EPR Study of KO2 as a Source of Superoxide and •BMPO-OH/OOH Radical That Cleaves Plasmid DNA and Detects Radical Interaction with H2S and Se-Derivatives

Superoxide radical anion (O2•−) and its derivatives regulate numerous physiological and pathological processes, which are extensively studied. The aim of our work was to utilize KO2 as a source of O2•− and the electron paramagnetic resonance (EPR) spin trapping 5-tert-butoxycarbonyl-5-methyl-1-pyrroline N-oxide (BMPO) technique for the preparation of •BMPO-OOH and/or •BMPO-OH radicals in water solution without DMSO. The method distinguishes the interactions of various compounds with •BMPO-OOH and/or •BMPO-OH radicals over time. Here, we show that the addition of a buffered BMPO-HCl mixture to powdered KO2 formed relatively stable •BMPO-OOH and •BMPO-OH radicals and H2O2, where the •BMPO-OOH/OH ratio depended on the pH. At a final pH of ~6.5–8.0, the concentration of •BMPO-OOH radicals was ≥20 times higher than that of •BMPO-OH, whereas at pH 9.0–10.0, the •BMPO-OH radicals prevailed. The •BMPO-OOH/OH radicals effectively cleaved the plasmid DNA. H2S decreased the concentration of •BMPO-OOH/OH radicals, whereas the selenium derivatives 1-methyl-4-(3-(phenylselanyl) propyl) piperazine and 1-methyl-4-(4-(phenylselanyl) butyl) piperazine increased the proportion of •BMPO-OH over the •BMPO-OOH radicals. In conclusion, the presented approach of using KO2 as a source of O2•−/H2O2 and EPR spin trap BMPO for the preparation of •BMPO-OOH/OH radicals in a physiological solution could be useful to study the biological effects of radicals and their interactions with compounds.

From Analytical Аnthropology to Generative Anthropology

This article discusses the role of the technical in V.A. Podoroga's project of studying the literature worlds as archives of human experience. On the level of content, among many other components of these worlds he distinguished working and non-working machines, “gizmos” and various optical devices, including the mechanic eye, camera, mounting, etc. Formally, the action of these machines can be assessed as alienation, though in the context of modern media studies and exploration of the perspectives of anthropology, they can also be described as a problematic contact zone between the human and non-human, with a bias towards breaking the already historically disrupted bodily-affective interaction with the “outside”. Studies of Andrei Platonov's show the most radical interaction with the technical, in this case causing dissimilation of the human. However, even for this “inhuman” material, Podoroga chooses a form of human-measured approximation and distancing, which allows defending the position of an active researcher, observer, anthropologist. His efforts produce a kind of reconstruction, which at a certain time distance reveals the “seams”, “folds”, “cuts”, “plexuses”, “gaps” that formed at once the experience of the body and experience of writing. This is how the components of literature worlds are extracted, and from them “a picture of the universe can be deduced”. Although an external position to technics is considered to be the only guarantee of the human, even if it is strange, symptomatic, seizure-like, a different understanding of the technical is possible. Without claiming that a “machine” can assemble components in the absence of the observer's (reader's) comprehension ability, it seems nevertheless possible to relate the technical to more general principles: the methods of dispersion and gathering that form the form, the principles of intervalization and binding the heterogeneous, and most importantly, the principle of generating conditions for detecting an event. Then it will be necessary to clarify the relationship between techne and literature in the broader sense of poiesis, in the process of which elements can be formed from the indivisible “compressed”.

A Zr-cluster based thermostable, self-healing and adaptive metallogel with chromogenic properties responds to multiple stimuli with reversible radical interaction

A Zr-cluster based metallogel is synthesized via an unusual one-pot solvothermal method. The gel displays outstanding mechanical and stimuli-responsive properties, which could be used as soft electrochromic devices.

Anion–π and anion–π-radical interactions in bis(triphenylphosphonium)-naphthalene diimide salts

Anion–π-radical interaction plays a key role in photophysical and magnetic properties.