Induction of Mutation by Synchrotron-light Irradiation in Chinese Lantern (Physalis alkekengi L. var. franchetii Makino) with Purplish Brown-colored Persistent Calyx

Photodegradation of textile dyes in the presence of an aqueous suspension of semiconductor oxides has been of growing interest. Although this method of destruction of dyes is efficient, the main obstacle of applying this technique in the industry is the time and cost involving separation of oxides from an aqueous suspension. In this research, an attempted was made to develop ZnO films on a glass substrate by simple immobilization method for the adsorption and photodegradation of a typical dye, Remazol Red R (RRR) from aqueous solution. Adsorption and photodegradation of RRR were performed in the presence of glass supported ZnO film. Photodegradation of the dye was carried out by varying different parameters such as the catalyst dosage, initial concentrations of RRR, and light sources. The percentage of adsorption as well as photodegradation increased with the amount of ZnO, reaches a maximum and then decreased. Maximum degradation has been found under solar light irradiation as compared to UV-light irradiation. Removal efficiency was also found to be influenced by the pre-sonication of ZnO suspension.

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Tyrosine-Selective Bioconjugation with Iminoxyl Radicals

10.26434/chemrxiv.12278717 ◽

2020 ◽

Author(s):

Katsuya Maruyama ◽

Takashi Ishiyama ◽

Yohei Seki ◽

Kounosuke Oisaki ◽

Motomu Kanai

Keyword(s):

Reaction Time ◽

Steric Hindrance ◽

Room Temperature ◽

Water Soluble ◽

Light Irradiation ◽

Sodium Ascorbate ◽

Iminoxyl Radical ◽

Short Reaction Time ◽

Modified Peptides ◽

The Stability

A novel Tyr-selective protein bioconjugation using the water-soluble persistent iminoxyl radical is described. The conjugation proceeded with high Tyr-selectivity and short reaction time under biocompatible conditions (room temperature in buffered media under air). The stability of the conjugates was tunable depending on the steric hindrance of iminoxyl. The presence of sodium ascorbate and/or light irradiation promoted traceless deconjugation, restoring the native Tyr structure. The method is applied to the synthesis of a protein-dye conjugate and further derivatization to azobenzene-modified peptides.

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Cu Doped TiO2: Visible Light Assisted Photocatalytic Antimicrobial Activity and High Temperature Anatase Stability

10.26434/chemrxiv.7159733.v1 ◽

2018 ◽

Cited By ~ 2

Author(s):

Snehamol Mathew ◽

Priyanka Ganguly ◽

Stephen Rhatigan ◽

Vignesh Kumaravel ◽

Ciara Byrne ◽

...

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Density Functional ◽

Anatase Phase ◽

Sol Gel ◽

Chemical Properties ◽

Light Irradiation ◽

Health Concern ◽

Bacterial Inactivation ◽

X Ray

Indoor surface contamination by microbes is a major public health concern. A damp environment is one potential sources for microbe proliferation. Smart photocatalytic coatings on building surfaces using semiconductors like titania (TiO2) can effectively curb this growing threat. Metal-doped titania in anatase phase has been proved as a promising candidate for energy and environmental applications. In this present work, the antimicrobial efficacy of copper (Cu) doped TiO2 (Cu-TiO2) was evaluated against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive) under visible light irradiation. Doping of a minute fraction of Cu (0.5 mol %) in TiO2 was carried out via sol-gel technique. Cu-TiO2 further calcined at various temperatures (in the range of 500 °C – 700 °C) to evaluate the thermal stability of TiO2 anatase phase. The physico-chemical properties of the samples were characterised through X-ray diffraction (XRD), Raman spectroscopy, X-ray photo-electron spectroscopy (XPS) and UV-visible spectroscopy techniques. XRD results revealed that the anatase phase of TiO2 was maintained well, up to 650 °C, by the Cu dopant. UV-DRS results suggested that the visible light absorption property of Cu-TiO2 was enhanced and the band gap is reduced to 2.8 eV. Density functional theory (DFT) studies emphasises the introduction of Cu+ and Cu2+ ions by replacing Ti4+ ions in the TiO2 lattice, creating oxygen vacancies. These further promoted the photocatalytic efficiency. A significantly high bacterial inactivation (99.9%) was attained in 30 mins of visible light irradiation by Cu-TiO2.

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Photo-Fenton Degradation of RhB over Nano-fibre Iron Oxides Interacted Montmorillonite under Visible Light Irradiation

CHINESE JOURNAL OF CATALYSIS (CHINESE VERSION) ◽

10.3724/sp.j.1088.2012.20756 ◽

2013 ◽

Vol 33 (10) ◽

pp. 1736-1741

Author(s):

Shilong ZHANG ◽

Xiaoming HU ◽

Xiaowei WANG ◽

Shijing LIANG ◽

Ling WU

Keyword(s):

Visible Light ◽

Iron Oxides ◽

Visible Light Irradiation ◽

Light Irradiation

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Development of Synchrotron Footprinting at NSLS and NSLS-II

Protein and Peptide Letters ◽

10.2174/0929866526666181128125125 ◽

2019 ◽

Vol 26 (1) ◽

pp. 55-60 ◽

Cited By ~ 1

Author(s):

Jen Bohon

Keyword(s):

Solvent Accessibility ◽

Biological Systems ◽

In Vivo Studies ◽

Aqueous Samples ◽

Biological Mechanisms ◽

Macromolecular Assembly ◽

Structure And Dynamics ◽

Synchrotron Light ◽

Ideal Technique

Background: First developed in the 1990’s at the National Synchrotron Light Source, xray synchrotron footprinting is an ideal technique for the analysis of solution-state structure and dynamics of macromolecules. Hydroxyl radicals generated in aqueous samples by intense x-ray beams serve as fine probes of solvent accessibility, rapidly and irreversibly reacting with solvent exposed residues to provide a “snapshot” of the sample state at the time of exposure. Over the last few decades, improvements in instrumentation to expand the technology have continuously pushed the boundaries of biological systems that can be studied using the technique. Conclusion: Dedicated synchrotron beamlines provide important resources for examining fundamental biological mechanisms of folding, ligand binding, catalysis, transcription, translation, and macromolecular assembly. The legacy of synchrotron footprinting at NSLS has led to significant improvement in our understanding of many biological systems, from identifying key structural components in enzymes and transporters to in vivo studies of ribosome assembly. This work continues at the XFP (17-BM) beamline at NSLS-II and facilities at ALS, which are currently accepting proposals for use.

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