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According to current research, cancer cell growth is suppressed by ω-3 fatty acids, which are essential fatty acids. On the other hand, ω-3 fatty acids are metabolized to bioactivities in vivo. A systematic evaluation of the ability of ω-3 fatty acids and their metabolites to suppress cancer cell growth has not been sufficiently conducted. Our work evaluated the effect of ω-3 fatty acids (docosahexaenoic acid, eicosapentaenoic acid), trans fatty acid, and the metabolites (Resolvin E1, Maresin 1) on cancer cell growth suppressibility. Our results suggest that there may be optimal fatty acids depending on the kind of cancer cells, the presence or absence of hydroxyl group, and the double bond structure involved.

The optimal conditions for fabricating a screen-printed diamond electrode for the sensitive detection of l -cysteine (Cys), a non-essential amino acid, were investigated. As-grown (AG-), hydrogen-terminated (H-) and oxygen-terminated boron-doped diamond powders (O-BDDP) were prepared, and BDDP-printed electrodes were fabricated using BDDP-containing inks. Comparing the linear sweep voltammograms of Cys at AG-BDDP-, H-BDDP-, and O-BDDP-printed electrodes, among the three samples, the H-BDDP-printed electrode was found to be the most suitable for the sensitive detection of Cys at low concentrations, showing a steep slope in its calibration curve and a low background current density. In addition, the H-BDDP-printed electrode exhibited a lower limit of detection (0.620 μM) and a more negative oxidation peak potential (+0.663 V vs. Ag/AgCl) and wider linear concentration range (1–194 μM) than a H-boron-doped diamond (BDD) thin-film electrode. It is thought that a slight amount of sp2 carbon on the BDDP contributed to these optimal properties. Using the H-BDDP-printed electrode, Cys was detected in a solution containing electroactive interferents (glutathione and methionine) with a recovery of 86–104%. Therefore, it was concluded that the H-BDDP-printed electrode can be used as a highly sensitive and disposable electrochemical sensor for Cys detection.

This study investigates the effect of chemical surface termination on the electrochemical characteristics of boron-doped diamond powder (BDDP). The aim is to realize highly sensitive electrochemical detection of ciprofloxacin (CIP) on BDDP-printed electrodes. To this end, we prepared oxygen-terminated BDDP (O-BDDP) and hydrogen-terminated BDDP (H-BDDP), and mixed them with an insulating polyester (PES) resin binder to obtain BDDP ink for the printed electrode. Scanning electron microscopy of the BDDP-printed electrodes revealed that the O-BDDPs were partially covered with PES resin, while the H-BDDPs were entirely covered with resin. This structural difference might explain the lower charge-transfer resistance of the Ru(NH3)62+/3+ redox reaction at the O-BDDP-printed electrode than at the H-BDDP-printed electrode. The slope of the calibration curve of the linear sweep voltammogram of CIP was steeper at the O-BDDP-printed electrode than at the H-BDDP-printed electrode and the O-BDD thin-film electrode, and was similar to that at the H-BDD thin-film electrode. Using the O-BDDP-printed electrode, we determined the CIP in artificial buffer-diluted urine in the concentration range 1–30 μM with a recovery of 107%. We conclude that the O-BDDP-printed electrodes provide a highly sensitive and disposable electrochemical sensor for CIP detection.

Boron-doped diamond (BDD) electrodes have a wide potential window and can produce ozone by water electrolysis at high voltage. Though ozone has strong oxidative power (standard oxidation potential: 2.07 V vs. NHE), it cannot decompose certain types of recalcitrant organic matter completely. We developed an advanced oxidation process (AOP), in which hydroxy radicals with stronger oxidative power (standard oxidation potential: 2.85 V vs. NHE) are formed using a combination of ozone, photocatalyst, and UV. In this study, we fabricated a mesoporous TiO2/BDD hybrid electrode and examined its potential for AOPs. A synergetic effect between electrochemical water treatment and photocatalytic water treatment was observed with the hybrid electrode that did not occur with the BDD electrode.

Ammonium ions were formed by electrochemical oxidation of urea with a boron-doped diamond (BDD) electrode. Almost complete decomposition of urea was achieved. When the BDD electrode was used together with a mesoporous titanium dioxide photocatalyst, the amount of ammonium ions produced increased.

A simple water treatment system consisting of a deep UV light (λ = 222 nm) source, a mesoporous TiO2/boron-doped diamond (BDD) photocatalyst, and a BDD electrode was prepared and used to decompose sulfamethoxazole (SMX) in an advanced oxidation process. The mesoporous TiO2/BDD photocatalyst used with the electrochemical treatment promoted SMX decomposition, but the mesoporous TiO2/BDD photocatalyst alone had a similar ability to decompose SMX as photolysis. Fragments produced through photocatalytic treatment were decomposed during the electrochemical treatment and fragments produced during the electrochemical treatment were decomposed during the photocatalytic treatment, so performing the electrochemical and photocatalytic treatments together effectively decomposed SMX and decrease the total organic carbon concentration to a trace.

Porphyrin selectively shows tumour accumulation and has attracted attention as a carrier molecule for drug delivery systems (DDS). Porphyrin has two functional sites termed the meso- and β-positions. In previous work, meso-porphyrin derivatives with an alkyl group were found to exhibit greater accumulation in human breast cancer cells (MCF-7). To identify the correlation between porphyrin accumulation and functional porphyrin positions of other functional groups, the accumulation of porphyrin derivatives with a phenyl group was investigated. The β-porphyrin derivative with a phenyl group showed higher accumulation in MCF-7 cells and greater affinity for albumin than the meso-porphyrin derivative. The results of density functional theory (DFT) calculations suggest that the β-porphyrin derivative with a phenyl group had higher planarity across the total structure than the meso-porphyrin derivative. It was concluded that the greater planarity of the β-porphyrin derivative with a phenyl group might lead to superior MCF-7 cell accumulation.

Lightning strikes cause nitrogen to dissolve in water and form reactive nitrogen and oxygen species, which form natural fertilizers that can be absorbed through plant roots. Such processes during rainstorm events can be simulated by applying plasma to a solution. Plasma-activated water (PAW) has great potential as a source of various dissolved reactive chemical species. Different mixtures of species are produced using different solution compositions. Here, basil seeds were grown in PAW to prevent blooms of

Here, we report the first synthesis of polycrystalline boron-doped diamond (BDD) by an In-liquid microwave plasma CVD (IL-MPCVD) process from a mixture of alcohols and boron trioxide (B2O3). We simultaneously achieved high growth rates (up to 287 μm/h) and high boron concentrations (up to 7 × 1021 cm−3). We examined the growth mechanism and show that water generated by dissolution of B2O3 in the alcohol is key to rapid growth of BDD. Even with the same C:H:O ratio, diamond growth rate and nucleation density drastically decreased by addition of water. Water has a strong etching effect, which shifts diamond to grow in carbon rich conditions. Finally, we evaluated the as-grown BDD film as a diamond electrode. Our IL-MPCVD-grown BDD showed electrochemical properties comparable to those of BDD grown by the conventional CVD process in terms of its potential window (3.2 V) and peak separation (85 mV) in 1 mM K3[Fe(CN)6]. Owing to the high growth rate, IL-MPCVD is an effective technique for synthesizing BDD.

Herein, a conductive boron-doped nanodiamond (BDND) particle is prepared as an electrode material for an aqueous electric double-layer capacitor with high power and energy densities. The BDND is obtained by depositing a boron-doped diamond (BDD) on a nanodiamond particle substrate with a primary particle size of 4.7 nm via microwave plasma-assisted chemical vapor deposition, followed by heat treatment in air. The BDND comprises BDD and sp

In this research work, we reported the synthesis of a spherical-shaped bismuth vanadate (BiVO4) photocatalyst using a cost-effective, simple, chemical hydrothermal method and studied the effect of deposition temperatures on the structural, morphological, optical properties, etc. The XRD result confirmed the monoclinic scheelite phase of BiVO4. An XPS study confirmed the occurrence of Bi, V, and O elements and also found that Bi and V exist in +3 and +5 oxidation states, respectively. SEM micrographs revealed the spherical-shaped morphology of the BiVO4 photocatalyst. Optical investigation showed that the bandgap of the BiVO4 photocatalyst varied between 2.25 and 2.32 eV. The as-synthesized BiVO4 photocatalyst was used to study the photocatalytic degradation of crystal violet (CV) dye under visible light illumination. The photocatalytic degradation experiment showed that the degradation percentage of crystal violet dye using BiVO4 reached 98.21% after 120 min. Mineralization of crystal violet dye was studied using a chemical oxygen demand analysis.

Porphyrin derivatives accumulate selectively in cancer cells and are can be used as carriers of drugs. Until now, the substituents that bind to porphyrins (mainly at the meso-position) have been actively investigated, but the effect of the functional porphyrin positions (β-, meso-position) on tumor accumulation has not been investigated. Therefore, we investigated the correlation between the functional position of substituents and the accumulation of porphyrins in cancer cells using cancer cells. We found that the meso-derivative showed higher accumulation in cancer cells than the β-derivative, and porphyrins with less bulky substituent actively accumulate in cancer cells. When evaluating the intracellular distribution of porphyrin, we found that porphyrin was internalized by endocytosis and direct membrane permeation. As factors involved in these two permeation mechanisms, we evaluated the affinity between porphyrin-protein (endocytosis) and the permeability to the phospholipid bilayer membrane (direct membrane permeation). We found that the binding position of porphyrin affects the factors involved in the transmembrane permeation mechanisms and impacts the accumulation in cancer cells.

Understanding the fundamentals of photoelectrocatalytic (PEC) biomolecular oxidation benefits the development of next-generation PEC biosensors. In this work, single-step electrospun titanium-di-oxide-gold (TiO

Porphyrin is accumulated in tumours due to its interaction with protein. Cancer therapy with porphyrin as a carrier molecule is attracting attention. Porphyrin displays two functional sites termed β- and meso-positions. A correlation between the functional position on the porphyrin molecule and the ability to accumulate in cancer cells is observed in the present study. The accumulation of porphyrin derivatives was determined by measuring fluorescence intensity after incubation for 2 and 24 h. The accumulation of cancer cells depended on the position and length of functional groups. Estimated binding constants between porphyrin and bovine serum albumin suggest that the position of functional groups leads to changes in binding affinity and influences the accumulation of porphyrin derivatives in cancer cells.

We report a simple room-temperature synthesis route for increasing the reactivity of a TiO2 photocatalyst using a solution plasma process (SPP). Hydrogen radicals generated from the SPP chamber interact with the TiO2 photocatalyst feedstock, transforming its crystalline phase and introducing oxygen vacancy defects. In this work, we examined a pure anatase TiO2 as a model feedstock because of its photocatalytic attributes and well-characterized properties. After the SPP treatment, the pure anatase crystalline phase was transformed to an anatase/brookite heterocrystalline phase with oxygen vacancies. Furthermore, the SPP treatment promoted the absorption of both UV and visible light by TiO2. As a result, TiO2 treated by the SPP for 3 h showed a high gaseous photocatalytic performance (91.1%) for acetaldehyde degradation to CO2 compared with the activity of untreated TiO2 (51%). The SPP-treated TiO2 was also more active than nitrogen-doped TiO2 driven by visible light (66%). The overall photocatalytic perfor...

Platinum nanoparticle-supported boron-doped diamond powder (Pt/BDDP) was prepared and investigated as a durable polymer electrolyte fuel cell (PEFC) cathode catalyst. The use of the nanocapsule method enabled dense deposition of Pt nanoparticles (2–5 nm in size) on a boron-doped diamond (BDD) powder

We focused on a micro diamond (MD) particle with the highest thermal conductivity among existing materials and aimed to make a MD/copper composite material by electroplating. However, copper is naturally non-wetting with MD due to its chemical incompatibility, leading to weak interfacial bonding and high thermal resistance. We improved the wettability between MD and copper functionalized by the amino group on the MD using a photocatalytic reaction. The functionalization of the diamond surface by amino groups was achieved by treating the MDs in a 3-aminopropyltrimethoxysilane-containing solution. The amino group functionalized MD was dispersed in the electroplating bath, where copper was deposited on the MD. As a result, the composite material of amino group functionalized MD assisted by photocatalyst and copper improved their interfacial affinity and exhibited the high thermal conductivity of 595 W/m K.

Techniques for large-area pattern formation on polymeric substrates are important for fabricating a large variety of functional devices, such as flexible electronics, tunable optical devices, adhesives, and so on. The present study demonstrates a method for pattern formation on poly(dimethylsiloxane) that involves grafting methacrylate polymers through photo-initiated polymerization. The influence of substrate stiffness and monomers type on pattern formation was investigated. Firstly, the stiffness of the substrate was found to affect the topology of the patterns produced. The gap width of convex regions of the pattern was enlarged with decreasing stiffness. It was found that the gap width trended in a manner that was consistent with previous reports, but in this study, relatively large gap widths were observed compared with those from previous studies. Secondly, it was revealed that the solubility of the monomer in the poly(dimethylsiloxane) precursor was the dominant factor in determining whether or not pattern formation occurred. When using insoluble monomers (glycidyl methacrylate and benzyl methacrylate), characteristic patterns were observed. It is speculated that intermolecular attractive forces between the grafted polymers induce lateral aggregation on the substrate, resulting in buckling instability of the grafted polymer layer caused by a mismatch in the equilibrium between the grafted polymer layer and the substrate. Copyright © 2017 John Wiley & Sons, Ltd.

A boron-doped diamond (BDD) electrode with a large specific surface area was fabricated by formation of a hierarchical nanostructure. A BDD thin film was deposited on a silicon pillar array substrate fabricated using photolithography to obtain a BDD pillar array (BDD-PA). The BDD-PA was subjected to a two-step thermal treatment to form dense pores on the surface (P-BDD-PA). The P-BDD-PA was then treated by reactive ion etching (RIE) to form nanowhiskers on the surface (P-BDDW-PA). The combination of these structures (pillar array, pores and nanowhiskers) enabled enhanced double-layer capacitance (ca. 2800 μF cm − 2 ) based on the enlarged specific surface area without narrowing of the potential window (ca. 3 V) in an aqueous electrolyte. The combination of the two-step thermal treatment and RIE treatment should be an effective post-treatment method for enhancement of the capacitance of porous BDD materials consisting of micrometer-sized structures without significant increase of the time constant.

A liposome is a molecular assembly in the form of a vesicle comprised of a phospholipid bilayer. Liposomes can be used as molecular containers in various fields such as pharmaceutical, cosmetic, and food industries. It is difficult to maintain the original structure of liposomes in an aqueous medium. Phospholipids, which are components of liposomes, are susceptible to hydrolysis, which causes disruption of the liposomal structure and dysfunction of the molecular container. In this context, freeze-drying liposomes is a preferable method to improve the shelf life of liposomes. However, when freeze-drying liposomes, a lyoprotective agent is required to preserve their original structure. In this study, we investigate whether alkyl sulfobetaines (SBn, n: number of carbons in the alkyl chain, n = 1-18) can be used as lyoprotectants for 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes. The results indicated that the length of the alkyl chain of the SBn was an important factor to prevent liposome disruption during the freeze-drying and subsequent rehydration processes. The use of SBn with an alkyl chain of intermediate length (n = 6-10) could prevent liposome disruption and remarkably reduce the gel-to-liquid crystal phase transition temperature (Tm) of the freeze-dried liposomes. This indicates that these SBn could intercalate in the dried bilayer and reduce intermolecular interaction between DPPC in the bilayer. The Tm reduction of the freeze-dried liposomes should contribute to prevention of the gel-to-liquid phase transition of the liposomes during the rehydration process, which has been known to be a main cause of liposome disruption. We expect that the results from this study will provide an insight into the influence of zwitterionic additives on freeze-dried lipid bilayers and the lyoprotective effect, which should be useful in many biochemical and biomedical fields.

Herein, a conductive boron-doped nanodiamond (BDND) particle is prepared as an electrode material for an aqueous electric double-layer capacitor with high power and energy densities. The BDND is obtained by depositing a boron-doped diamond (BDD) on a nanodiamond particle substrate with a primary particle size of 4.7 nm via microwave plasma-assisted chemical vapor deposition, followed by heat treatment in air. The BDND comprises BDD and sp2 carbon components, and exhibits a conductivity above 1 S cm−1 and a specific surface area of 650 m2 g−1. Cyclic voltammetry measurements recorded in 1 M H2SO4 at a BDND electrode in a two-electrode system shows a capacitance of 15.1 F g−1 and a wide potential window (cell voltage) of 1.8 V, which is much larger than that obtained at an activated carbon electrode, i.e., 0.8 V. Furthermore, the cell voltage of the BDND electrode reaches 2.8 V when using saturated NaClO4 as electrolyte. The energy and power densities per unit weight of the BDND for charging–discharging in 1 M H2SO4 at the BDND electrode cell are 10 Wh kg−1 and 104 W kg−1, respectively, and the energy and power densities per unit volume of the BDND layer are 3–4 mWh cm−3 and 10 W cm−3, respectively. Therefore, the BDND is a promising candidate for the development of a compact aqueous EDLC device with high energy and power densities.

Titanium dioxide (TiO2) has been widely used as a catalyst material in different applications such as photocatalysis, solar cells, supercapacitor, and hydrogen production, due to its better chemical stability, high redox potential, wide band gap, and eco-friendly nature. In this work TiO2 thin films have been deposited onto both glass and silicon substrates by the atmospheric pressure plasma jet (APPJ) technique. The structure and morphological properties of TiO2 thin films are studied using different characterization techniques like X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and field emission scanning electron microscopy. XRD study reveals the bronze-phase of TiO2. The XPS study shows the presence of Ti, O, C, and N elements. The FE-SEM study shows the substrate surface is well covered with a nearly round shaped grain of different size. The optical study shows that all the deposited TiO2 thin films exhibit strong absorption in the ultraviolet region. The oleic acid photocatalytic decomposition study demonstrates that the water contact angle decreased from 80.22 to 27.20° under ultraviolet illumination using a TiO2 photocatalyst.

In this study, the validity of TiO2-based photocatalysts anti-algal effects was examined with Chlorella vulgaris. Cu-modified TiO2 (without N dopants) showed clear anti-algal effect under white LED light. N-doped TiO2 (both with and without Cu modification) and Cu-modified TiO2 (without N dopants) showed clear anti-algal effects when UV light was used together with white LED light. S-doped TiO2 had no anti-algal effects and even promoted the growth of algae. The degree of the anti-algal effect differed depending on the dopants, surface modifications, and irradiation light. Photocatalysts create several active spices during their photocatalytic processes. Of these, the effects of superoxide radical (O 2 ·− ) and hydrogen peroxide (H2O2) on algae growth were examined. Photocatalysts with high anti-algal effect produced hydrogen peroxides effectively, while there was no correlation between productivity of superoxide radical and anti-algal effects. Thus, the ability to produce hydrogen peroxide is a plausible factor for determining the efficiency of the anti-algal effect of a photocatalysts.

Electrolytic cells for electrochemical oxygen demand (ECOD) measurements based on total electrolytic decomposition at a boron-doped diamond (BDD) electrode were developed for rapid measurement of organic pollutants at low concentrations. Using improved electrolytic cells designed for efficient mass transfer, the ECOD for 10 μM potassium hydrogen phthalate (theoretical ECOD: 2.3 mg-O2 L-1) was determined in a relatively short electrolysis time. Thus, ECOD measurements using these cells would be useful for estimating organic water pollution in industrial waste and lake water.

Intermolecular interactions between lipid molecules are important when designing lipid bilayer interfaces, which have many biomedical applications such as in drug delivery vehicles and biosensors. Phosphatidylcholine, a naturally occurring lipid, is the most common lipid found in organisms. Its chemical structure has a negatively charged phosphate linkage, adjacent to an ester linkage in a glycerol moiety, and a positively charged choline group, placed at the terminus of the molecule. Recently, several types of synthetic lipids that have headgroups with the opposite charge to that of phosphatidylcholine have emerged; that is, a positively charged ammonium group is present adjacent to the ester linkage in their glycerol moiety and a negatively charged group is placed at their terminus. These types of lipids constitute a new class of soft material. The aim of this study was to determine how such lipids, with antiparallel arranged headgroup charge, interact with naturally occurring phosphatidylcholines. We synthesized 1,2-dipalmitoyl-sn-glycero-3-sulfobetaine (DPSB) to represent a reversed-head lipid; 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) was used to represent a naturally occurring phospholipid. The intermolecular interaction between these lipids was investigated using surface pressure-area (π-A) isotherms of the lipid monolayer at the air/water interface. We found that the extrapolated area and excess free energy of the mixed monolayer deviated negatively when compared with the ideal values from additivity. Moreover, differential scanning calorimetry of the lipid mixture in aqueous dispersion showed that the gel-to-liquid crystal transition temperature increased compared with that of each pure lipid composition. These results clearly indicate that DPSB preferably interacts with DPPC in the mixture. We believe that the attraction between the oppositely charged headgroups of these lipids reinforces the intermolecular interaction. Our results provide insight into the intermolecular interaction between phospholipids and reversed-head lipids, which may prove useful for the design of lipid-based materials in the future.

A coating was developed by controlling its glass transition temperature (Tg). This coating attained its highest Tg value in wet conditions (wet Tg) of higher than 100 °C, and maintained its adhesion on stainless steel even after immersion in boiling water. When this coating material was applied to a conventional two-component epoxy structural adhesive as a metallic primer, it improved the primer adhesion durability on the stainless steel sheet in water significantly, even if it was not chemically modified (without pretreatment). This indicated that a relative weak hydrogen bond between the hydroxyl group of the epoxy network and a surface hydroxyl group of the oxide layer of the stainless steel could be sufficient to prevent water penetration into the interface if the thermal mobility of the epoxy network is restrained. An investigation by X-ray photoelectron spectroscopy (XPS) indicated an interaction between a primer amino-group component and the metallic surface accompanied by proton transfer. However, the thermal mobility of the epoxy network could be the most important factor in its adhesion in wet conditions.

The surface of nanodiamond (ND) particles was modified with 1-octadecene via a simple thermal reaction to obtain octadecyl-modified ND. Fourier transform infrared spectroscopy and thermogravimetric analysis results indicated that octadecyl groups were successfully introduced onto the ND surface. The amount of the octadecyl groups on the ND surface was observed to increase with increasing reaction time and to eventually saturate. A bead-milling process, which enabled disaggregation of NDs in 1-octadecene, was observed to increase the amount of octadecyl groups adsorbed onto the ND surface. The estimated surface coverage was as high as 2.2 × 1014 molecules cm−2, which corresponds to submonolayer level. Dispersion tests revealed that the octadecyl-modified ND particles exhibit hydrophobic/lipophilic character, whereas the oxidized ND (before surface modification with 1-octadecene) exhibited good dispersibility in water. Particle size distribution analysis by dynamic light scattering revealed that the particle size of the octadecyl-modified ND in chloroform, a non-polar solvent, was ca. 20 nm. Thus, the present method should be useful for fabricating NDs that can be dispersed in non-polar organic solvents and should facilitate the expansion of the application fields of ND.

Primary challenges in electrochemical CO2 reduction lie with its product selectivity and competitive hydrogen evolution reaction (HER). Therefore, selective CO2 reduction with less hydrogen evolution or without any hydrogen evolution is very essential for industrial interests. In this study, we report a selective electrochemical CO2 reduction at a boron-doped diamond electrode modified with Cu nanoparticles in ionic liquid. In addition to the improved product selectivity, control of the competitive HER was also achieved in this work.