3-aminopropyl Trimethoxysilane Research Articles

Polyoxometalate/Cellulose Nanofibrils Aerogels for Highly Efficient Oxidative Desulfurization.

Polyoxometalate (POM) presents great potential in oxidative desulfurization (ODS) reaction. However, the high dissolubility of POM in common solvents makes it difficult to recycle. Besides, the small specific surface area of POM also limits the interaction between them and the substrate. Depositing polyoxometalates onto three-dimensional (3D) network structured materials could largely expand the application of POM. Here, the surfaces of cellulose nanofibrils (CNFs) were modified with very few (3-Aminopropyl) trimethoxysilane (APTS) to endow positive charges on the surfaces of CNFs, and then phosphotungstic acid (PTA) was loaded to obtain the aerogel A-CNF/PTA as the ODS catalyst. FT-IR indicated the successful deposition of PTA onto aminosilane modified CNF surfaces. UV-VIS further suggested the stability of PTA in the aerogels. BET and SEM results suggested the increased specific surface area and the relatively uniform 3D network structure of the prepared aerogels. TGA analysis indicated that the thermal stability of the aerogel A-CNF/PTA50% was a little higher than that of the pure CNF aerogel. Most importantly, the aerogel A-CNF/PTA50% showed good catalytic performance for ODS. Catalysis results showed that the substrate conversion rate of the aerogel A-CNF/PTA50% reached 100% within 120 min at room temperature. Even after five cycles, the substrate conversion rate of the aerogel A-CNF/PTA50% still reached 91.2% during the dynamic catalytic process. This work provides a scalable and facile way to stably deposit POM onto 3D structured materials.

Magnetic solid-phase extraction of norfloxacin by core-shell magnetic nanoparticles

Two magnetic metal-organic frameworks were synthesized with a core-shell structure. Maghemite (γ-Fe2O3) as the magnetic core was used to prepare γ-Fe2O3@SiO2, γ-Fe2O3@SiO2-NH2 and γ-Fe2O3@SiO2-NH2-COOH nanoparticles (MNPs) via tetraethyl orthosilicate (TEOS), (3-aminopropyl)trimethoxysilane (APTMS) and glutaric anhydride (GA). γ-Fe2O3@SiO2-NH2-COOH nanoparticles were further modified by Core-Shell package of Tb-BDC-NH2 and Tb-BDC, in which the ligands were 2-aminoterephthalic acid (H2BDC-NH2) and terephthalic acid (H2BDC). IR spectra were used for structure determination of γ-Fe2O3, γ-Fe2O3@SiO2, γ-Fe2O3@SiO2-NH2-COOH and γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC nanoparticles. Magnetic solid-phase extraction (MSPE) of norfloxacin (Nor) experiments exhibited that, for γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC-NH2 nanoparticles, the best adsorption was obtained at pH = 6. For γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC nanoparticles, the best adsorption was obtained at pH = 4. γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC nanoparticles exhibit characteristic TbIII emission spectra at 490 (5D4→7F6), 545 (5D4→7F5), 585 (5D4→7F4) and 621 nm (5D4→7F3) after MSPE of norfloxacin. X-ray photoelectron spectroscopy (XPS) spectra are used for determination of γ-Fe2O3@SiO2-NH2-COOH, γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC and γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC + Nor nanoparticles. XPS results showed that coordination occurs between γ-Fe2O3@SiO2-NH2-COOH/Tb-BDC nanoparticles and Nor.

Preparation and Tribological Behaviors of Modified Rice Husk Carbon/MoS2 Composite Particles as a Functional Additive in Polyethylene Glycol

Rice husk carbon/molybdenum disulfide (RHC/MoS2) nanoparticles were prepared by a chemical precipitation method in order to comprehensively utilize the rice husk. 3-Aminopropyl trimethoxysilane (ATS) was used as a surface modifier to promote the dispersion capability of RHC/MoS2 particles in polyethylene glycol. The tribological behavior of polyethylene glycol (PEG) with different amount of modified particles was investigated using a ball-disk tribometer at the different velocities and loads. A three-dimensional (3D) laser scanning microscope (LSM) and x-ray photoelectron spectroscopy (XPS) were used to clarify the friction and wear mechanisms of modified composite particles in PEG. Results show that the modified RHC/MoS2 has good friction characteristics and dispersion in PEG. Modified RHC/MoS2 particles can effectively improve the wear resistance and friction reduction properties of PEG. The optimal additions of two kinds of particles are both 0.5 wt%. Friction and wear mechanism of composite particles were ascribed to the tribofilm that came from the components of composite particles.

Modeling the catalytic conversion of anthracene oil fraction to light aromatics over mesoporous HZSM-5

Silanization of zeolite units has been proved to be an effective way to improve the hierarchical porosity of HZSM-5. Mesoporous HZSM-5 (YJGW-X: X = 0, 5, 10) were synthesized by adopting phenyl amino propyl trimethoxy silane (YJGW) with different addition (0 wt%, 5 wt% and 10 wt%), followed were applied to investigating the interaction between the compounds of various categories during the conversion process of anthracene oil fraction of low temperature coal tar. Model compounds (MCs), which including naphthol (Nap-ol), methyl naphthalene (Nap-met), methyl anthracene (Ant-met) and C22 alkanes (C22), are selected as raw materials to investigate the conversion progress of anthracene oil fraction of low temperature coal tar using Py-GC/MS. Results show that YJGW addition has a significant role on the acidity and pore size. Besides, the higher aromatic selectivity exhibited by YJGW-5 and YJGW-10 compared to YJGW-0 in the catalytic pyrolysis of single MCs indicates that the addition of YJGW does facilitate the hydrocracking of polycyclic aromatics hydrocarbons to prepare small reactive molecules. When mixed MCs pyrolyzed using YJGW-X, the experimental yield of BTEXN (benzene, toluene, ethyl-benzene, xylene and naphthalene) is higher than theoretical one. When pyrolyzed at 450 °C, the highest experimental yield (2578.35 mg/kg) of BTEXN is obtained using YJGW-10, owing to its appropriate pore structure and acidity. Moreover, the possible formation mechanism of BTEXN derived from MCs catalytic pyrolysis was proposed on the basis of structural features and catalytic performances of YJGW-X.

Pickering emulsions for the polymerization of ε-caprolactone in continuous flow process

Using the potential of compartmenting free enzyme in dispersion phase of Pickering emulsion, a simple continuous flow system for free enzyme catalytic cycle-opening polymerization of ε-caprolactone has been studied. In order to generate suitable and stable Pickering emulsions, silica nanoparticles(SiNPs) modified with octyltrimethoxysilane (OTMS) and aminopropyltrimethoxysilane (APTMS) are synthesized, and the modification is confirmed by Fourier transformed infrared (FTIR) spectroscopy and water contact angle (CA). It is found that CA values of modified SiNPs increased from 107° to 168° with the increase of ratio of OTMS to APTMS from 1:1 to 8:1, which indicates that wettability of SiNPs has been changed from original hydrophilic to hydrophobic and consequent has an effect on the properties of Pickering emulsions. Among the modified SiNPs, the silica modified with OTMS: APTM (2:1) can construct stable W(water)/O(toluene) Pickering emulsion, confirmed by images from confocal laser microscope. The stable Pickering emulsion comprising of Candida Antarctica lipase B dispersed in water droplets is selected as a model for investigation of conditions for ring-opening polymerization of ε-caprolactone. The high monomer conversion is achieved with amount of emulsifier and enzyme being used 5 wt% and 3 wt%, respectively, and flow rate 3 mL h−1in continuous flow process, which is higher than that in batch reaction system although the formula of Pickering emulsion is identical. Specially, the polycaprolactone (PCL) with an average molecular weight of 210151 g/mol, as per gel permeation chromatography (GPC) analysis, is achieved. The catalytic efficiency of enzyme for polymerization is not changed even after several cycles of use. The present enzyme immobilization within Pickering emulsion offers a green and prospective approach for synthesis of high molecular weight polymer in continuous flow process.

Nitrogen-rich silicon quantum dots: facile synthesis and application as a fluorescent 'on-off-on' probe for sensitive detection of Hg2+ and cyanide ions.

The sensitive and reliable detection of Hg2+ and CN- as harsh environmental contaminants are of great importance. In view of this, a novel 'on-off-on' fluorescent probe based on nitrogen-rich silicon quantum dots (NR-SiQDs) has been designed for sensitive detection of Hg2+ and CN- ions in aqueous medium. NR-SiQDs were synthesized using a facile, one-step, and environment friendly procedure in the presence of 3-aminopropyl trimethoxysilane (APTMS) and ascorbic acid (AA) as precursors, with l-asparagine as a nitrogen source for surface modification. The NR-SiQDs exhibited strong fluorescence emission at 450 nm with 42.34% quantum yield, satisfactory salt tolerance, and superior photostability and pH stability. The fluorescence emission was effectively quenched using Hg2+ (turn-off) due to the formation of a nonfluorescent stable NR-SiQDs/Hg2+ complex, whereas after the addition of cyanide ions (CN- ), Hg2+ ions could be leached from the surface of the NR-SiQDs and the fluorescence emission intensity of the quenched NR-SiQDs fully recovered (turn-on) due to the formation of highly stable [Hg(CN)4 ]2- species. After optimizing the response conditions, the obtained limits of detection were found to be 53 nM and 0.46 μM for Hg2+ and CN- , respectively. Finally, the NR-SiQD-based fluorescence probe was utilized to detect Hg2+ and CN- ions in water samples and satisfactory results were obtained, suggesting its potential application for environmental monitoring.

The Preparation and Properties of Composite Hydrogels Based on Gelatin and (3-Aminopropyl) Trimethoxysilane Grafted Cellulose Nanocrystals Covalently Linked with Microbial Transglutaminase.

Mechanically enhanced gelatin-based composite hydrogels were developed in the presence of functionalized cellulose nanocrystals (CNCs) employing microbial transglutaminase (mTG) as a binding agent. In this work, the surfaces of CNCs were grafted with (3-Aminopropyl) trimethoxysilane with a NH2 functional group, and the success of CNCs’ modification was verified by FTIR spectroscopy and XPS. The higher degree of modification in CNCs resulted in more covalent cross-linking and dispersibility within the gelatin matrix; thus, the as-prepared hydrogels showed significantly improved mechanical properties and thermo-stability, as revealed by dynamic rheological analysis, uniaxial compression tests and SEM. The biocompatibility of the obtained hydrogels was evaluated by the MTT method, and it was found that the grafted CNCs had no obvious inhibitory effect on cell proliferation. Hence, the mechanically enhanced gelatin-based hydrogels might have great potential in biomedical applications.

Effect of graphene oxide wrapped functional silicon carbide on structural, surface protection, water repellent, and mechanical properties of epoxy matrix for automotive structural components

This study is aimed to develop novel nanocomposites with enhanced structural, mechanical and electrochemical properties for automotive applications. Polymeric coatings have been widely used in the automobile industry for the corrosion protection of metallic materials. The (3-aminopropyl)trimethoxysilane (APTMS) functionalized SiC was encapsulated by graphene oxide (GO) as an effective nanofiller in the epoxy matrix (EP). The protective performance of epoxy coating on mild steel in the presence of different concentrations of graphene oxide wrapped silicon carbide nanoparticles was evaluated in seawater by electrochemical impedance spectroscopy (EIS) and scanning electrochemical microscopy (SECM). The optimum percentage of graphene oxide embedded SiC nanoparticles in the epoxy matrix was found to be 2.0 wt% in which the coating has the least agglomeration and appropriate corrosion resistance. The EIS measurements showed an enhanced coating resistance of EP-GO/APTMS-SiC nanocomposite (6498.17 kΏ.cm2) after 720 h immersion in seawater compared to EP-SiC (1124.95 kΏ.cm2) and plain epoxy (1.21 kΏ.cm2) coatings. It was found that the coating resistance of the EP-GO/APTMS-SiC nanocomposite coating was around 31% higher than that of the EP matrix. SECM measurements confirmed that the least dissipation of ferrous ions were observed at the crack of the EP-GO/APTMS-SiC nanocomposite coated steel specimen (1.6 I/nA) due to the improved resistance for anodic dissipation of the coated substrate. FE-SEM/EDX examined that Si was reinforced in the degradation products which formed an excellent passive layer at the coating/steel interface. The results showed that the newly developed EP-GO/APTMS-SiC nanocomposite coating possessed superior corrosion protection and enhanced hydrophobic behaviors (WCA: 131º). Therefore, it was concluded that the EP-GO/APTMS-SiC coatings on mild steel displayed superior surface protection, water repellent, and mechanical behaviors in the marine environment for long periods of exposure. Thus, EP-GO/APTMS-SiC coatings on mild steel can be used in industrial and marine applications.

Poly(lactic acid) and polybutylene succinate films incorporated with modified zeolite

This research is focused on the development of film packagings for ripening fruits. Treated zeolite using (3-aminopropyl) trimethoxysilane as coupling agent was added in polybutylene succinate (PBS) and polylactic acid (PLA) blend of the ratio of 60:40. The effect of cation exchanged zeolite with K+, Rb+ and Fe3+ and loading of 1.25, 2.50 and 3.75 wt% zeolite was investigated on the properties of PBS/PLA/doped-zeolite composites. Mechanical properties of PBS/PLA/doped-zeolite composites films were tended to decrease when compared with PBS/PLA/undoped-zeolite films. Moreover, cation exchanged zeolite remains acting as the nucleating agent and would likely improve thermal stability of PBS/PLA/zeolite composites. The permeability of oxygen, carbon dioxide as well as water vapor permeation of PBS/PLA composites with the following cation exchanged zeolite films could be sorted in ascending order: Fe3+ < K+< Rb+, respectively. PBS/PLA/doped zeolite with K+ and Rb+ film packagings showed the extension capability of the ripening period for the subjected fruits by having a longer period than those of the PBS/PLA/zeolite/Fe3+ film packaging.

Study of the Fabrication Technology of Hybrid Microfluidic Biochips for Label-Free Detection of Proteins.

A study of the peculiarities and a comparative analysis of the technologies used for the fabrication of elements of novel hybrid microfluidic biochips for express biomedical analysis have been carried out. The biochips were designed with an incorporated microfluidic system, which enabled an accumulation of the target compounds in a biological fluid to be achieved, thus increasing the biochip system’s sensitivity and even implementing a label-free design of the detection unit. The multilevel process of manufacturing a microfluidic system of a given topology for label-free fluorometric detection of protein structures is presented. The technological process included the chemical modification of the working surface of glass substrates by silanization using (3-aminopropyl) trimethoxysilane (APTMS), formation of the microchannels, for which SU-8 technologies and a last generation dry film photoresist were studied and compared. The solid-state phosphor layers were deposited using three methods: drop application; airbrushing; and mechanical spraying onto the adhesive surface. The processes of sealing the system, installing input ports, and packaging using micro-assembly technologies are described. The technological process has been optimized and the biochip was implemented and tested. The presented system can be used to design novel high-performance diagnostic tools that implement the function of express detection of protein markers of diseases and create low-power multimodal, highly intelligent portable analytical decision-making systems in medicine.

Surface co-silanization engineering to enhance amine functionality for adhesive heterojunction and antimicrobial application

Surface functionalization of quartz is of practical importance for versatile applications. Amine functionality is constructed on quartz via surface composite engineering with an amine-terminated organosilane, 3-aminopropyl trimethoxysilane (APTMS). In this study, we demonstrate a facile co-silanization method which bulky triphenylsilanol (TPS) is introduced to spatially confine the grafting orientation of functional APTMS, giving rise to a well-organized APTMS-TPS composite nanolayer to maximize amine functionality and suppress molecular agglomeration. Contact angle measurement, atomic force microscopy, angle-resolved X-ray photoelectron spectroscopy, Kelvin probe force microscopy, ultraviolet photoelectron spectroscopy, and energy minimization calculation are used to identify the well-organized conformations of surface co-silanization. The co-silanized APTMS-TPS composite nanolayer exhibits high efficacy in the metal immobilization, acting as an adhesion promoter to increase the adhesion strength of Ni/quartz heterojunction. Immobilization of Ag nanoparticles on amine-functionalized quartz is also achieved which is a facile method to prepare an efficient antimicrobial surface.

Layer-by-layer assembly of nanofilms from colloidally stable amine-functionalized silica nanoparticles

The assembly of uniform thin films with functional silica nanoparticles (FSNPs) by the layer-by-layer (LbL) technique has been studied to provide rough, robust, and functional surfaces. Initially, monodisperse silica nanoparticles (SNPs) have been synthesized by the reverse microemulsion method. Then SNPs have been functionalized using amino silane coupling agents with various chain lengths and amine positions such as (3-aminopropyl)trimethoxy silane (APS), N-[3-(trimethoxysilyl)propyl]-N,N,N-trimethylammonium chloride (NPC), N -(6-aminohexyl)aminopropyltrimethoxy silane (AHAPS), and 3-aminopropyl(dimethyl)ethoxy silane (APDMES). The amine-functionalized silica nanoparticles have been characterized using zeta potential, Fourier Transform-Infrared Spectroscopy (FT-IR), and 1 H Nuclear Magnetic Resonance (NMR) spectroscopy to prove the existence of amine groups on the silica surface. Scanning electron microscopy (SEM) images have revealed that the LbL assembled thin film coatings of FSNPs are uniform and monodisperse. The thickness measurements of the coatings have been conducted by spectroscopic ellipsometry. Water contact angle measurements were performed to analyze the alteration of surface features with functional groups. The roughness, topography, and elastic modulus of the assembled thin-film coatings were probed by atomic force microscopy (AFM). The dispersion of AHAPS-FSNPs has indicated superior colloidal stability than other FSNPs because of their secondary amines creating steric hindrance. Moreover, AHAPS-FSNPs film exhibited the lowest coating thickness and the highest elastic modulus comparing with the other FSNPS because of their crosslinking and hydrogen-bonding ability. Briefly, in this work, LbL assembly of the amine FSNPs was established by an extensive investigation to form rough and functional surfaces for many demanding applications.

Controlled Growth of Organosilane Micropatterns on Hydrophilic and Hydrophobic Surfaces Templated by Vacuum Ultraviolet Photolithography.

In this report, micropatterns of (3-aminopropyl)trimethoxysilane (APTMS) were developed on hydrophilic and hydrophobic surfaces after patterning using 172 nm vacuum ultraviolet (VUV) photolithography. Self-assembled monolayers (SAMs) formed on Si substrates through UV hydrosilylation of 1-hexadecene (HD) and 10-undecenoic acid (UDA) were used as hydrophilic and hydrophobic surfaces, respectively. For templating the HD- and UDA-SAMs, the VUV light was exposed to HD- and UDA-SAMs from the slits of photomasks in atmospheric and evacuated environments, respectively. Various oxygenated groups were generated at the exposed domains of HD-SAM, while the COOH groups were trimmed from the irradiated domains of UDA-SAM. The APTMS molecules were immobilized on the domains that were terminated by oxygenated groups after chemical vapor deposition (CVD). The thicknesses of the developed APTMS micropatterns increased significantly by raising the CVD temperature and in the presence of ambient air in the CVD Teflon container as well. The increase in thicknesses was ascribed to the formation of APTMS multilayers, which were mediated by H3N+ ions. Also, the developed APTMS micropatterns on the UDA-SAM patterned by VUV light irradiation in a high-vacuum environment (HV-VUV) were thicker than those on the VUV/(O) patterned HD-SAM due to the presence of inactive oxygenated groups at the surface of VUV/(O)-terminated domains of HD-SAM such as COO-C and C-O-C groups. The presence of water or ambient air facilitated the silane coupling between the silyl groups with the oxygenated and amino groups The combination of VUV photolithography and the CVD method with control of the conditions would enable us to control the thicknesses and shapes of the developed APTMS micropatterns. These findings illustrate the applicability of VUV photolithography for templating hydrophobic and hydrophobic surfaces toward the development of organosilane architectures, which can be feasible for several applications.

Cinnamic acid-functionalized ZnO nanoparticles for constructing UV-shielding and mechanically robust polyvinyl butyral composites

Biomolecule cinnamic acid (CNA) was chemically grafted on the surface of ZnO nanoparticles (ZnO Nps) via (3-Aminopropyl) trimethoxysilane (KH550) as the linkage to obtain a novel UV-shielding material CNA-mZnO. It was found that CNA-mZnO exhibits stronger UV absorption property than pure ZnO. Moreover, CNA-mZnO could be homogeneously dispersed in polyvinyl butyral (PVB) matrix. As expected, the introduction of CNA-mZnO gives a positive effect on the UV-shielding performance and mechanical properties of PVB matrix. Particularly, the PVB with 2 wt% CNA-mZnO achieved a dramatically improved UV-shielding performance with UV-shielding efficiency more than 99% below 370 nm, along with satisfactory visible transmittance. Meanwhile, the maximum tensile strength of PVB/CNA-mZnO composite were approximately 50% enhancement than pure PVB. More importantly, the PVB/CNA-mZnO composites also possess the excellent anti-UV aging performance and exhibit high retention of mechanical properties after UV exposure for 96 h. This work proposed a new strategy to prepare UV-shielding and mechanically robust composites by introducing natural biomolecule-functionalized ZnO Nps, which may greatly promote their applications in packing, intelligent windows and optical devices.

Development of nanocellulose-titanium dioxide-(3-aminopropyl) trimethoxysilane (NCC-TiO2-APTMS) particles and their application in superhydrophilic self-cleaning coatings

Development of nanocellulose-titanium dioxide-(3-aminopropyl) trimethoxysilane (NCC-TiO2-APTMS) particles and their application in superhydrophilic self-cleaning coatings

A simple and highly reliable method to enhance the adhesion properties of polyethylene using Kapton-taping process

Although polyethylene (PE) is one of the most frequently used synthetic polymers in the plastics market, it is very difficult to imprint or bond PE with adhesives without pre-treatments based upon electrical, chemical and thermal processes. This is because a uniform adhesion property of PE cannot be expected without these processes. In this study, we suggest a simple, fast and cost-effective method to improve the adhesion properties of PE using a Kapton tape, which is a polyimide film generally used in flexible electronics. Specifically, by wrapping PE substrates applied with an adhesive using a Kapton tape and curing the sample using either a hot-press or a hot plate, the standard deviation of the shear strength decreased by 82.1% and 87.6%, respectively. To further improve the adhesion of PE substrates, we functionalized their surface using coupling agents, such as (3-glycidoxypropyl) methyldiethoxysilane and (3-aminopropyl) trimethoxysilane after an ultraviolet-ozone process. Using X-ray photoelectron spectroscopy and vacuum Fourier-transform infrared spectroscopy analysis, we proved that a significant improvement in the adhesion of PE occurred because of chemical crosslinking between either epoxy or amine groups functionalized on the PE substrates and epoxy-based adhesives comprising diglycidyl ether epoxy resin and triethylenetetramine hardener. This study is important, as it suggests a simple and very effective method to obtain highly reliable adhesion properties of PE using conventional adhesives. Kapton-taping can be a simple, yet very effective, method to achieve highly reliable adhesion properties of polyethylene substrates with conventional adhesives, resulting in a significant decrease in the standard deviation of shear strength, in comparison to other curing methods, such as hot plate and hot-press. • We demonstrated a method to improve the adhesion properties of polyethylene by simply wrapping samples using a Kapton tape. • Kapton taping method significantly lowered the standard deviation of the shear strength. • Functional groups that can be crosslinked with the main components of the adhesive greatly improved the adhesive properties. • The ultraviolet-ozone treatment was necessary for facile modification of coupling agents on bare PE surface.

The improvement of physicomechanical, flame retardant, and thermal properties of lignocellulosic material filled polymer composites

In this study, the effects of alkali and silane coupling agents and coir fiber (CF) loading on the fundamental properties of the CF-filled polypropylene (PP) composites were investigated. Mechanical properties of the PP/CF composites, such as tensile strength, tensile modulus, impact strength, and water absorption were increased by the increase of the CF loading. The inclusion of 3-aminopropyl trimethoxy silane (ATS) and tetramethoxy orthosilicate (TOS) after the alkali pretreatment for the CF increased all the mechanical properties and water desorption of the resulting composites. This trend was more evident with the increase in CF loading. The best results were obtained for PP/TOS composites as compared to other composites. SEM images of fractured samples show improved adhesion between CF and PP matrix after treatment with ATS and TOS. The horizontal rate of combustion is significantly reduced with the inclusion of Mg(OH)2 in PP/ATS and PP/TOS composites. DSC results show improved crystallization temperature, melting temperature, and melting enthalpy as compared with virgin PP. The addition of ATS and TOS after the alkali pretreatment improved the thermal stability of the resultant composites. TOS-modified CF composites showed better resistance than ATS-modified CF composites in water medium.

Atmospheric plasma sources for surface modifications in 3d printed scaffolds

In this work we investigate the coating of 3D-printed polymer structures with a robotic atmospheric pressure plasma jet with (3-aminopropyl)tri-methoxysilane. In particular, we investigated how deeply the coatings penetrate into the porous polymer structures and whether the nucleophilic groups are preserved. The influence of other process parameters (duty cycle, temperature, angle of the plasma jet to the substrate surface) is also discussed.

COOH-Terminated Silicon Quantum Dots as a Highly Efficient Drug Nanocarrier for Targeted Tumor Cell Imaging.

Fluorescent silicon quantum dots (SiQDs) characterized by exceptional photostability and colloidal robustness as well as beneficial biocompatibility are fast becoming new pharmaceutical nanocarriers. With a view to efficiently loading cisplatin (CDDP) onto SiQDs, carboxylate group (COOH) terminated SiQDs were imperative because of chelate formation with CDDP. In this work, we employed a facial microwave irradiation route for rapidly synthesizing high-quality COOH-SiQDs through the use of 3-aminopropyl trimethoxy silane (APTMS) molecules to fulfil the role of silicon precursor and maleic acid (MA) as the agent for facilitating reduction. The SiQDs showed blue fluorescence with an associated photoluminescence quantum yield (PLQY) of 40.2%, the size of which was small at 3.2 ±0.6 nm, and long-lasting stability (an extensive range in pH (4-12) and concentrations of electrolytes reaching 3 Molarity of a solution of sodium chloride). As nanocarriers, carboxylic acids chelation generated a high loading of CDDP onto SiQDs (drug loading capacity, DLC up to 32.2% at pH = 9) and a drug release of CDDP up to 57.6% at pH = 5. Furthermore, the MTT assays demonstrated the non or low cytotoxicity of SiQDs and the role of the controlled release of SiQD-CDDP Finally, the prepared SiQD-CDDP were used for cell imaging, and further targeted labeling of some tumors after folic acid (FA) conjugation. These characteristics allow for the deployment of SiQDs as a highly efficient nanocarrier that facilitate the delivery of clinical drugs for the future.

Three-dimensional macroscopic aminosilylated nanocellulose aerogels as sustainable bio-adsorbents for the effective removal of heavy metal ions

Designing an environmentally benign bio-adsorbent for the removal of heavy metal ions from aqueous medium was a sustainable strategy to ensure water safety. Herein, three-dimensional macroscopic aminosilyated nanocellulose aerogels (APTMS-modified TO-NFC) for the removal of heavy metal ions in water were successfully synthesized from bamboo-derived TEMPO-oxidized nanofibrillated cellulose (TO-NFC) and aminopropyltrimethoxysilane (APTMs) via a facile freeze-drying process. Owing to a relatively high BET surface area (129.32 m2 g−1), high porosity (99.14%) as well as high substitution degree of amino groups (0.41), the resulting APTMS-modified TO-NFC aerogel exhibited good adsorption capacity of 99.0, 124.5, and 242.1 mg g−1 for Cu2+, Cd2+ and Hg2+, respectively. Furthermore, the crosslinked and three-dimensionally porous architecture imparted it with relatively high compression strength, good excellent stability in water, and ease of recyclability from water after the usage. The pH value of the solution had a great influence on adsorption efficiency of the aerogel adsorbent, and optimal adsorption efficiency could be achieved at pH 3–7. Thermodynamic parameters suggested the spontaneous and endothermic nature of adsorption process. This work provides a facile method for preparing sustainable bio-adsorbent for effective heavy metal ions removal from aqueous medium.