DNA damage induced via dissociative attachment by low-energy electrons (0 to 20 eV) is well studied in both gas and condensed phases. However, the reactivity of ultrashort-lived prehydrated ([Formula: see text]) with components a biologically relevant environment has not been fully explored date. The electron transfer processes [Formula: text] nucleobases G, A, C, T nucleosides/nucleotides were investigated using 7-ps pulse radiolysis coupled pump-probe transient absorption spectroscopy...

A series of photoactive triads have been synthesized and investigated in order to elucidate photoinduced electron transfer hole migration mechanism across nanosized, rigid helical foldamers. The are comprised a central oligoamide foldamer bridge with 9, 14, 18, 19, or 34 8-amino-2-quinolinecarboxylic acid repeat units, two chromophores, an N-terminal oligo(para-phenylenevinylene) donor C-terminal perylene bis-imide acceptor. Time-resolved fluorescence transient absorption spectroscopic...

Damage to DNA via dissociative electron attachment has been well-studied in both the gas and condensed phases; however, understanding this process bulk solution at a fundamental level is still challenge. Here, we use picosecond pulse of high energy beam generate electrons liquid diethylene glycol observe dynamics ribothymidine different stages relaxation. Our transient spectroscopic results reveal that quasi-free with near conduction band effectively attaches leading new absorbing species...

A cyclometalated iridium complex is reported where the core comprises naphthylpyridine as main ligand and ancillary 2,2′-bipyridine attached to a pyrene unit by short alkyl bridge. To obtain with satisfactory purity, it was necessary modify standard synthesis (direct reaction of chloro-bridged dimer) method harnessing an intermediate tetramethylheptanolate-based complex, which subjected acid-promoted removal subsequent complexation. The photophysical behavior bichromophoric model without...

Abstract Iodoperfluooralkylation of terminal alkenes and alkynes is effectively photo‐promoted by benzophenone 2 (BP) or the photoreducible copper(II) complex 1 . In particular, BP at mol% in methanol upon 365 nm irradiation with a low‐pressure mercury lamp (type TLC=thin layer chromatography, 6 W) results fast reaction excellent yields. Complex exhibited very similar reactivity, suggesting that reactions involving are likely to be governed photoactivation processes, rather than...

Integrating a matched organic chromophore and Ru(II) complex with optimized tridentate polypyridine ligands instils reversible electronic energy transfer giving an unusually long room temperature luminescence lifetime (42 μs) without compromising the emission quantum yield.

Abiotic aromatic oligoamide foldamers are shown to self-assemble in solution form a double helix, which can accommodate bichromophoric thread its central void. While reversible electronic energy transfer is instilled between chromophoric termini of the free, flexible as evidenced through delayed luminescence, upon rigidification rod chromophores mutually distanced and effectively decoupled. Consequently, display their individual photophysical characteristics. The observed...

In this work, the mechanism of dioxygen reduction catalysed by gold nanoparticles (AuNPs) two electron donors was investigated, i.e., sodium ascorbate and hydroethidine, focusing on potential ROS (reactive oxygen species) formation, such as O2˙- H2O2. According to our results, when AuNPs catalyse O2, are formed only intermediates surface nanoparticles, they unavoidably reduced water, AuNPs. Thus, statement production in presence often reported literature is excessive. The can catalyze...

Abstract The size‐tunable emission of luminescent quantum dots (QDs) makes them highly interesting for applications that range from bioimaging to optoelectronics. For the same applications, engineering their luminescence lifetime, in particular, making it longer, would be as important; however, no rational approach reach this goal is available date. We describe a strategy prolong lifetime QDs through electronic energy shuttling triplet excited state surface‐bound molecular chromophore. To...

Naphthalimide-based ‘Pourbaix sensors’ for redox potential and pH fluoresce with a lifetime of 8.5 ns while photoinduced electron transfer occurs on time scale 20 ps.

Abstract Time-resolved identification of surface-bound intermediates on metallic nanocatalysts is imperative to develop an accurate understanding the elementary steps CO 2 reduction. Direct observation initial electron transfer form •− radicals lacking due technical challenges. Here, we use picosecond pulse radiolysis generate • − via aqueous attachment and observe stabilization processes toward well-defined nanoscale sites. The time-resolved method combined with molecular simulations...

With breast cancer being one of the most widespread causes death for women, there is an unmet need its early detection. For this purpose, we propose a non-invasive approach based on X-ray scattering. We measured samples from 107 unique patients provided by Breast Cancer Now Tissue Biobank, with total dataset containing 2958 entries. Two different sample-to-detector distances, 2 and 16 cm, were used to access various structural biomarkers at distinct ranges momentum transfer values. The...

Structural biomarkers determined by X-ray scattering of the tissues can complement conventional diagnostics and provide a pathway for early detection diseases. In present study, mouse models were utilized to observe progress prostate cancer. We induced cancer in left lobe prostate, whilst right was uninoculated. The mice sacrificed at several time points (Days 2, 4, 7, 16 after inoculation), lobes analyzed using scattering. Control samples also collected from healthy same points. This...

Background/Objectives: With the number of detected breast cancer cases growing every year, there is a need to augment histopathological analysis with fast preliminary screening. We examine feasibility using X-ray diffraction measurements for this purpose; Methods: In work, we obtained more than 6,000 patterns from 211 patients and examined both standard custom-developed methods, including Fourier coefficient analysis, their interpretation. Various preprocessing steps machine-learning...

Reactivity towards low‐energy electrons (LEE) has been hypothesized as a cause of radio‐modifying properties for various molecules. LEE's transient nature, however, prevents the establishment clear links between initial processes at sub‐ps time scale and final products radiolysis. Here, such are explored compound RRx‐001 (1‐bromoacetyl‐3,3‐dinitroazetidine). Picosecond pulse radiolysis demonstrates high scavenging capacity molecule secondary quasi‐free solvated forming stable parent anions...

The design and synthesis of switchable molecular tweezers based on a luminescent terpy(Pt-salphen)2 (1; terpy=terpyridine) complex is reported. Upon metal coordination, the can switch from an open "W"-shaped conformation to closed "U"-shaped form that adapted for selective recognition cations. Closing by coordination (M=Zn(2+), Cu(2+), Pb(2+), Fe(2+), Hg(2+)) was monitored (1)H NMR and/or UV/Vis titrations. During titration, exclusive formation 1:1 [M(1)] observed, without appearance...

Abstract A prototype luminescent turn‐on probe for Cu + (and Ag ) is described, harnessing a selective binding site (log K ass =9.4 and 7.3 , respectively) based on the coordinating environment of bacterial metallo‐chaperone CusF, integrated with terbium‐ion‐signaling moiety. Cation–π interactions were shown to enhance tryptophan triplet population, which subsequently sensitized, microsecond timescale, long‐lived terbium emission, offering novel approach in bioinspired chemosensor design.

Reversible electronic energy transfer is used for sensing oxygen traces and results in very high sensitivity.

Localization of the photosensitizer conjugation site in amphiphilic block copolymers is shown to have a great impact on photodynamic therapy efficiency. To this end, an asymmetric multifunctional derivative azadipyrromethene boron difluoride chelate (aza-BODIPY) was synthesized and inserted at specific locations polypeptide-based rod-coil copolymers. A study photophysical properties vesicle nanocarriers, obtained by self-assembly these copolymers, as well vitro tests two cancer cell lines...

Background/Objectives: With the number of detected breast cancer cases growing every year, there is a need to augment histopathological analysis with fast preliminary screening. We examine feasibility using X-ray diffraction measurements for this purpose. Methods: In work, we obtained more than 6000 patterns from 211 patients and examined both standard custom-developed methods, including Fourier coefficient analysis, their interpretation. Various preprocessing steps machine learning...

We investigate experimentally induction mechanisms in a screw flow of gallium toroidal channel. The is nonstationary and operated spin-down regime: the channel (and fluid) are initially set into solid body rotation; as stopped fluid strong helical motion by diverters located inside In this study, we put particular emphasis on generated these motions, which expected to develop over entire range turbulent scales. apply an external magnetic field either perpendicular axis parallel it. At large...

The first direct measurements of effective magnetic diffusivity in turbulent flow electro-conductive fluids (the so-called beta-effect) under Reynolds number Rm >> 1 are reported. performed a nonstationary liquid sodium, generated closed toroidal channel. peak level the reached Re \approx 3 10^6, which corresponds to 30. metal was determined by measuring phase shift between induced and applied fields. maximal deviation from its basic (laminar) value reaches about 50% .