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Two kinds of silver(I) coordination polymers consisting of the same chemical composition, [Ag(CF3SO3)(L)] [L is 2-methylidene-1,3-bis(nicotinoyloxy)propane], were synthesized and characterized by infrared (IR) and photoluminescence (PL) spectroscopy, elemental and thermal analyses, and single-crystal X-ray diffractometry; these are catena-poly[[(trifluoromethanesulfonato-κO)silver(I)]-μ-2-methylenepropane-1,3-diyl dinicotinate-κ2 N:N′], [Ag(CF3SO3)(C16H14N2O4)] n , and its chloroform monosolvate, {[Ag(CF3SO3)(C16H14N2O4)]·CHCl3} n . The X-ray crystallographic measurements revealed that the silver(I) compounds exhibit one-dimensional sinusoidal or helical molecular structures depending on the solvent used for crystallization. Self-assembly in a methanol/chloroform mixture produces the sinusoidal molecular strand, whereas recrystallization from acetonitrile medium affords a racemic mixture of the helical strands. These compounds display a fluorescence emission arising from both the ligand-centred transition and the ligand-to-metal charge transfer (LMCT) in the solid state under ambient conditions.

Living organisms compartmentalize their catalytic processes in membranes to increase reaction efficiency and selectivity. To mimic the organelles of eukaryotic cells, here we develop an efficient and safe method for in situ encapsulating enzymes in aqueous-core mesoporous silica nanocapsules. The key to achieving an in situ encapsulation was to restrict the sol-gel reaction selectively at the water/oil interface. This was realized by introducing an aminosilane to the silica precursors, which served as both catalyst and an amphiphilic anchor that electrostatically assembly with negatively charged hydrolyzed alkoxysilanes at the interface. The semi-permeable silica shell protected enzymes from external proteolytic attack, and preserved enzymatic activity by allowing the transport of reactants and products. Finally, the enzyme-carrying nanocapsules, as synthetic nano-organelles, were able to successfully perform cascade reactions when enveloped in a polymer vesicle, mimicking the hierarchically compartmentalized reactions of eukaryotic cells. This in situ encapsulation approach provides a versatile platform for the delivery of biomacromolecules.

Major research efforts have recently focused on the fabrication of supraparticles from primary nano/micro colloidal particles. A relatively new and key development in this field was surface-templated evaporation driven synthesis (STED), which is a method to synthesize supraparticles by drying droplets of colloidal dispersions on liquid repellent surfaces. This method permits various colloidal particles to be assembled into supraparticles. Specifically, the low contact line friction of the dispersion-containing droplets on liquid repellent surfaces promotes the assembly of primary colloidal particles at the end of evaporation, yielding supraparticles. The STED method is advantageous by enabling the synthesis of supraparticles of various functions, sizes, shapes, compositions, and morphologies. Here, we present an overview of the STED method for supraparticle syntheses, including the (i) fundamental principles of the method and (ii) strategies to tailor the characteristics of supraparticles.

The prolonged use of enzymes under oxidative stress is a major challenge in enabling effective enzymatic reaction pathways. Herein, we report a biomimetic antioxidant defensive strategy capable of providing adequate protection of enzymes against superoxide-mediated oxidation. Superoxide dismutase (SOD) and catalase (CAT) were chosen as scavengers and covalently encapsulated into silica nanoreactors, together with glucose dehydrogenase (GDH), which simultaneously should produce the coenzyme nicotinamide adenine dinucleotide (NADH, reduced form). By the enzymatic reactions of SOD and CAT, the interior of silica nanoreactors becomes a “ROS safe zone” to protect the glucose-dependent NADH production of coencapsulated GDH. We further combined this protected NADH-producing module with photocatalytic nanoparticles that enable the light-triggered oxidation of NADH back to NAD+ (oxidized form). In combination, these two modules allow interconversion between NAD+ and NADH by the addition of glucose or by light irradiation (LED lamp or sunlight). This protection and regeneration strategy is a versatile tool for enzyme applications for biological reactors, catalysis, or prototypes of artificial organelles or building blocks that contains fragile biomolecules and rely on the coenzyme NAD+/NADH.

We explored the physiological effects of inhaling basil essential oil (BEO) and/or linalool and identified odor-active aroma compounds in BEO using gas chromatography/mass spectrometry (GC–MS) and GC–olfactometry (GC–O). Linalool was identified as the major volatile compound in BEO. Three groups of rats were administered BEO and linalool via inhalation, while rats in the control group were not. Inhalation of BEO for 20 min only reduced the total weight gain (190.67 ± 2.52 g) and increased the forced swimming time (47.33 ± 14.84 s) compared with the control group (219.67 ± 2.08 g, 8.33 ± 5.13 s). Inhalation of BEO for 5 min (392 ± 21 beats/min) only reduced the pulse compared with the control group (420 ± 19 beats/min). Inhalation of linalool only reduced the weight of white adipose tissue (5.75 ± 0.61 g). The levels of stress-related hormones were not significantly different among the groups. The total cholesterol and triglyceride levels decreased after inhalation of BEO for 20 min (by more than −10% and −15%, respectively). Low-density lipoprotein cholesterol levels were lowered (by more than −10%) by the inhalation of BEO and linalool, regardless of the inhalation time. In particular, BEO inhalation for 20 min was associated with the lowest level of low-density lipoprotein cholesterol (53.94 ± 2.72 mg/dL). High-density lipoprotein cholesterol levels increased after inhalation of BEO (by more than +15%). The atherogenic index and cardiac risk factors were suppressed by BEO inhalation. Animals exposed to BEO and linalool had no significant differences in hepatotoxicity. These data suggest that the inhalation of BEO and linalool may ameliorate cardiovascular and lipid dysfunctions. These effects should be explored further for clinical applications.

Synergistic strategies by combining nanoreactors and prodrugs hold tremendous potential in anticancer treatment. However, precise death of target cancer cells remains a significant challenge due to the absence of an elaborate cancer targeting strategy. Here, a dual-targeting approach that combines the action of H2O2-producing folate receptor-targeted nanoreactors with a cyclooxygenase-2 (COX-2) targeted prodrug is reported. A folate-modified silica nanoreactor encapsulating glucose oxidase (GOX) is prepared to generate H2O2, which induces oxidative stress and allows the activation of the prodrug by targeted intracellular delivery. A novel prodrug bearing both COX-2 targeting Celecoxib and SN-38 anticancer agent with an H2O2-cleavable thioketal linker to activate the drug is presented. By dual-targeting, the generated H2O2 from GOX triggers the cleavage of a thioketal linker in the prodrug to produce the active form of the SN-38 anticancer drug in cancer cells inducing synergistic cell death. This dual-targeting strategy with a synergistic potency can aid in developing selective and effective anticancer therapeutics.

In this study, odor components were analyzed using gas chromatography/mass spectrometry (GC/MS) and solid-phase microextraction (SPME), and odor-active compounds (OACs) were identified using GC-olfactometry (GC-O). Among the volatile compounds identified through GC-O

This study analyzed taste and odor profiles in broccoli stems with different methods of thermal processing using electronic tongue and electronic nose. In electronic tongue analysis, umami and bitterness were obviously changed upon thermal processing, however, saltiness, sweetness, and sourness showed slight variations. Between raw and thermally processed broccolis, microwaved broccoli showed the highest changes of tastes based on raw broccoli, however, blanched broccoli showed similar tastes to raw broccoli compared with the others. In electronic nose analysis, a total of 21 volatiles in broccolis were analyzed. Sulfur-containing volatiles were changed via thermal steps, and the generation and reduction of sulfur-containing compounds have occurred (i.e. methnaethiol, 2,4,5-trimethylthiazole). In addition, some of the thermal steps (oven-heating, microwave heating, air-frying) have occurred Maillard reaction, and thus pyridine was generated. Therefore, this study can provide flavor data in broccoli, and contribute to further research for flavor characteristics in broccoli using electronic sensors.

The regeneration of enzymatic cofactors by cell-free synthetic modules is a key step towards producing a purely synthetic cell. Herein, we demonstrate the regeneration of the enzyme cofactor NAD+ by photo-oxidation of NADH under visible-light irradiation by using metal-free conjugated polymer nanoparticles. Encapsulation of the light-active nanoparticles in the lumen of polymeric vesicles produced a fully organic module able to regenerate NAD+ in an enzyme-free system. The polymer compartment conferred physical and chemical autonomy to the module, allowing the regeneration of NAD+ to occur efficiently, even in harsh chemical environments. Moreover, we show that regeneration of NAD+ by the photocatalyst nanoparticles can oxidize a model substrate, in conjunction with the enzyme glycerol dehydrogenase. To ensure the longevity of the enzyme, we immobilized it within a protective silica matrix; this yielded enzymatic silica nanoparticles with enhanced long-term performance and compatibility with the NAD+ -regeneration system.

The purpose of this study was to investigate sensory characteristics in radishes, processed through different methods, using chemosensory-assisted instruments. For electronic tongue (E-tongue) analysis, freeze-dried radish was high in the sensor values of sourness, umami, and sweetness, however, the saltiness was the lowest. In particular, the sensor values of taste freeze-dried radish have changed more than that of thermally processed radishes. Unlike the results of E-tongue, volatiles of freeze-dried radish have changed less than that of thermally processed radishes. In detail, amounts of sulfur-containing compound (thiophene) in freeze-dried radish were relatively higher than thermally processed radishes by an electronic nose. For gas chromatography-mass spectrometry and GC-olfactometry, the amount of sulfur-containing compounds in freeze-dried radish were also relatively higher than thermally processed radishes, and odor active compounds were also high in freeze-dried radish.

The development of enzyme modules by coupling several enzymes in confinement is of paramount importance to artificial biological reaction systems for efficient enzymatic reactions. Silica nanocapsules are ideal candidates for loading enzymes. Aqueous core silica nanocapsules have relatively been rarely reported due to the crux of difficulty in forming dense silica shells by interfacial sol-gel reactions. Herein we suggest a one-step synthesis of hollow silica nanocapsules with an aqueous core containing enzymes via a template-free and interfacial condensation method for developing enzyme modules with coupled enzymatic reactions. As a proof-of-concept, we developed enzyme modules for three useful purposes by encapsulating a couple of enzymes: (i) development of a miniature glucose sensor, (ii) protection of living cells, and (iii) regeneration of nicotinamide adenine dinucleotides (NADs). By the modulation of enzymes using silica nanocapsules, more efficient coupled reactions, separation of enzymatic reactions from surroundings, and easy handling of several enzymes by using a single module could be achieved. Therefore, our silica nanocapsules for enzyme modules can be promoted as general platforms for developing artificial nanoreactors. This journal is

The versatile design of stimuli-responsive microparticles embedding valuable biomolecules has great potential in a variety of engineering fields, such as sensors, actuators, drug delivery, and catalysis. Here, results are reported on thermoresponsive core–gap–shell (TCGS) microcapsules made of poly(N-isopropylacrylamide) (PNIPAm), which encapsulate hydrophilic payloads in a simple and stable manner. These are realized by a one-step microfluidic approach using the phase separation of a supersaturated aqueous solution of NIPAm. Various designs of the microcapsules are achieved by individual control of the swelling or by incorporating pH-responsive comonomers of the inner core and outer shell. The gap, i.e., the space between the inner core and outer shell, can be loaded with cargo-like nanoparticles. The outer shell can serve as a stimuli-responsive gateway for the transport of smaller molecules from the external solution. It is shown that the TCGS microcapsules are suitable as temperature controllable glucose sensors and hold promise in the design of controllable enzymatic reactions. The proposed platform provides an avenue for developing a new-generation of microparticles for diverse and efficient engineering applications.

Liposomes with embedded magnetic nanoparticles (magnetoliposomes; MLs) are promising nano-platforms for various biomedical applications. The magnetic behavior of MLs depends on the size of embedded magnetic nanoparticles (MNPs); in general, larger MNPs are more advantageous (e.g. increased magnetic signals). However, the insertion of large MNPs into liposome bilayers is constrained by the thickness of the membrane (∼3.4 nm); thus, the incorporation of larger magnetic nanoparticles (>3.4 nm) into liposomes is a major challenge. We developed a solvent-guided approach for the simple and efficient insertion of large MNPs (6 nm or 15 nm) into the liposomal bilayer. MLs with 6 nm MNPs were used for the magnetic field-guided separation of cancer cells by targeting to human epidermal receptor 2 and folate receptor. We also evaluated the nuclear delivery of oligonucleotides by MLs with a cationic lipid formula. The MLs are expected to be versatile nano-platforms for biomedical applications (e.g. disease diagnosis, therapeutics and cell tracking).

Physical separation of reactions by interactive multicompartments in biological cells is an attractive motif to design efficient microreactors that create biomimetic cascade reactions. We present an aqueous compartment with three different subcompartments that comprise of silica nanoreactors with encapsulated enzymes, namely, β-glucosidase, glucose oxidase, and peroxidase, providing a model cascade reaction in confinement. The encapsulated enzymes retain their activity as the substrate can reach the active site and the silica shell further protects the enzymes from external stresses, such as heat and proteolytic degradation. We demonstrate the biomimetic cascade reaction in between the compartments ("organelles") inside of an additional microconfinement (water-in-oil emulsion). This strategy will allow us to design efficient multicompartmentalized reactors for further biological and organic reactions.

In situ generation of anticancer agents at the place of the disease is a new paradigm for cancer therapy. The production of highly potent drugs by nanoreactors through a facile synthesis pathway is demanded. We report an oncolytic nanoreactor platform loaded with the enzyme glucose oxidase (GOX) to produce hydrogen peroxide. For the first time, we realized a core-shell structure with encapsulated GOX under mild synthetic conditions, which ensured high remaining activity of GOX inside of the nanoreactor. Moreover, the nanoreactor protected the loaded GOX from proteolysis and contributed to increased thermal stability of the enzyme. The nanoreactors were effectively taken up into different cancer cells, in which they produced hydrogen peroxide by consuming intracellular glucose and oxygen, thereby leading to effective death of the cancer cells. In summary, our robust nanoreactors are a promising platform for effective anticancer therapy and sustained enzyme utilization.

In order to improve the cell seeding efficiency and cell compatibility inside porous tissue scaffolds, a method of fibrin gel-mediated cell encapsulation inside the scaffold was optimized. Disc-type poly(d,l-glycolic-co-lactic acid) (PLGA) scaffolds without a dense surface skin layer were fabricated using an established solvent casting and particulate leaching method as a model porous scaffold, which showed high porosity ranging from 90 ± 2% to 96 ± 2%. The thrombin and fibrinogen concentration as precursors of fibrin gel was varied to control the gelation kinetics as measured by rheology analysis, and optimized conditions were developed for a uniform fibrin gel formation with the target cells inside the porous PLGA scaffold. The fibroblast cell seeding accompanied by a uniform fibrin gel formation at an optimized gelation condition inside the PLGA scaffold resulted in an increase in cell seeding efficiency, a better cell proliferation, and an increase in final cell density inside the scaffold. Scanning electron microscopy images revealed that cells were better spread and grown by fibrin gel encapsulation inside scaffold compared with the case of bare PLGA scaffold. Copyright © 2016 John Wiley & Sons, Ltd.

The regeneration of enzymatic cofactors by cell-free synthetic modules is a key step towards producing a purely synthetic cell. Herein, we demonstrate the regeneration of the enzyme cofactor NAD

Nanoparticle clusters (NPCs) have attracted significant interest owing to their unique characteristics arising from their collective individual properties. Nonetheless, the construction of NPCs in a structurally well-defined and size-controllable manner remains a challenge. Here we demonstrate a strategy to construct size-controlled NPCs using the DNA-binding zinc finger (ZnF) protein. Biotinylated ZnF was conjugated to DNA templates with different lengths, followed by incubation with neutravidin-conjugated nanoparticles. The sequence specificity of ZnF and programmable DNA templates enabled a size-controlled construction of NPCs, resulting in a homogeneous size distribution. We demonstrated the utility of magnetic NPCs by showing a three-fold increase in the spin-spin relaxivity in MRI compared with Feridex. Furthermore, folate-conjugated magnetic NPCs exhibited a specific targeting ability for HeLa cells. The present approach can be applicable to other nanoparticles, finding wide applications in many areas such as disease diagnosis, imaging, and delivery of drugs and genes.

Capturing tumor cells has attracted the attention because such cells can be used for diagnosing the occurrence and progression of cancers. Here we present a simple and efficient capturing of tumor cells using anti-EGFR antibody-conjugated magnetic nanoparticles. EGFR is a well-established epithelial cancer-specific marker that is over-expressed in many types of tumor cells. The conjugation of an anti-EGFR antibody with magnetic nanoparticles through a PEG-linker was shown to be highly efficient for preventing the non-specific binding of cells and improving the stability of the resulting nanoparticles even at a high salt concentration. The use of EGFR-targetable nanoparticles resulted in about 57% capture efficiency in 20 min for two cancer cell lines, PC9 (lung cancer) and HeLa (cervical cancer). The survival rate of the captured cells was approximately 85%, and most of the cells were retrievable, providing options for a further analysis of captured cells such as a mutational investigation of EGFR-related cancers. The present approach can be used for capturing circulating tumor cells (CTCs) expressing EGFR and the subsequent diagnostic analysis of the captured cells.

Nanohybrids of nylon 6 and nano-titania (TiO 2 ) were prepared by melt compounding with a twin-screwextruder to investigate antibacterial activity. It was confirmed by field emission scanning electron microscopy (FE-SEM), energy dispersive spectrometry (EDS), and X-ray diffraction (XRD) that nano-TiO 2 was successfully dispersedin the nylon 6 matrix at the level of individual particles. After immersion in an aqueous solution of AgNO 3 at 100 ppmAg ion concentration, silver was introduced to the nanohybrids through photocatalytic reduction by nano-TiO 2 underUV (254 nm) irradiation. With increasing nano-TiO 2 content, the nanohybrids with silver photodeposited on the nano-TiO 2 . The nylon 6/TiO 2 -Ag nanohybrids exhibited strong antimicrobial activity against Klebsiella pneumoniae andStaphylococcus aureus in measurements with the shaking flask method. Keywords: nylon 6, nano-TiO 2 , photodeposition by UV irradition, silver, antibacterial activity 1. 서론 섬유제품에 항균성을 부여하는 방법은 여러 가지가 있는데, 항균성 염료[1]나 화학 항균제를 사용하는 경우도 있지만 최근 들어서는 인체에 유해할 수 있는 여러 종류의 화학 항균제 대신 인체 독성이 낮은 무기 소재를 복합하여플라스틱 또는 섬유제품에 항균성을 부여하는 것이 대체기술로 선호되고 있는 추세이다[2]. 고분자를 기질로 하는나노복합은 항균성을 비롯한 복합기능성을 부여하는 목적의 새로운 분야로서 개척되고 있다[3,4].그 중에서도 자외선이 조사되면 우수한 광촉매 특성을발휘하는 나노 이산화티타늄(titanium dioxide, TiO

Exon 2 deletion in aminoacyl tRNA synthetase complex-interacting multifunctional protein 2 (AIMP2) has been suggested to be associated with the progression of various cancers such as lung and ovarian cancers. However, few studies have been conducted regarding detection and relevance of exon 2-deleted AIMP2 (AIMP2-DX2) mutation to a specific cancer. Here, we demonstrate the rapid and simple detection of the AIMP2-DX2 mutation by molecular beacons and its relation to lung cancer. Real-time PCR with molecular beacons allowed a sensitive detection of the AIMP2-DX2 mutation as low as 0.3 pg initial template. Dual-conjugated liposomes with folate and molecular beacon enabled fluorescence imaging of cancer cells harboring the AIMP2-DX2 mutation with high resolution. Association of the AIMP2-DX2 mutation with lung cancer was shown by analyzing tissue samples from lung cancer patients using real-time PCR. Approximately, 60% of lung cancer patients harbored the AIMP2-DX2 mutation, which implies a potential of the AIMP2-DX2 mutation as a prognostic biomarker for lung cancer. Molecular beacon-based approaches will find applications in the simple and rapid detection of mutations on nucleotides for diagnosing and monitoring the progression of relevant cancer.