A Photo-Responsive Organogel Based on Pyrene-Substituted Acylhydrazone Derivative

A new simple pyrene-substituted acylhydrazone derivative, 4-(3,4-dioctyloxy) phenyl-1-pyrene acylhydrazone (PAH-8), was designed and synthesized. The PAH-8 can form thermo-reversible organogel in DMSO, and shows gelation-induced enhanced fluorescence emission. Xerogel exhibits ribbon-like fibrous aggregates with widths of 0.5-1 μm. The PAH-8 organogel indicates photo-responsive behaviors due to the trans-cis isomerizations of -C=N- bond upon exposure to visible or UV light. Upon visible light irradiation, the partial trans-cis isomerization of the -C=N- bond causes the fiber morphology to disappear, resulting in gel-sol transition, whereas the PAH-8 organogel exhibits few photoisomerizations from trans to cis transition without breakage of the gel state upon UV light irradiation.     

New designed DNA light switch Ruthenium complexes as DNA photocleavers and Topoisomerase I inhibitors

Two ruthenium complexes containing a new ligand phipz (phipz = 2‐(1,10‐phenanthroline)‐1H‐imidazo[4,5‐b]phenazine) were designed and synthesized. These complexes were found to inhibit the DNA supercoiled relaxation mediated by topoisomerase I (topo I), cleave DNA under irradiation and bind to calf thymus DNA through intercalative mode. Furthermore, complex 2 shows higher photocleavage activity, topo I inhibition activity and DNA affinity than complex 1 . Additionally, introduction of phenazine unit may be the reason that two complexes exhibit DNA ‘light switch’ behavior. The present work shows that two complexes might be potential as new DNA ‘light switches’, DNA photocleavers and topo I inhibitors.     

Enhanced optical transmission through an array of compound unit with multiple concentric or eccentric annular apertures

In this paper, transmission properties through an array of compound unit with multiple concentric or eccentric annular apertures are numerically studied. It is demonstrated that the transmission of the compound structure is not a simple superposition of that of each annular aperture array but exhibit substantial changes in both the position and intensity of resonant peaks. It is also found that the gap plasmon resonance exhibit split peaks when the symmetry is broken, which can be well explained from the view of charge oscillation. These properties provide a method to achieve enhanced transmission in multi-frequencies simultaneously and are of significant applicable value to the design of tunable optical devices.     

Development and testing of a Frisch-Grid Ionization Chamber for the measurement of low activity of alpha-particle emitters

Journal of Radioanalytical and Nuclear Chemistry - A Frisch-grid Ionization Chamber (FGIC) for the measurement of low activity of alpha-particle emitters has been built. The design and performance...     

Spatial variability and radiation assessment of the radionuclides in soils and sediments around a uranium tailings reservoir,south of China

Journal of Radioanalytical and Nuclear Chemistry - The concentrations of 238U, 226Ra, 232Th and 40K and gross α, β were measured in soils and sediments around a uranium tailings reservoir...     

Facile Synthesis of Mg2+‐Doped Carbon Dots as Novel Biomaterial Inducing Cell Osteoblastic Differentiation

Carbon dots (CDs), as an emerging fluorescent nanomaterial with low toxicity, has been widely applied in various bio‐related fields. However, investigations on their capabilities in guiding osteogenic differentiation are rarely seen, which has great significance in osteoporosis therapy and bone regeneration. Herein, for the first time, a new kind of Mg²⁺‐doped CDs is facilely synthesized through a one‐step hydrothermal method from metal gluconate salts. The CDs can serve as nanocarrier of Mg²⁺ ions entering into cells, and the bioessential metal ions subsequently stimulate osteoblastic differentiation by improving alkaline phosphatase (ALP) activity and upregulation related mRNA expression. Noteworthy, the raw material has almost negligible performance on osteoblastic differentiation compared to Mg‐CDs, which is due to the ultrasmall sizes of CDs and the efficient uptake by cells. Moreover, benefitting from the fluorescence properties, Mg‐CDs can also be applied as cell labeling agents. This work proposes a new strategy to synthesize multifunctional metal ion‐doped CDs, which might had great potential in serving as promising nanodrugs for bone loss therapy.