Highly fluorescent chameleon nanoparticles and polymer films: multicomponent organic systems that combine FRET and photochromic switching

We describe the preparation of highly efficient stimulus-responsive fluorescence color-tuning in self-assembled supramolecular scaffold systems. The systems consisted of a photochromic compound (BP-BTE) in combination with unique luminescent organic materials (CN-MBE, TPS-CNMBE, TPA-2CNMBE) that exhibited intense fluorescence in the solid state. The emission spectrum was tuned by introducing fluorescence resonance energy transfer and photochromic switching capabilities into the system. The materials were used to successfully demonstrate novel fluorescence patterns that were responsive to multiple stimuli, displayed reversible fluorescence switching, and provided a nondestructive readout of the fluorescence signal.     

Efficient gene delivery in differentiated human embryonic stem cells

Human embryonic stem (hES) cells are capable of differentiating into pluralistic cell types, however, spontaneous differentiation generally gives rise to a limited number of specific differentiated cell types and a large degree of cell heterogeneity. In an effort to increase the efficiency of specified hES cell differentiation, we performed a series of transient transfection of hES cells with EGFP expression vectors driven by different promoter systems, including human cellular polypeptide chain elongation factor 1 alpha (hEF1alpha), human cytomegalo-virus, and chicken beta-actin. All these promoters were found to lead reporter gene expression in undifferentiated hES cells, but very few drug-selectable transfectants were obtained and failed to maintain stable expression of the transgene with either chemical or electroporation methods. In an attempt to increase transfection efficiency and obtain stable transgene expression, differentiated hES cells expressing both mesodermal and ectodermal markers were derived using a defined medium. Differentiated hES cells were electroporated with a hEF1alpha promoter-driven EGFP or human noggin expression vector. Using RT-PCR, immunocytochemistry and fluorescence microscopy, the differentiated hES cells transfected with foreign genes were confirmed to retain stable gene and protein expression during prolonged culture. These results may provide a new tool for introducing exogenous genes readily into hES cells, thereby facilitating more directed differentiation into specific and homogenous cell populations.     

Mushroom-Derived Bioactive Molecules as Immunotherapeutic Agents: A Review

Mushrooms with enhanced medicinal properties focus on finding such compounds that could modulate the human body’s immune systems. Mushrooms have antimicrobial, antidiabetic, antiviral, hepatoprotective, antitumor, and immunomodulatory properties due to the presence of various bioactive components. β-glucans are the major constituent of the mushroom cell wall and play a significant role in their biological activity. This review described the techniques used in the extraction of the active ingredients from the mushroom. We highlighted the structure of the bioactive polysaccharides present in the mushrooms. Therapeutic applications of different mushrooms were also described. It is interesting to note that mushrooms have the potential sources of many bioactive products that can regulate immunity. Thus, the development of functional medicinal food based on the mushroom is vital for human welfare.     

Effect of Three Defatting Solvents on the Techno-Functional Properties of an Edible Insect (Gryllus bimaculatus) Protein Concentrate

Edible insects have received global attention as an alternative protein-rich food. However, their structural characteristics make them difficult to digest. To overcome this obstacle, we assessed the techno-functional properties of three protein concentrates from the cricket Gryllus bimaculatus. Freeze-dried G. bimaculatus powder was defatted using ethanol, hexene, or acetone as solvents, and the techno-functional properties (protein solubility, water and oil holding capacity, foaming properties, emulsion capacity, and gel formation) of the protein concentrates were determined. Freeze-dried G. bimaculatus powder comprised approximately 17.3% crude fat and 51.3% crude protein based on dry weight. Ethanol was the most effective solvent for reducing the fat content (from 17.30% to 0.73%) and increasing the protein content (from 51.3% to 62.5%) of the concentrate. Techno-functionality properties drastically differed according to the defatting solvent used and foaming properties were most affected. Thus, the techno-functional and whole properties must be considered for proper application of edible insects to achieve global food sustainability.     

Molecular Design Approach Managing Molecular Orbital Superposition for High Efficiency without Color Shift in Thermally Activated Delayed Fluorescent Organic Light-Emitting Diodes

Molecular design principles of thermally activated delayed fluorescent (TADF) emitters having a high quantum efficiency and a color tuning capability was investigated by synthesizing three TADF emitters with donors at different positions of a benzonitrile acceptor. The position rendering a large overlap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) enhances the quantum efficiency of the TADF emitter. Regarding the orbital overlap, donor attachments at 2- and 6-positions of the benzonitrile were more beneficial than 3- and 5-substitutions. Moreover, an additional attachment of a weak donor at the 4-position further increased the quantum efficiency without decreasing the emission energy. Therefore, the molecular design strategy of substituting strong donors at the positions allowing a large molecular orbital overlap and an extra weak donor is a good approach to achieve both high quantum efficiency and a slightly increased emission energy.     

Characterization of reused U–10Zr heel residue containing rare-earth elements through surface treatment

Journal of Radioanalytical and Nuclear Chemistry - U–Zr–RE heel residue was manufactured after fabricating U–Zr–RE fuel slugs by an injection casting method. In order to...