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Stable electrodes are crucial for the practical applications of electrochemical systems. In this study, we report a simple method for synthesizing three-dimensional glassy-like carbon (3D·GC) on an alumina substrate through pyrolysis of benzyl alcohol and applying it to electrocatalytic reactions. Given its distinctive 3D morphology and stability in aqueous solution, the 3D·GC electrode exhibits significantly higher electrocatalytic activity than the commercial GC. Moreover, the rough surface of the 3D·GC electrode is favorable for direct immobilization of catalytic sites, such as metals (Au and Ag) and single-atom catalysts. The developed method for immobilizing single Ni sites is successfully applied to the 3D·GC electrode, resulting in the Ni SAC-3D·GC electrode that exhibits high CO selectivity and durability for electrochemical CO2 reduction. The Faradaic efficiency of CO is over 90% across a wide potential range. Due to direct immobilization, the Ni SAC-3D·GC electrode shows remarkable stability even after multiple reuse cycles, indicating its potential for long-term electrocatalytic applications. To gain an understanding of the mechanism underlying the high CO selectivity during CO2 reduction, the theoretical interactions between the individual Ni sites and the carbon substrate are explored. This theoretical analysis highlights the crucial role of the carbon substrate in stabilizing the COOH intermediate for electrochemical CO2 reduction under neutral conditions.

To extend the practicability of ceramics in immobilizing nuclear waste with fluctuant composition, structural design should be abandoned. The simulated tetravalent actinide waste An4+ (Ce4+) was directly doped into prepared Gd2Zr2O7, and the waste forms were synthesized by high‐temperature solid‐state reaction. It has been shown that the maximum loading of CeO2 in Gd2Zr2O7 lies between 20 and 30 wt.%, and Ce elements are uniformly distributed in the matrix. Existing in Ce3+ and Ce4+, cerium ions automatically occupied both the Gd and Zr sites in Gd2Zr2O7 according to valence equilibrium. This occupation causes the change of r(A3+)/r(B4+) and eventually leads to the structure transition from pyrochlore to fluorite. In addition, the normalized leaching rate of the sample with 60 wt.% of dopant was about 2.5 × 10−7 g m−2 d−1 on the 35th day. In this study, a free occupation of simulated waste ions in ceramics was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mass transfer-based heterogeneous photocatalysis for efficient energy transport. • Direct one-pot immobilization of iridium (III) complex via covalent linkage. • Fast mass transfer of reactants in hollow porous polystyrene nanospheres. • Crosslinking degree-dependent optical properties of anchored fac -Ir(ppy) 3. • Comparable catalytic activity to homogeneous fac -Ir(ppy) 3. Heterogeneous photocatalysis of iridium (III) complexes faces two major bottle-necks: limited mass/energy transfer and tedious immobilization. In this work, fac -Ir(ppy) 3 is directly anchored to hollow mesoporous polystyrene nanospheres (HMPNs) via one-pot F-C alkylation, achieving the covalent immobilization of fac -Ir(ppy) 3 at a low-cost. The thin shell, pores, hollow interior, and swelling property of HMPNs enable reactants to quickly access to fac -Ir(ppy) 3 , effectively avoiding energy loss in energy transport from excited fac -Ir(ppy) 3 * to reactants. The mass transfer of reactants and optical properties of fac -Ir(ppy) 3 such as quantum yield, luminescent lifetime and band gap energy closely depend on the cross-linking degree of polystyrene. The anchored fac -Ir(ppy) 3 exhibits comparable catalytic activity to homogeneous fac -Ir(ppy) 3 in heterogeneous [2 + 2] photodimerization of olefins with a good reusability without a significant decrease in yields over ten recycles. This work develops a strategy for fabricating efficient heterogeneous photocatalysts using available non-conjugated polymer as support based on the concept of fast mass transfer of reactants. [ABSTRACT FROM AUTHOR]

To investigate the change in biochar's ability to directly immobilize Cd in soil, a successive wheat cultivation experiment was conducted. Three biochars with different Cd adsorption mechanisms were added to the soils, and a mesh bag was used to separate the soil particles (> 1 μm) from the biochar. The results showed that the ash contents and anionic contents (CO32− and PO43−) of the biochar decreased with the cultivation time, while the oxygen-containing functional group content and CEC of the biochar increased. As a result, the Cd concentration on biochar decreased, by 68.9% for WBC300, while unstable Cd species (acid soluble and reducible fraction of Cd) on biochar increased with successive cultivation, increasing from 3 to 17% for WBC300 in FS. Correspondingly, the ability of biochar to inhibit Cd accumulation in wheat decreased. The results of this study illustrated that the ability of biochar to directly immobilize Cd in soil is not permanent; it gradually decreases with aging in soil. The adsorption mechanism of Cd on biochar changed from precipitation to complexation, and ion exchange processes could be the main reason. [ABSTRACT FROM AUTHOR]

Multi-component high-entropy pyrochlore (HEP) offers several advantages compared to single-component pyrochlore in solidifying radioactive waste, including the ability to solubilize multiple types of waste and lower leaching rates (LRs) of radionuclides. In this study, we successfully synthesized HEP (Y 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2) 2 Zr 2 O 7 and immobilized Ce, a simulated nuclide of Pu at 1500 °C for 48 h using a free occupied design approach. The Raman, XRD, and Rietveld refinement results showed that the immobilization limit for Ce fell between 20 wt.% and 30 wt.%. Notably, the ordered pyrochlore phase gradually transformed into the defective fluorite phase with an increase in Ce content. Moreover, the leaching tests demonstrated the excellent stability of the matrix, with the normalized LR for Ce reaching 10−7 g·m−2·L−1 after 42 days at 90 °C. These findings collectively suggest that HEP (Y 0.2 Nd 0.2 Sm 0.2 Eu 0.2 Gd 0.2) 2 Zr 2 O 7 holds promise as a substrate for immobilizing radioactive waste in the future. [ABSTRACT FROM AUTHOR]

Matrix-assisted pulsed laser evaporation (MAPLE) is an alternative and complimentary method to pulsed laser deposition. MAPLE has been demonstrated to be a less harmful approach for transporting and depositing delicate, highly sensitive molecules. Metalloproteins are considered sensitive molecules since their bioactivity is determined not only by their chemical structure but also by conformational changes that can be altered by deposition methods. Here we report a dataset of MAPLE deposition parameters of haemoglobin (Hb) that ensures the retention of its bioactivity. Methods for parameters optimization are also described. The data and analysis should be valuable for researchers interested in application of MAPLE techniques for metalloprotein immobilization since it provides a unique opportunity for direct immobilization. The data presents the results of previously conducted experiments on the basis of which is based the research article entitled “A Highly Efficient Biosensor based on MAPLE Deposited Hemoglobin on LPGs Around Phase Matching Turning Point” [1].

Immobilization of protein, compared to the use of free protein, offers improved stability, easy separation and continuous reusability. However, the classic routes for protein immobilization, based on non-specific adsorption, often negatively affect protein functionality. In this study, EctP1 peptide was explored as a novel short fusion tag for non-covalent adsorption on unmodified solid surfaces, silica and titania. A fusion of EctP1 with bovine carbonic anhydrase (BCA) was employed to investigate the optimal binding conditions that could diminish the nonspecific adsorption of Escherichia coli proteins. The stable binding of BCA-EctP1 on titania was observed in the pH range of 2–9, while the stable binding on silica was in the pH range 6–9. Moreover, the immobilized BCA-EctP1 on silica and titania particles showed enhanced thermal and storage stability and retained 95% of its residual activity after 5 uses. We further demonstrated the merits of the noncovalent immobilization of EctP1 fusion proteins to silica and titania in the recovery of the bound proteins. Interestingly, monomeric arginine showed better recovery yield of EctP1 fusion proteins (about 78–84%), compared to the recovery yield by the salts, NaCl and MgCl 2 (about 30–51%). Using BCA and monomeric red fluorescent protein (mRFP) as model proteins, the EctP1 fusion proteins were released in a biologically active form with approximately 80% recovery and 93% purity. Our approach is a simple and reproducible technique for direct immobilization of recombinant proteins from E. coli lysates on solid supports, with the potential high-purity recovery of recombinant proteins. Unlabelled Image • The EctP1 peptide served as a fusion tag for direct immobilization of recombinant proteins on unmodified silica and titania. • The immobilization of EctP1-tagged proteins was achieved with less nonspecific binding of Escherichia coli protein contaminants. • The immobilized EctP1-tagged proteins showed enhanced stability and reusability. • The EctP1 fusion proteins were recovered from the solid supports with 80% yield and 93% purity. [ABSTRACT FROM AUTHOR]

• Single, binary and ternary binders with at least 8% KY-2 have been well optimized. • Comparative leaching of 134Cs, 60Co and 152+154Eu radionuclides were assessed. • Leachability indexes were high and sometimes be twice the waste acceptance criteria. • The ternary binders were radiation stable while the solidified hot beads were not. • A three-step mechanism of such instability of the solidified hot beads was proposed. Individual metakaolin-based alkali activated binder (AAB) was utilized to optimize binary and ternary ones having f e l d s p a r / m e t a k a o l i n and s l a g / f e l d s p a r + m e t a k a o l i n ratios of 0.3 and 0.4, respectively. These three AABs had the ability to directly solidify 10.0 (FMK0-10R), 8.0 (FMK3-8R) and 12.0% (S4FMK3-12R) of the nuclear grade KY-2 beads, respectively, recording compressive strength values greater than twice the waste acceptance criteria. Leaching of 134Cs, 60Co and 152+154Eu, whether singularly or multiply loaded, was assessed. The multi-radionuclidic systems recorded greater leached fractions in the order of: 152+154Eu>134Cs>60Co. Among the studied systems, S4FMK3-12R formulations recorded the lowest diffusion coefficient values (D). Gamma-irradiation made a desired influence on all studied leaching systems with inverse relationships with the applied irradiation doses. Irradiating the optimized ternary AAB with 3.0 KGy (S4FMK3-12R-ɣ3) yielded the lowest D value (6.65 × 10−13 cm2/s), when single component-60Co was diffused. The leachability indexes of all irradiated AABs were not only greatly exceeded the value of 6 but also sometimes be twice such value. XRD, FT-IR and SEM examinations of S4FMK3, S4FMK3-12R and S4FMK3-12R-ɣ3 reflected their multi-layered semicrystalline natures and to what extent these AABs and the solidified beads had good and poor radiation stabilities, respectively, with a proposed three-step mechanism of such instability. [ABSTRACT FROM AUTHOR]

Stable electrodes are crucial for the practical applications of electrochemical systems. In this study, we report a simple method for synthesizing three-dimensional glassy-like carbon (3D·GC) on an alumina substrate through pyrolysis of benzyl alcohol and applying it to electrocatalytic reactions. Given its distinctive 3D morphology and stability in aqueous solution, the 3D·GC electrode exhibits significantly higher electrocatalytic activity than the commercial GC. Moreover, the rough surface of the 3D·GC electrode is favorable for direct immobilization of catalytic sites, such as metals (Au and Ag) and single-atom catalysts. The developed method for immobilizing single Ni sites is successfully applied to the 3D·GC electrode, resulting in the Ni SAC-3D·GC electrode that exhibits high CO selectivity and durability for electrochemical CO 2 reduction. The Faradaic efficiency of CO is over 90% across a wide potential range. Due to direct immobilization, the Ni SAC-3D·GC electrode shows remarkable stability even after multiple reuse cycles, indicating its potential for long-term electrocatalytic applications. To gain an understanding of the mechanism underlying the high CO selectivity during CO 2 reduction, the theoretical interactions between the individual Ni sites and the carbon substrate are explored. This theoretical analysis highlights the crucial role of the carbon substrate in stabilizing the COOH intermediate for electrochemical CO 2 reduction under neutral conditions. [Display omitted] • Three-dimensional glassy carbon is prepared through pyrolysis of benzyl alcohol. • The 3D·GC electrode is favorable for direct immobilization of catalytic sites. • The Ni SAC-3D·GC shows high CO selectivity and durability for CO 2 reduction. [ABSTRACT FROM AUTHOR]

Immobilization of proteins on a surface plasmon resonance (SPR) transducer is a delicate procedure since loss of protein bioactivity can occur upon contact with the untreated metal surface. Solution to the problem is the use of an immobilization matrix having a complex structure. However, this is at the expense of biosensor selectivity and sensitivity. It has been shown that the matrix-assisted pulsed laser evaporation (MAPLE) method has been successfully applied for direct immobilization (without a built-in matrix) of proteins, preserving their bioactivity. So far, MAPLE deposition has not been performed on a gold surface as required for SPR biosensors. In this paper we study the impact of direct immobilization of heme proteins (hemoglobin (Hb) and myoglobin (Mb)) on their bioactivity. For the purpose, Hb and Mb were directly immobilized by MAPLE technique on a SPR transducer. The bioactivity of the ligands immobilized in the above-mentioned way was assessed by SPR registration of the molecular reactions of various Hb/Mb functional groups. By SPR we studied the reaction between the beta chain of the Hb molecule and glucose, which shows the structural integrity of the immobilized Hb. A supplementary study of films deposited by FTIR and AFM was provided. The experimental facts showed that direct immobilization of an intact molecule was achieved.

Abstract Zearalenone (ZEN) is an important non-steroidal estrogenic mycotoxin produced by fusarium fungi species. A number of methods based on enzyme-linked immune assays (ELISA) and chromatographic approaches are available for the detection of ZEN. In this research, ZEN conjugated by bovine serum albumin (BSA) was immobilized on the surface of the screen-printed carbon electrode (SPCE) followed by the subsequent addition of anti-zearalenone monoclonal antibody (ZEN-MAb), alkaline phosphatase (ALP)-labeled secondary antibody, and 1-napthyl phosphate (1-NP) as a substrate. This immunosensor had good specificity, selectivity, reproducibility, and sensitivity for ZEN (LOD of 0.25 ng mL−1) when employed for quantification based on differential pulse voltammetry (DPV). This immunosensor yielded good recovery values in the range of 89–97% against real matrices (i.e., beer and wine samples) after spiking. This novel immunosensing principle can be extensively applied for the development of advanced sensing techniques for various analytes. [ABSTRACT FROM AUTHOR]

Rapid in-situ re-endothelialization of coronary stents is one of the most effective approaches to inhibit late thrombosis and restenosis. Strut surfaces allowing excellent adhesion and migration of endothelial cells and endothelial progenitor cells may accelerate in-situ re-endothelialization. Here, a well-known endothelial cell adhesive peptide, Arg-Glu-Asp-Val (REDV), was directly immobilized onto metallic surfaces by means of single-step tyrosine oxidation with copper chloride (II) and hydrogen peroxide, which we recently reported as a new biomaterial modification technique. REDV immobilization on a 316L stainless steel plate improved endothelial cell adhesion and effectively suppressed platelet adhesion in vitro. In addition, a Co-Cr stent immobilized with Ac-Tyr-Gly-Gly-Gly-Arg-Glu-Asp-Val (Y-REDV) was implanted into a rabbit abdominal aorta. On 7 days postimplantation, 80% of the strut surface of the Y-REDV-immobilized stent was covered by a thin neointimal layer and was similar in appearance to native endothelium. Restenosis and late thrombosis were not observed in the Y-REDV-immobilized stent for 42 days. These findings suggest that direct immobilization of Y-REDV peptide onto metallic biomaterials by tyrosine oxidation is effective for promoting in-situ re-endothelialization in vascular stents. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 491-499, 2018. [ABSTRACT FROM AUTHOR]

• Direct one-pot immobilization of chiral phosphine oxide via a covalent linkage. • Hollow porous polystyrene nanospheres as a platform for fast mass transfer. • Efficient heterogeneous enantioselective reductive aldol reaction. • Comparable catalytic performances to homogeneous asymmetric catalysis. The heterogeneous catalysis of expensive chiral phosphine oxides suffers from multi-step tedious immobilization and limited mass transfer due to its bulky volume. In this paper, a simple and direct strategy for covalently anchoring (S)-2,2′-bis(diphenylphosphino)-1,1′-binaphthyl dioxide (BINAPO) to hollow mesoporous polystyrene nanospheres (HMPNs) is developed to fabricate HMPNs-supported BINAPO (HMPNs@BINAPO) via one-pot Friedel-Crafts alkylation. HMPNs@BINAPO possesses a nanoscale and spherical morphology with a thin and mesoporous shell suitable for fast mass transfer of reactants and products. In the asymmetric reductive aldol reaction of α, β -unsaturated ketones and benzaldehydes with HSiCl 3 , HMPNs@BINAPO shows the comparable good to excellent catalytic performances to homogeneous BINAPO and good reusability without an obvious decrease in diastereoselectivity and enantioselectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: Lysosomal enzymes isolated from egg white were directly immobilized on titanium (IV) oxide (TiO2) particles using shaking methods (150rpm, room temperature, 10min), and the immobilization efficiency, activity, and stability of lysosomal enzymes immobilized on TiO2 were evaluated. Of the various mass ratios (w/w) of lysosomal enzymes to TiO2 tested, we found that 100% immobilization efficiency was observed at a ratio of 1:20 (enzymes:TiO2; w/w). Furthermore, the antimicrobial activities of the immobilized lysosomal enzymes were confirmed using viable cell counts against Escherichia coli. Our results showed that the antimicrobial activity of immobilized lysosomal enzymes is stable and can be maintained up to one month, but the antimicrobial activity of free enzymes without immobilization completely disappeared after five days in storage. In addition, enhanced immobilization efficiency was shown in TiO2 pretreated with a divalent, positively charged ion, Ca2+, and the antimicrobial activity for E. coli increased as a function of increasing ratio of immobilized enzymes. However, K+, a monovalent, positively charged ion, did not have any positive effect on immobilization or antimicrobial activity. Finally, we suggest that activity and stability of immobilized lysosomal enzymes can be maintained for a longer time than those properties of free lysosomal enzymes. [Copyright &y& Elsevier]

Methods of cellulase immobilization on magnetic particles via glutaraldehyde binding were studied. The binding was confirmed by transmission electronic microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and vibrating sample magnetometry (VSM). Samples analyzed by TEM and XRD showed that the magnetic particles with or without bound cellulase were all nanosized particles with a mean diameter of 11.5 nm, and the binding process did not cause significant changes in particle size and structure. Analysis by FTIR showed that the binding of cellulase to the magnetic nanoparticles might be via covalent bonding between residual amine groups on Fe3O4 nanoparticles and amine groups of the cellulase. The VSM analysis showed that magnetic nanoparticles with or without bound cellulase were all superparamagnetic. The immobilized cellulase had a wider pH and temperature range and improved storage stability compared with the free enzyme. Determination of the Michaelis constants revealed that the immobilized cellulase had a greater affinity for the cellulosic substrate than the free enzyme. The immobilized cellulase showed better performance on hydrolysis of steam-exploded corn stalks than of bleached sulfite bagasse pulp. [ABSTRACT FROM AUTHOR]

• Detection of MUC-1 is critical but difficult due to its trace amount in the serum of early cancer patients. • Dopamine can provide an amplified signal because of its electron donating capability. • Gelatin consists of excess of functional groups for specific immobilization support. • DA/MUC-1/fMWCNT nanoprobe provided an amplified current signal which was high enough to carry out the competition step with improved sensitivity. Mucin-1 (MUC-1) is associated with a broad range of human epithelia including gastric, lung and colorectal. In this work, a direct competitive electrochemical immunosensor based on gelatin modified transduction platform was designed. Dopamine (DA)/mucin-1 functionalized electro-active carbon nanotubes were employed as signal generating probes in the construction of electrochemical immunosensor for early stage diagnosis of breast cancer. The gelatin modified electrode served as a support to immobilize antibody (anti-MUC-1), while electrochemical response of functionalized electro-active carbon nano probes was used for quantitative measurement of MUC-1. Cyclic Voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) were carried out to characterize the transduction surface at different fabrication steps. The developed immunosensor permitted the detection of MUC-1 in the linear range of 0.05−940 U/mL, with a detection limit (LOD) of 0.01 U/mL. The immunosensor showed recovery values in the range of 96% for human serum sample analysis, demonstrating its practical applicability. [ABSTRACT FROM AUTHOR]

Immobilization of proteins on a surface plasmon resonance (SPR) transducer is a delicate procedure since loss of protein bioactivity can occur upon contact with the untreated metal surface. Solution to the problem is the use of an immobilization matrix having a complex structure. However, this is at the expense of biosensor selectivity and sensitivity. It has been shown that the matrix-assisted pulsed laser evaporation (MAPLE) method has been successfully applied for direct immobilization (without a built-in matrix) of proteins, preserving their bioactivity. So far, MAPLE deposition has not been performed on a gold surface as required for SPR biosensors. In this paper we study the impact of direct immobilization of heme proteins (hemoglobin (Hb) and myoglobin (Mb)) on their bioactivity. For the purpose, Hb and Mb were directly immobilized by MAPLE technique on a SPR transducer. The bioactivity of the ligands immobilized in the above-mentioned way was assessed by SPR registration of the molecular reactions of various Hb/Mb functional groups. By SPR we studied the reaction between the beta chain of the Hb molecule and glucose, which shows the structural integrity of the immobilized Hb. A supplementary study of films deposited by FTIR and AFM was provided. The experimental facts showed that direct immobilization of an intact molecule was achieved. [ABSTRACT FROM AUTHOR]