Effect of nitrogen atomic percentage on N+-bombarded MWCNTs in cytocompatibility and hemocompatibility

Nonthermal Plasma-Stimulated C-N Coupling from CH4 and N2 Depends on the Presence of Surface CHx and Plasma-Phase CN Species

Formation of C-N containing compounds from plasma-catalytic coupling of CH4 and N2 over various transition metals (Ni, Pd, Cu, Ag, and Au) is investigated using a multimodal spectroscopic approach, combining polarization-modulation infrared reflection-absorption spectroscopy (PM-IRAS) and optical emission spectroscopy (OES). Through sequential experiments utilizing CH4 and N2 nonthermal plasmas, we minimize plasma-phase reactions and identify key intermediates for C-N coupling on metal surfaces. Results show that simultaneous CH4 and N2 exposure with plasma stimulation produces surface C-N species. However, N2-CH4 sequential exposure does not lead to C-N species formation, while CH4-N2 sequential exposure reveals the presence of CHx surface species and CN radical species as key precursors to C-N species formation. From further analysis using X-ray photoelectron spectroscopy and liquid chromatography-mass spectrometry, the influence of exposure conditions on the degree of nitrogen incorporation and the nature of C-N species formed were revealed. The work highlights the importance of surface chemistry and exposure conditions in surface C-N coupling with plasma stimulation.

Linker Independent Regioselective Protonation Triggered Detoxification of Sulfur Mustards with Smart Porous Organic Photopolymer

The development of efficient metal-free photocatalysts for the generation of reactive oxygen species (ROS) for sulfur mustard (HD) decontamination can play a vital role against the stockpiling of chemical warfare agents (CWAs). Herein, one novel concept is conceived by smartly choosing a specific ionic monomer and a donor tritopic aldehyde, which can trigger linker-independent regioselective protonation/deprotonation in the polymeric backbone. In this context, the newly developed vinylene-linked ionic polymers (TPA/TPD-Ionic) are further explored for visible-light-assisted detoxification of HD simulants. Time-resolved-photoluminescence (TRPL) study reveals the protonation effect in the polymeric backbone by significantly enhancing the life span of photoexcited electrons. In terms of catalytic performance, TPA-Ionic outperformed TPD-Ionic because of its enhanced excitons formation and charge carrier abilities caused by the donor-acceptor (D-A) backbone and protonation effects. Moreover, the formation of singlet oxygen (1 O2 ) species is confirmed via in-situ Electron Spin Resonance (ESR) spectroscopy and density functional theory (DFT) analysis, which explained the crucial role of solvents in the reaction medium to regulate the (1 O2 ) formation. This study creates a new avenue for developing novel porous photocatalysts and highlights the crucial roles of sacrificial electron donors and solvents in the reaction medium to establish the structure-activity relationship.

Neutral - Eradication of As (III) and Congo red (CR) with green iron oxide (GIO) loaded chitosan(C) - (C - GIO) beads by a non - Thermal plasma jet via potential study

In this potential - study, the non - thermal atmospheric pressure plasma is utilized for the neutral - eradication of water contaminants. In the air ambient region, plasma induced reactive species, like as OH^•, O (O₂^-), H₂O₂ (OH^•+OH^•) & NO_x are performed for the oxidative and reductive transformation of As^III (H₃AsO₃) to As^V (H₂As O₄^-) & Fe₃O₄ (Fe³⁺) (C-GIO) to Fe₂O₃ (Fe²⁺). Whereas, the H₂O₂ & NO_x are quantified maximum (max.) in water, which is 144.24 & 111.82 μM, respectively. In the absence of plasma and plasma with C-GIO, the As^III was more eradicated, which is 64.01 and 100.00%. While, the C - GIO (catalyst) synergistic enhancement was performed and proved by the neutral - degradation of CR. Also, the As^V adsorbed on C-GIO adsorption capacity q_max and redox-adsorption yield were evaluated, which are 1.36 mg/g and 20.80 g/kWh, respectively. In this research, the waste material (GIO) was recycled, modified, and utilized for the neutral - eradication of water contaminates, which are organic (CR) and inorganic (As^III) toxicants by the controlling of H and OH^• under the interaction of plasma with catalyst (C-GIO). However, in this research, plasma can't adopt the acidic, which is controlled by the C-GIO via RONS. Moreover, in this eradicative study, various water pH alignments were performed, from neutral to acidic & neutral & base for toxicants removal. Furthermore, according to WHO norms, the arsenic level was reduced to 0.01 mg/l for environmental safety. The kinetic and isotherm studies were followed by the mono and multi-layer adsorption was performed on the surface of C - GIO beads, which is estimated by the fitting of rate limiting constant R² ≈ 1. Furthermore, the C-GIO was examined several characterizations alignments, such as crystal, surface, functional, elemental composition, retention time, mass spectrum, and elemental oriented properties. Overall, the suggested hybrid system is an eco-friendly pathway for the natural - eradication of contaminants, such as organic and inorganic compounds via waste material (GIO) recycling, modification, oxidation, reduction, adsorption, degradation, and neutralization phenomenon.

Iron Nanoparticles Wrapped with an N-Doped Carbon Material Produced by Using a Zinc Hydroxide Ferrocyanide Nanohybrid for Use in Commercial-like Supercapacitors

According to the technology of carbon-based supercapacitors, modifying the structure of carbon as an active electrode material leads to an increase in capacitance. A modification involves introducing heteroatoms such as nitrogen into the carbon structure and composing it with metals such as iron. In this research, an anionic source called ferrocyanide was used to produce N-doped carbon consisting of iron nanoparticles. In fact, ferrocyanide was located as a guest between the layers of a host material, which is zinc hydroxide in the α phase. This new nanohybrid material was then heat-treated under Ar, and the heated product after acid washing was iron nanoparticles wrapped with N-doped carbon materials. This material was used as an active material in the production of symmetric supercapacitors with different organic (TEABF₄ in acetonitrile) and aqueous (sodium sulfate) electrolytes as well as a new electrolyte (KCN in methanol). Accordingly, the supercapacitor made by the N/Fe-carbon active material and the organic electrolyte showed a capacitance value of 21 F/g at a current density of 0.1 A/g. This value is comparable to and even higher than the values observed in commercial supercapacitors.

Biocompatible Nanodiamonds Derived from Coal Washery Rejects: Antioxidant, Antiviral, and Phytotoxic Applications

Coal washery rejects (CWRs) are a major byproduct produced in coal washery industries. We have chemically derived biocompatible nanodiamonds (NDs) from CWRs toward a wide range of biological applications. The average particle sizes of the derived blue-emitting NDs are found to be in the range of 2-3.5 nm. High-resolution transmission electron microscopy of the derived NDs depicts the crystalline structure with a d-spacing of 0.218 nm, which is attributed to the 100 lattice plane of a cubic diamond. The Fourier infrared spectroscopy, zeta potential, and X-ray photoelectron spectroscopy (XPS) data revealed that the NDs are substantially functionalized with oxygen-containing functional groups. Interestingly, the CWR-derived NDs exhibit strong antiviral properties (high inhibition of 99.3% with an IC₅₀ value of 7.664 μg/mL) and moderate antioxidant activity that widen the possibility of biomedical applications. In addition, toxicological effects of NDs on the wheatgrass seed germination and seedling growth showed minimal inhibition (<9%) at the highest tested concentration of 300.0 μg/mL. The study also provides intriguing prospects of CWRs for the creation of novel antiviral therapies.

Wavelength engineerable porous organic polymer photosensitizers with protonation triggered ROS generation

Engineering excitation wavelength of photosensitizers (PSs) for enhanced reactive oxygen species (ROS) generation has inspired new windows for opportunities, enabling investigation of previously impracticable biomedical and photocatalytic applications. However, controlling the wavelength corresponding to operating conditions remains challenging while maintaining high ROS generation. To address this challenge, we implement a wavelength-engineerable imidazolium-based porous organic photocatalytic ROS generation system (KUP system) via a cost-effective one-pot reaction. Remarkably, the optimal wavelength for maximum performance can be tuned by modifying the linker, generating ROS despite the absence of metal ions and covalently attached heavy atoms. We demonstrate that protonated polymerization exclusively enables photosensitization and closely interacts with oxygen related to the efficiency of photosensitizing. Furthermore, superior tumor eradication and biocompatibility of the KUP system were confirmed through bioassays. Overall, the results document an unprecedented polymerization method capable of engineering wavelength, providing a potential basis for designing nanoscale photosensitizers in various ROS-utilizing applications.

Novel Antitumor Agents Based on Fluorescent Benzofurazan Derivatives and Mesoporous Silica

Two novel fluorescent mesoporous silica-based hybrid materials were obtained through the covalent grafting of [4-hydrazinyl-7-nitrobenz-[2,1,3-d]-oxadiazole (NBDH) and N¹-(7-nitrobenzo[c][1,2,5]-oxadiazol-4-yl) benzene-1,2-diamine (NBD-PD), respectively, inside the channels of mesoporous silica SBA-15. The presence of fluorescent organic compounds (nitrobenzofurazan derivatives) was confirmed by infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermal analysis (TG), and fluorescence spectroscopy. The nitrogen physisorption analysis showed that the nitrobenzofurazan derivatives were distributed uniformly on the internal surface of SBA-15, the immobilization process having a negligible effect on the structure of the support. Their antioxidant activity was studied by measuring the ability to reduce free radicals DPPH (free radical scavenging activity), in order to formulate potential applications of the materials obtained. Cytotoxicity of the newly synthesized materials, SBA-NBDH and SBA-NBD-PD, was evaluated on human B16 melanoma cells. The morphology of these cells, internalization and localization of the investigated materials in melanoma and fibroblast cells were examined through fluorescence imaging. The viability of B16 (3D) spheroids after treatment with SBA-NBDH and SBA-NBD-PD was evaluated using MTS assay. The results showed that both materials induced a selective antiproliferative effect, reducing to various degrees the viability of melanoma cells. The observed effect was enhanced with increasing concentration. SBA-NBD-PD exhibited a higher antitumor effect compared to SBA-NBDH starting with a concentration of 125 µg/mL. In both cases, a significantly more pronounced antiproliferative effect on tumor cells compared to normal cells was observed. The viability of B16 spheroids dropped by 40% after treatment with SBA-NBDH and SBA-NBD-PD at 500 µg/mL concentration, indicating a clear cytotoxic effect of the tested compounds. These results suggest that both newly synthesized biomaterials could be promising antitumor agents for applications in cancer therapy.

Corrosion Mitigation Performance of N80 Steel in 5% Sulfamic Acid Medium by Applying Novel Tetrahydro-1,2,4-triazines Including Triazene Moieties: Electrochemical and Theoretical Approaches

We observed our newly developed tetrahydro-1,2,4-triazines, including triazene moieties (THTA), namely, 6-((1E)-1-((2E)-(4-(((Z)-1-(2,4-diphenyl-2,3,4,5-tetrahydro-1,2,4-triazin-5-yl) ethylidene) triaz-1-en-1-yl)piperazin-1-yl) triaz-2-en-1-ylidene) ethyl)-2,4-diphenyl-2,3,4,5-tetrahydro-1,2,4-triazine (THTA-I), and 1-((E)-((E)-1-(2,4-diphenyl-2,3,4,5-tetrahydro-1,2,4-triazin-6-yl) ethylidene) triaz-1-en-1-yl) naphthalen-2-ol (THTA-II), as effective inhibitors for the corrosion protection of N80 carbon steel metal in 5% sulfamic acid as the corrosive medium via electrochemical approaches such as potentiodynamic polarization and electrochemical impedance spectroscopy. Furthermore, the tested steel exterior was monitored using X-ray photoelectron spectroscopy after the treatment with the investigated components to verify the establishment of the adsorbed shielding film. The investigated compounds acted as mixed-type inhibitors, as shown by Tafel diagrams. The compounds considered obey the Langmuir adsorption isotherm, and their adsorption on the steel surface was chemisorption. When the tested inhibitors were added, the double-layer capacitances, which can be determined by the adsorption of the tested inhibitors on N80 steel specimens, decreased compared with that of the blank solution. At 10^-4 M, the inhibitory efficacy of THTA-I and THTA-II achieved maximum values of 88.5 and 86.5%, respectively. Density-functional theory computations and Monte-Carlo simulation were applied to determine the adsorption attributes and inhibition mechanism through the studied components. Furthermore, the investigated inhibitors were considered to adsorb on the Fe (1 1 0) surface. The adsorption energy was then measured on steel specimens.

Application of non-metal nanoparticles, as a novel approach, for improving the stability of blood products: 2011-2021

Despite the importance of the proper quality of blood products for safe transfusion, conventional methods for preparation and their preservation, they lack significant stability. Non-metal nanoparticles with particular features may overcome these challenges. This review study for the first time provided a comprehensive vision of the interaction of non-metal nanoparticles with each blood product (red blood cells, platelets and plasma proteins). The findings of this review on the most effective nanoparticle for improving the stability of RBCs indicate that graphene quantum dots and nanodiamonds show compatibility with RBCs. For increasing the stability of platelet products, silica nanoparticles exhibited a suppressive impact on platelet aggregation. Pristine graphene also shows compatibility with platelets. For better stability of plasma products, graphene oxide was indicated to preserve free human serum albumin from thermal shocks at low ionic strength. For increased stability of Factor VIII, mesoporous silica nanoparticles with large pores exhibit the superb quality of recovered proteins. Furthermore, 3.2 nm quantum dots exhibited anticoagulant effects. As the best promising nanoparticles for immunoglobulin stability, graphene quantum dots showed compatibility with γ-globulins. Overall, this review recommends further research on the mentioned nanoparticles as the most potential candidates for enhancing the stability and storage of blood components.

Synthesis and characterization of novel dicarbohydrazide derivatives with electrochemical and theoretical approaches as potential corrosion inhibitors for N80 steel in a 3.5% NaCl solution

Two novel ethanoanthracene-11,12-dicarbohydrazide derivatives N'11,N'12-bis((Z)-4-hydroxybenzylidene)-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarbohydrazide (H2HEH) and N'11,N'12-bis((Z)-4-methoxybenzylidene)-9,10-dihydro-9,10-ethanoanthracene-11,12-dicarbohydrazide (H2MEH) were synthesized and characterized by FT-IR spectroscopy, electronic spectra, and NMR spectroscopy. These two derivatives as novel anticorrosion inhibitors for N80 steel in a 3.5% NaCl solution were studied using electrochemical techniques including potentiodynamic polarization (PP), electrochemical impedance spectroscopy (EIS), and electrochemical frequency modulation (EFM). Corrosion parameters and adsorption isotherms were determined from current-potential diagrams (i.e., Tafel slopes). The impact of temperature and inhibitor concentration on the corrosion performance was studied using the PP method. The PP results suggested mixed-type inhibitors. The inhibition prohibition increased and decreased when the dose was increased and the temperature was increased, respectively. The adsorption of the hydrazides on the N80 exterior followed the Langmuir isotherm. The maximum inhibition proficiency for H2MEH and H2HEH were 93.3% and 92.2%, respectively, at 1 × 10-4 M. Moreover, the investigated surface was studied with the synthesized compounds through X-ray photoelectron spectroscopy (XPS) to confirm the construction of an adsorbed shielding barrier. An evident association was established between the corrosion inhibition proficiency and theoretical variables acquired using the density functional theory (DFT) method and Monte Carlo (MC) simulations. The experimental data were in good agreement with the theoretical results.

Optical and Physicochemical Characterizations of a Cellulosic/CdSe-QDs@S-DAB5 Film

CdSe quantum dots nanoparticles were coated with the thiolated (DiAminoButane based dendrimer) DAB dendrimer of fifth generation (S-DAB₅) and embedded in a highly hydrophilic regenerated cellulose (RC) film by simple dip-coating method (immersion in QD-dendrimer aqueous solution) as a way to get a flexible nano-engineered film (RC-4/CdSe-QDs@S-DAB₅) with high transparency and photoluminescence properties for different applications. Optical changes in the RC film associated with QDs inclusion were determined by spectroscopic ellipsometry (SE) measurements, which provide information on changes caused in the refraction index and the extinction coefficients of the film, as well as by light transmittance/reflectance curves and photoluminescence (PL) spectra. Impedance spectroscopy (IS) and other typical physicochemical techniques for material characterization (TEM, SEM and XPS) have also been used in order to have more complete information on film characteristics. A comparison of RC-4/CdSe-QDs@S-DAB₅ film optical characteristics with those exhibited by other RC-modified films depending on the type of dendrimer was also carried out.

Facile synthesis of ZnO-SnO2 anchored ZIF-8 nanocomposite: a potential photocatalyst

For the first time, ZnO-SnO₂ nanocomposite has been anchored (ZS@Z) on ZIF-8 (zeolitic imidazolate framework) surface and encapsulated (ZS@Z1, ZS@Z2 and ZS@Z3) within ZIF-8 matrix during the in situ synthesis of ZIF-8. ZnO-SnO₂ nanocomposites were synthesized in various molar ratio of Zn and Sn, i.e. 1:1, 2:8, 4:6, 6:4 and 8:2 (abbreviated as ZS-11, ZS-28, ZS-46, ZS-64 and ZS-82) using sol-gel and by grinding method (abbreviated as ZS-A, ZS-B, ZS-C, ZS-D and ZS-E). As-synthesized ZnO-SnO₂ nanocomposites have been well characterized using various spectroscopic techniques. Further, ZS-E nanocomposite was succesfully anchored and encapsulated within ZIF-8 due to its good photocatalytic activity. Morphology of ZnO-SnO₂ nanocomposites and their composites (ZS@Z, ZS@Z1, ZS@Z2 and ZS@Z3) was ensured by SEM (scanning electron microscopy) and TEM (transmission electron microscopy) images. The lowering of band gap of ZIF-8 from 5.2 to 3.25/3.79 eV confirmed the proper anchored ZnO-SnO₂@ZIF-8. Moreover, XPS analysis was also performed for the analysis of elemental composition of composites. In order to validiate thier photocatalytic application, adsorption capacity and photodegradation efficiency have been examined using methylene blue (MB) as model pollutant. It has been found that 10 mg of ZnO-SnO₂ nanocomposite (ZS-E) exhibits maximum photodegradation efficiency (58.68%) towards MB ([MB] = 1.6 mg L^-1) at pH = 7.89 while ZS@Z, ZS@Z1, ZS@Z2 and ZS@Z3 composites (10 mg, 0.5 mg mL^-1) can degrade off 100%, 93%, 97% and 92% MB, respectively. Hence, ZS@Z, ZS@Z1, ZS@Z2 and ZS@Z3 composites exhibit enhanced photodegradation efficiency as compared to ZIF-8 and ZnO-SnO₂ nanocomposites and can be used for water remediation.

Protection of LiFePO4 against Moisture

In this study, a carbon-coated LiFePO₄ (LFP/C) powder was chemically grafted with trifluoromethylphenyl groups in order to increase its hydrophobicity and to protect it from moisture. The modification was carried out by the spontaneous reduction of in situ generated 4-trifluoromethylphenyl ions produced by the diazotization of 4-trifluoromethylaniline. X-ray photoelectron spectroscopy was used to analyze the surface organic species of the modified powder. The hydrophobic properties of the modified powder were investigated by carrying out its water contact angle measurements. The presence of the trifluoromethylphenyl groups on the carbon-coated LiFePO₄ powder increased its stability in deionized water and reduced its iron dissolution in the electrolyte used for assembling the battery. The thermogravimetric and inductively coupled plasma atomic emission spectroscopy analyses revealed that 0.2–0.3 wt.% Li was deinserted during grafting and that the loading of the grafted molecules varied from 0.5 to 0.8 wt.% depending on the reaction conditions. Interestingly, the electrochemical performance of the modified LFP/C was not adversely affected by the presence of the trifluoromethylphenyl groups on the carbon surface. The chemical relithiation of the grafted samples was carried out using LiI as the reducing agent and the lithium source in order to obtain fully lithiated grafted powders.

Autologous protein-based scaffold composed of platelet lysate and aminated hyaluronic acid

This study describes a protein-based scaffold using platelet rich plasma (PRP), aminated hyaluronic acid (HA-NH₂) and Genipin for potential use in regenerative applications as an autologous tissue engineering scaffold. Human PRP was subjected to three freeze-thaw cycles for obtaining platelet lysates (PL). HA-NH₂ was synthesized from hyaluronic acid. PL/HA-NH₂ scaffolds were fabricated using different concentrations of genipin (0.05, 0.1 and 0.2%) and HA-NH₂ (10, 20 and 30 mg/mL). Mechanical, physical, and chemical properties of the scaffolds were comprehensively investigated. The compressive test findings revealed that crosslinking with 0.1 and 0.2% genipin improved the mechanical properties of the scaffolds. SEM evaluations showed that the scaffolds exhibited an interconnected and macroporous structure. Besides, porosimetry analysis indicated a wide distribution of the scaffold pore-size. Rheological findings demonstrated that the G' values were higher than the G″ values, indicating that PL/HA-NH₂ scaffolds had typical viscoelastic properties. In vitro biocompatibility studies showed that the scaffolds were both cytocompatible and hemocompatible. Alamar Blue test indicated that human adipose mesenchymal stem cells (hASCs) were able to attach, spread and proliferate on the scaffolds for 21 days-duration. Our findings clearly indicate that PL/HA-NH₂ can be a promising autologous candidate scaffold for tissue engineering applications.

A new bifunctional heterogeneous nanocatalyst for one-pot reduction-Schiff base condensation and reduction–carbonylation of nitroarenes

In this work, synthesis of Pd–NHC-γ-Fe₂O₃-n-butyl-SO₃H and its activity as a bifunctional heterogeneous nanocatalyst containing Pd–NHC and acidic functional groups, are described. This newly synthesized nanomagnetic catalyst is fully characterized by different methods such as FT-IR, XPS, TEM, VSM, ICP and TG analysis. At first, the catalytic activity of Pd–NHC-γ-Fe₂O₃-n-butyl-SO₃H is evaluated for the reduction of nitroarenes in aqueous media using NaBH₄ as a clean source of hydrogen generation at ambient temperature. Using the promising results obtained from the nitroarene reduction, this catalytic system is used for two one-pot protocols including reduction-Schiff base condensation and reduction–carbonylation of various nitroarenes. In these reactions the in situ formed amines are further reacted with aldehydes to yield imines or carbonylated to amides. The desired products are obtained in good to high yields in the presence of Pd–NHC-γ-Fe₂O₃-n-butyl-SO₃H as a bifunctional catalyst. The catalyst is reused with the aid of a magnetic bar for up to six consecutive cycles without any drastic loss of its catalytic activity.

This paper presents synthesis of Pd–NHC-γ-Fe₂O₃-n-butyl-SO₃H and its activity as bifunctional heterogeneous nanocatalyst containing Pd–NHC and acidic functional groups.

Magnetic Nanoparticles Conjugated with Peptides Derived from Monocyte Chemoattractant Protein-1 as a Tool for Targeting Atherosclerosis

Atherosclerosis is a multifactorial inflammatory disease that may progress silently for long period, and it is also widely accepted as the main cause of cardiovascular diseases. To prevent atherosclerotic plaques from generating, imaging early molecular markers and quantifying the extent of disease progression are desired. During inflammation, circulating monocytes leave the bloodstream and migrate into incipient lipid accumulation in the artery wall, following conditioning by local growth factors and proinflammatory cytokines; therefore, monocyte accumulation in the arterial wall can be observed in fatty streaks, rupture-prone plaques, and experimental atherosclerosis. In this work, we synthesized monocyte-targeting iron oxide magnetic nanoparticles (MNPs), which were incorporated with the peptides derived from the chemokine receptor C-C chemokine receptor type 2 (CCR2)-binding motif of monocytes chemoattractant protein-1 (MCP-1) as a diagnostic tool for potential atherosclerosis. MCP-1-motif MNPs co-localized with monocytes in in vitro fluorescence imaging. In addition, with MNPs injection in ApoE knockout mice (ApoE KO mice), the well-characterized animal model of atherosclerosis, MNPs were found in specific organs or regions which had monocytes accumulation, especially the aorta of atherosclerosis model mice, through in vivo imaging system (IVIS) imaging and magnetic resonance imaging (MRI). We also performed Oil Red O staining and Prussian Blue staining to confirm the co-localization of MCP-1-motif MNPs and atherosclerosis. The results showed the promising potential of MCP-1-motif MNPs as a diagnostic agent of atherosclerosis.

Protein-Substrate Adhesion in Microcontact Printing Regulates Cell Behavior

Microcontact printing (μCP) is widely used to create patterns of biomolecules essential for studies of cell mechanics, migration, and tissue engineering. However, different types of μCPs may create micropatterns with varied protein-substrate adhesion, which may change cell behaviors and pose uncertainty in result interpretation. Here, we characterize two μCP methods for coating extracellular matrix (ECM) proteins (stamp-off and covalent bond) and demonstrate for the first time the important role of protein-substrate adhesion in determining cell behavior. We found that, as compared to cells with weaker traction force (e.g., endothelial cells), cells with strong traction force (e.g., vascular smooth muscle cells) may delaminate the ECM patterns, which reduced cell viability as a result. Importantly, such ECM delamination was observed on patterns by stamp-off but not on the patterns by covalent bonds. Further comparisons of the displacement of the ECM patterns between the normal VSMCs and the force-reduced VSMCs suggested that the cell traction force plays an essential role in this ECM delamination. Together, our results indicated that μCPs with insufficient adhesion may lead to ECM delamination and cause cell death, providing new insight for micropatterning in cell-biomaterial interaction on biointerfaces.

N+ implantation induce cytocompatibility of shape-controlled three-dimensional self-assembly graphene

AIM

The aim of the present research was to synthesize N⁺ implanted 3D self-assembly graphene (N⁺/3D-SGHs) to overcome the weaknesses of graphene (small sizes and poor hydrophilicity) in tissue engineering scaffolds.

MATERIALS & METHODS

N⁺/3D-SGHs was achieved by ion implantation on one-step hydrothermal synthesized 3D self-assembly graphene (3D-SGHs), and N⁺/3D-SGHs with different doses of nitrogen ions (1 × 10¹⁶ ions/cm², 1 × 10¹⁸ ions/cm² and 1 × 10²⁰ ions/cm²), which adjusted by nitrogen ion beam intensity.

RESULTS

N⁺/3D-SGHs, as scaffolds, provide stereo space and hydrophilic groups for mouse-fibroblast cells (L929) growth and proliferation. Notably, N⁺/3D-SGHs with the N⁺ injected quantity of 1 × 10²⁰ ions/cm² displayed the highest protein-adhesion strength, cell viability and proliferation, which supported its good cytocompatibility.

CONCLUSION

This study demonstrated N⁺/3D-SGHs as a promising and effective tissue scaffold that might have applications in biomedicine.

Enhancement of interaction of L-929 cells with functionalized graphene via COOH+ ion implantation vs. chemical method

Low hydrophilicity of graphene is one of the major obstacles for biomaterials application. To create some hydrophilic groups on graphene is addressed this issue. Herein, COOH+ ion implantation modified graphene (COOH+/graphene) and COOH functionalized graphene were designed by physical ion implantation and chemical methods, respectively. The structure and surface properties of COOH+/graphene and COOH functionalized graphene were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Compared with graphene, COOH+/graphene and COOH functionalized graphene revealed improvement of cytocompatibility, including in vitro cell viability and morphology. More importantly, COOH+/graphene exhibited better improvement effects than functionalized graphene. For instance, COOH+/graphene with 1 × 1018 ions/cm2 showed the best cell-viability, proliferation and stretching. This study demonstrated that ion implantation can better improve the cytocompatibility of the graphene.

Bioinorganic Nanohybrid Catalyst for Multistep Synthesis of Acetaminophen, an Analgesic

A bioinorganic nanohybrid catalyst was synthesized by combining esterase with a platinum nanoparticle (PtNP). The combination of two catalysts resulted in enhanced catalytic activities, esterase hydrolysis, and hydrogenation in PtNPs, as compared to each catalyst alone. This hybrid catalyst can be successfully used in the multistep synthesis of acetaminophen (paracetamol), an analgesic and antipyretic drug, in a one-pot reaction with high yield and efficacy within a short time, demonstrating that the nanobiohybrid catalyst offers advantages in the synthesis of fine chemicals in industrial applications.

The enhanced anticoagulation for graphene induced by COOH(+) ion implantation

Graphene may have attractive properties for some biomedical applications, but its potential adverse biological effects, in particular, possible modulation when it comes in contact with blood, require further investigation. Little is known about the influence of exposure to COOH(+)-implanted graphene (COOH(+)/graphene) interacting with red blood cells and platelets. In this paper, COOH(+)/graphene was prepared by modified Hummers' method and implanted by COOH(+) ions. The structure and surface chemical and physical properties of COOH(+)/graphene were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Systematic evaluation of anticoagulation, including in vitro platelet adhesion assays and hemolytic assays, proved that COOH(+)/graphene has significant anticoagulation. In addition, at the dose of 5 × 10(17) ions/cm(2), COOH(+)/graphene responded best on platelet adhesion, aggregation, and platelet activation.