76-54-0Relevant articles and documents
Regulative peroxidase activity of DNA-linked hemin by graphene oxide for fluorescence DNA sensing
Wang, Quanbo,Xu, Nan,Lei, Jianping,Ju, Huangxian
, p. 6714 - 6717 (2014)
The inhibition effect of graphene oxide toward the peroxidase activity of DNA-linked hemin was identified and conveniently utilized in the design of a homogenous fluorescence strategy for DNA sensing with high sensitivity. This journal is the Partner Organisations 2014.
Metal-binding and redox properties of substituted linear and cyclic ATCUN motifs
Neupane, Kosh P.,Aldous, Amanda R.,Kritzer, Joshua A.
, p. 65 - 76 (2014)
The amino-terminal copper and nickel binding (ATCUN) motif is a short peptide sequence found in human serum albumin and other proteins. Synthetic ATCUN-metal complexes have been used to oxidatively cleave proteins and DNA, cross-link proteins, and damage cancer cells. The ATCUN motif consists of a tripeptide that coordinates Cu(II) and Ni(II) ions in a square planar geometry, anchored by chelation sites at the N-terminal amine, histidine imidazole and two backbone amides. Many studies have shown that the histidine is required for tight binding and square planar geometry. Previously, we showed that macrocyclization of the ATCUN motif can lead to high-affinity binding with altered metal ion selectivity and enhanced Cu(II)/Cu(III) redox cycling (Inorg. Chem. 2013, 52, 2729-2735). In this work, we synthesize and characterize several linear and cyclic ATCUN variants to explore how substitutions at the histidine alter the metal-binding and catalytic properties. UV-visible spectroscopy, EPR spectroscopy and mass spectrometry indicate that cyclization can promote the formation of ATCUN-like complexes even in the absence of imidazole. We also report several novel ATCUN-like complexes and quantify their redox properties. These findings further demonstrate the effects of conformational constraints on short, metal-binding peptides, and also provide novel redox-active metallopeptides suitable for testing as catalysts for stereoselective or regioselective oxidation reactions.
G-quadruplex DNAzyme as the turn on switch for fluorimetric detection of genetically modified organisms
Qiu, Bin,Zheng, Zhen-Zhu,Lu, Yu-Jing,Lin, Zhen-Yu,Wong, Kwok-Yin,Chen, Guo-Nan
, p. 1437 - 1439 (2011)
A novel fluorescent sensor for detection of genetically modified organisms was developed, and in the sensor G-quadruplex DNAzyme (G-quadruplex-hemin complex) was used as the turn on switch.
Pyrocatalytic oxidation-strong size-dependent poling effect on catalytic activity of pyroelectric BaTiO3nano- And microparticles
Braeutigam, Patrick,Buchheim, Johannes R.,Neumeister, Peter,Raufeisen, Sascha,Stelter, Michael
, p. 23464 - 23473 (2020/11/18)
Pyrocatalysis is an emerging advanced oxidation process for wastewater remediation with the potential for thermal energy harvesting and utilization. Although several studies explored the potential of new pyrocatalyst materials to degrade harmful organic water pollutants, the role of important material properties and electric poling procedures on the pyrocatalytic activity is still unclear. In this work, we investigate the interdependence between particle size, electric poling and pyrocatalytic activity of BaTiO3 powders with nominal particle sizes of 100, 200 and 500 nm by using the dichlorofluorescein redox assay. Depending on the particle size, the influence of surface area or phase composition on the pyrocatalytic activity predominates. Moreover, we demonstrate that poling of pyrocatalysts leads to a strong size-dependent increase of pyrocatalytic activity. This poling effect increases with particle size up to +247% and can be explained with size-dependent changes in phase composition and domain structure. Combining all results, the progression of the pyrocatalytic activity as a function of particle size was derived and a future strategy for maximizing the catalytic performance of pyrocatalysts was developed. This study greatly improves the understanding about the role of important material properties and electric poling on pyrocatalytic activity, thus enabling an effective catalyst design. With the help of highly active catalysts, the pyrocatalytic process can take the next step in its development into a new and energy-efficient advanced oxidation process for water remediation.
Phthalocyanine–Virus Nanofibers as Heterogeneous Catalysts for Continuous-Flow Photo-Oxidation Processes
Anaya-Plaza, Eduardo,Aljarilla, Ana,Beaune, Grégory,Nonappa,Timonen, Jaakko V. I.,de la Escosura, Andrés,Torres, Tomás,Kostiainen, Mauri A.
, (2019/08/16)
The generation of highly reactive oxygen species (ROS) at room temperature for application in organic synthesis and wastewater treatment represents a great challenge of the current chemical industry. In fact, the development of biodegradable scaffolds to support ROS-generating active sites is an important prerequisite for the production of environmentally benign catalysts. Herein, the electrostatic cocrystallization of a cationic phthalocyanine (Pc) and negatively charged tobacco mosaic virus (TMV) is described, together with the capacity of the resulting crystals to photogenerate ROS. To this end, a novel peripherally crowded zinc Pc (1) is synthesized. With 16 positive charges, this photosensitizer shows no aqueous aggregation, and is able to act as a molecular glue in the unidimensional assembly of TMV. A step-wise decrease of ionic strength in mixtures of both components results in exceptionally long fibers, constituted by hexagonally bundled viruses thoroughly characterized by electron and confocal microscopy. The fibers are able to produce ROS in a proof-of-concept microfluidic device, where they are immobilized and irradiated in several cycles, showing a resilient performance. The bottom-up approach also enables the light-triggered disassembly of fibers after use. This work represents an important example of a biohybrid material with projected application in light-mediated heterogeneous catalysis.
