparticles (MSNs) are considered as promising next-generation nanocarriers for health-related applications. However, their effectiveness mostly relies on their efficient and surface-specific functionalization. In this contribution, we explored different strategies for the rational multistep synthesis of functional MCM-48-type MSNs with selectively created active inner and/or external surfaces. Functional groups were first installed using a combination of (delayed) co-condensation and post-grafting procedures. Both amine [(3-aminopropyl)triethoxysilane (APTS)] and thiol [(3-mercaptopropyl)trimethoxysilane (MPTS)] silanes were used, in various addition sequences. Following this, the different platforms were further functionalized with polyethylene glycol and/or with a pro-chelate ligand used as a magnetic resonance imaging contrast agent (diethylenetriaminepentaacetic acid chelates) and/or loaded with quercetin and/or grafted with an organic dye (rhodamine). The efficiency of the multiple grafting strategies and the effects on the MSN carrier properties are presented. Finally, the colloidal stability of the different systems was evaluated in physiological media, and preliminary tests were performed to verify their drug release capability. The use of MPTS appeared beneficial when compared to APTS in delayed co-condensation procedures to preserve both selective distribution of the functional groups, reactive functionality, and pore ordering. Our results provide in-depth insights into the efficient design of (multi)functional MSNs and especially on the crucial role played by the sequence of step-by-step functionalization methods aiming to produce multipurpose and stable bioplatforms.

Characterisation and investigation of antibacterial properties of nylon 66/TPS/Ag NPs nanofibre membranes

Electrospinning method was used to prepare nylon 66 nanofibre membranes in solution mixed with chloroform/formic acid. These nanofibres were covered with (3-mercaptopropyl) trimethoxysilane (TPS) that has a sulphur group, making it a suitable host for Ag nanoparticles (Ag NPs). Spraying of the as-prepared nylon 66/TPS surface first with silver nitrate solution and then scattering with a mixture of N2H4/NaBH4 used as reducing agents during the second process provides nanofibres with nylon 66/TPS/Ag NPs structure. Characterisation of the formed nanofibres was studied by Fourier transform infrared, scanning electron microscopy, X-ray diffraction and transmission electron microscopy techniques. The non-woven polyurethane coated with activated carbon particles and polyethylene mesh was utilised as the substrate and protective layers of as-prepared nanofibres, respectively. Finally, the antibacterial activity of nanofibre membranes against gram-positive and gram-negative bacteria was investigated by using the disk diffusion method and it was shown that the newly synthesised nanofibres presented very good antibacterial activity against the tested bacteria. The results of this study can be used for industrial applications such as antibacterial wound dressings or/and water disinfection filters.

Kajian Struktur dan Morfologi Grafin Oksida Bersulfonat yang Disediakan dengan Pelopor Berbeza

In this study, graphene oxide (GO) as nano sized filler to improve the properties of polymer electrolyte membrane was synthesized via the modified Hummers method. Hummers is the most common method used to synthesize GO. The GO is produced by exfoliation of graphite oxide under sonication method. Dispersion by sonication method shows mechanical disruption that breaks apart the graphite flakes which is then sterically stabilized in the base solution. The as-synthesized GO will be sulfonated using different precursors, namely (3-mercaptopropyl)trimethoxysilane (MPTMS), butane sultone (BS) and sulfanilic acid (SA). The structure and morphology of GO and sulfonated GO (SGO) were investigated in details by using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). FTIR analysis confirmed the presence of several functional groups such as hydroxyl, epoxy, carbonyl, carboxyl and sulfonic acid group. The obtained SEM and TEM images indicated, that the morphology of GO dispersion is folded, multilayered and crumpled with some wrinkles. The morphology of SGO showed a folded, thicker and overlap surface compared with GO sheets. Based on TEM image, the addition of sulfonic acid group into the GO network reveals the black spot on the sheets surface. This SGO will act as a potential base material for the application of solid acid catalyst, water purification as well as a composite in membrane fabrication.

High-toughness PLA/Bamboo cellulose nanowhiskers bionanocomposite strengthened with silylated ultrafine bamboo-char

We prepared poly(lactic acid) (PLA)/bamboo cellulose nanowhiskers (BCNW) bionanocomposite with a high toughness but a low modulus in the previous work. In this paper, a new reinforcement, silane surface-modified ultrafine bamboo-char (UFBC), was employed to strengthen the binary PLA/BCNW bionanocomposite. The ternary bionanocomposite films were fabricated by a solution casting with different contents of surface-treated UFBC in the range of 0.25 wt% to 4.0 wt%. The functionalization of UFBC with (3-mercaptopropyl)trimethoxysilane (A-189) favored its dispersion in the PLA matrix; sea-island and nuclear-shell characteristics were observed by the scanning electron microscopy (SEM) and transmission electron microscopy (TEM). When the UFBC content was 0.25 wt%, the tensile strength and elongation at break increased by 99.26% and 104.93%, respectively, comparing to the neat PLA. Differential scanning calorimetry (DSC) results showed that glass transition temperature, crystallization temperature, crystallization enthalpy and crystallinity increased with the increase of UFBC contents. Thermogravimetric analysis demonstrated that the thermal degradation stability decreased with the UFBC addition. BCNW and UFBC produced a synergistic effect on composites’ toughening and strengthening. These results provided a basic understanding of PLA enhancement mechanism and a simple approach for PLA composite manufacture with sound mechanical properties.

Ultrahigh Conductivity and Superior Interfacial Adhesion of a Nanostructured, Photonic-Sintered Copper Membrane for Printed Flexible Hybrid Electronics.

Inkjet-printed electronics using metal particles typically lack electrical conductivity and interfacial adhesion with an underlying substrate. To address the inherent issues of printed materials, this Research Article introduces advanced materials and processing methodologies. Enhanced adhesion of the inkjet-printed copper (Cu) on a flexible polyimide film is achieved by using a new surface modification technique, a nanostructured self-assembled monolayer (SAM) of (3-mercaptopropyl)trimethoxysilane. A standardized adhesion test reveals the superior adhesion strength (1192.27 N/m) of printed Cu on the polymer film, while maintaining extreme mechanical flexibility proven by 100 000 bending cycles. In addition to the increased adhesion, the nanostructured SAM treatment on printed Cu prevents formation of native oxide layers. The combination of the newly synthesized Cu ink and associated sintering technique with an intense pulsed ultraviolet and visible light absorption enables ultrahigh conductivity of printed Cu (2.3 × 10-6 Ω·cm), which is the highest electrical conductivity reported to date. The comprehensive materials engineering technologies offer highly reliable printing of Cu patterns for immediate use in wearable flexible hybrid electronics. In vivo demonstration of printed, skin-conformal Cu electrodes indicates a very low skin-electrode impedance (<50 kΩ) without a conductive gel and successfully measures three types of biopotentials, including electrocardiograms, electromyograms, and electrooculograms.

Synthesis of solid acid catalysts for esterification with the assistance of elevated pressure

Abstract Acidic catalysts dedicated for esterification processes were prepared by immobilization of (3-mercaptopropyl)trimethoxysilane (MPTMS) on mesoporous silica and niobiosilicate material using a new methodology, i.e. solvothermal technique with increased pressure. The structure and surface properties of the samples obtained were examined using N2 adsorption/desorption, XRD, TEM, XPS and elemental analysis. The impact of modification technique as well as the presence of niobium in the sample on the acidity of final materials was investigated. It was found that the application of external pressure during the solvothermal modification of mesoporous silica with MPTMS allows obtaining materials with a greater number of acidic sites. These samples showed a high activity and stability in esterification of acetic and propionic acid with n-butanol and n-hexanol.

Effect of in situ silanization of multiwalled carbon nanotubes on the properties of NBR/MWCNT-OH composites

ABSTRACTThis paper presents the preparation and properties of improved acrylonitrile-butadiene rubber (NBR) composites with hydroxylated carbon nanotubes (MWCNT-OH). A series of in situ modifications were performed using [3-(2-aminoethylamino)propyl]trimethoxysilane (APTS), vinyltrimethoxysilane (VTS) and (3-mercaptopropyl)trimethoxysilane (MPTS). The curing behavior, crosslink density, static and dynamic mechanical properties (DMTA), filler-filler interactions (Payne effect), thermal stability (TGA) and aging stability of the NBR nanocomposites were investigated, in addition to morphological studies (SEM/EDS). The experimental data prove that the most promising silane agent stongly affecting the properties of NBR/MWCNT-OH composite systems was APTS. The NBR vulcanizates showed increased torque, crosslink density, dynamic moduli and tensile strength.

Removal of Pb(II), Cd(II) and Hg(II) from aqueous solution by mercapto-modified coal gangue

A low-cost mercapto-modified coal gangue (CG-SH) was fabricated by modification of coal gangue (CG) with (3-mercaptopropyl) trimethoxysilane. The structure and composition for as-prepared CG-SH were characterized by using X-ray diffraction (XRD), Fourier transfer infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray fluorescence (XRF). Results indicated that larger amounts of mercapto-groups (-SH) was successfully introduced onto CG, which followed by acted as active sites for the removal of heavy metal cations, such as Pb(II), Cd(II) and Hg(II). The factors that affected the adsorption equilibrium as well as the removal efficiency, i.e., contact time, initial concentration, pH and temperature, were investigated in detail. The adsorption isotherms for Pb(II), Cd(II) and Hg(II) were well fitted with Langmuir model. The maximum adsorption capacity of CG-SH for Pb(II), Cd(II) and Hg(II) were calculated to be 332.8, 110.4 and 179.2 mg g−1, respectively. The adsorption for Pb(II), Cd(II) and Hg(II) on CG-SH could be well described by pseudo-second-order kinetic model. And thermodynamic analysis suggests that the adsorption process for Pb(II) is exothermal, while that for Cd(II) and Hg(II) are endothermal. The results suggest CG-SH have great potential to be used as efficient absorbent for the removal of heavy metal cations from water.

Surface Modification of Wool Fabric with POSS® Nanomaterial

Wool fabrics, without any surface treatment, can undergo undesirable and irreversible structural changes of wool fiber during washing under heat and mechanical agitation, leading to high shrinkage of wool garments. The traditional method based on polyamide resin can prevent felting and/or shrinkage of wool textiles, but adversely affect the surface hydrophobicity. In the present study, a treatment solution was developed based on TriSilanolIsooctyl POSS® and 3- mercaptopropyl trimethoxysilane, which created wool surface with increased hydrophobicity and highly resistant to shrinkage or felting, as measured after 3×5A wash cycles (equivalent to 24 domestic washes). After the treatment, the wool fabric appeared to be superhydrophobic with a water contact angle of above 150°, compared to the untreated fabric. The treatment has marginal effect on mechanical performance as observed in tensile properties. Scanning electron microscopic images revealed a coating of POSS® on the wool surface. The dyeing of untreated and treated fabrics appeared to be uniform to the naked eye, though spectrophotometric analysis indicated a difference in the extent of dyeing performance. This research showed that POSS®-based treatment is a potentially effective approach for developing shrink-resistant wool textiles with enhanced surface hydrophobicity, in contrast to traditional chlorine/polyamide resin treatment.

Synthesis of tetra-substituted phenanthroimidazole derivatives using SBA-Pr-SO3H

A one pot four-component reaction of 9,10-phenanthraquinone, aromatic aldehyde, aniline, and ammonium acetate was designed for the preparation of tetrasubstituted imidazoles (phenanthro[9,10-d]imidazole) derivatives in the presence of SBA-Pr-SO3H as a mesoporous solid acid catalyst. Phenanthro[9,10-d]imidazole derivatives were produced by the use of this technique in short reaction times and good to high yields. SBA-15 (Santa Barbara Amorphous), as a hexagonal mesoporous silica with 6 nm pore diameter, was synthesized and then its internal surface was modified with (3-mercaptopropyl)trimethoxysilane following an oxidation process to gain SBA-Pr-SO3H. The latter was then characterized; SEM image showed uniform particles about 700-900 nm and TEM image demonstrated the presence of parallel channels, which resemble the pores configuration of SBA-15. Additionally, the weight reduction in TGA curve in the temperature range of 200-600 °C (about 20% mass loss) established that the anchored propyl sulfonic acid groups onto the SBA-15 pores is about 1.2 mmol/g. This data was also confirmed by back-titration of SBA-Pr-SO3H with standardized NaOH and HCl solutions.

MoS2 Quantum Dot/Graphene Hybrids for Advanced Interface Engineering of a CH3NH3PbI3 Perovskite Solar Cell with an Efficiency of over 20.

Interface engineering of organic-inorganic halide perovskite solar cells (PSCs) plays a pivotal role in achieving high power conversion efficiency (PCE). In fact, the perovskite photoactive layer needs to work synergistically with the other functional components of the cell, such as charge transporting/active buffer layers and electrodes. In this context, graphene and related two-dimensional materials (GRMs) are promising candidates to tune "on demand" the interface properties of PSCs. In this work, we fully exploit the potential of GRMs by controlling the optoelectronic properties of molybdenum disulfide (MoS2) and reduced graphene oxide (RGO) hybrids both as hole transport layer (HTL) and active buffer layer (ABL) in mesoscopic methylammonium lead iodide (CH3NH3PbI3) perovskite (MAPbI3)-based PSCs. We show that zero-dimensional MoS2 quantum dots (MoS2 QDs), derived by liquid phase exfoliated MoS2 flakes, provide both hole-extraction and electron-blocking properties. In fact, on one hand, intrinsic n-type doping-induced intraband gap states effectively extract the holes through an electron injection mechanism. On the other hand, quantum confinement effects increase the optical band gap of MoS2 (from 1.4 eV for the flakes to >3.2 eV for QDs), raising the minimum energy of its conduction band (from -4.3 eV for the flakes to -2.2 eV for QDs) above the one of the conduction band of MAPbI3 (between -3.7 and -4 eV) and hindering electron collection. The van der Waals hybridization of MoS2 QDs with functionalized reduced graphene oxide (f-RGO), obtained by chemical silanization-induced linkage between RGO and (3-mercaptopropyl)trimethoxysilane, is effective to homogenize the deposition of HTLs or ABLs onto the perovskite film, since the two-dimensional nature of RGO effectively plugs the pinholes of the MoS2 QD films. Our "graphene interface engineering" (GIE) strategy based on van der Waals MoS2 QD/graphene hybrids enables MAPbI3-based PSCs to achieve a PCE up to 20.12% (average PCE of 18.8%). The possibility to combine quantum and chemical effects into GIE, coupled with the recent success of graphene and GRMs as interfacial layer, represents a promising approach for the development of next-generation PSCs.

Magnetism-Resolved Separation and Fluorescence Quantification for Near-Simultaneous Detection of Multiple Pathogens.

In the modern era of molecular evidence-based medicine and advanced biomedical technologies, the rapid, sensitive and specific assay of multiple pathogens is critical to, but largely absent from, clinical practice. Therefore, to improve the current ordinary separation and collection method, we report herein a strategy of magnetism-resolved separation and fluorescence quantification for near-simultaneous detection of multiple pathogens, followed by the direct antimicrobial susceptibility testing (AST). To accomplish this strategy, we utilized aptamer-modified fluorescent-magnetic multifunctional nanoprobes (apt-FMNPs). FMNPs with intriguing different magnetic responses and excellent fluorescence quality were first self-assembled based on metal coordination interaction using (3-mercaptopropyl) trimethoxysilane, magnetic γ-Fe2O3, and fluorescent quantum dots as matrix components. Then, aptamers, which specific to target pathogens of Escherichia coli O157:H7 ( E. coli) and Salmonella typhimurium ( S. typ), were conjugated with FMNPs to yield apt-FMNPs nanoprobes for multiple pathogens assay. Based on the discrepant magnetic response of pathogen@nanoprobes complex under the identical external magnetic field, the model bacteria were fished out by magnetic adsorption at different time points and subjected to fluorescence quantification with good linear ranges and detection limits within 1h. Multiple pathogens spiked in real samples were also effectively detected by the apt-FMNPs and sequentially fished out for AST assay, which showed similar results to that for pure pathogens. The apt-FMNPs-based strategy of near-simultaneous detection of multiple pathogens shows promise for the potential application in the diagnosis and treatment of pathogen-related infectious diseases.

Organosilicon compounds with various active groups as consolidants for the preservation of waterlogged archaeological wood

Abstract Waterlogged wood conservation focuses primarily on its dimensional stabilisation to prevent irreversible deformations that occur upon drying. It also aims to solve the concerns regarding wood degradation as well as its physico-mechanical properties, all of which are inextricably connected with wood hygroscopicity. Therefore, the reduction of wood hygroscopicity can provide a solution to some of the conservation problems. Due to the hydrophobising properties and the ability to cell wall bulking, a set of organosilicons with various active groups were selected to evaluate their stabilisation effect on highly degraded medieval waterlogged elm wood. Exceptionally satisfying results were obtained for (3-Mercaptopropyl)trimethoxysilane, 1,3-Bis(diethylamino)-3-propoxypropanol)-1,1,3,3-tetramethyldisiloxane and Methyltrimethoxysilane, for which the volumetric anti-shrink efficiency was around 98%, 90% and 81%, respectively. Additionally, the applied treatment resulted in a decrease of wood moisture content from 6.7% for untreated wood to 2.4–3.6% for wood treated with the above-mentioned compounds. Neither the alkoxysilanes with a long alkyl chain, nor those terminated with a highly hydrophilic pyridine ring were found effective for waterlogged wood stabilisation. It can be concluded that the organosilicon compounds with alkoxy groups and a relatively short alkyl chain or containing and additional chemical group enable to form stable bonds with wood components proved to be the most effective wood stabilisers.