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In this article, 3,4-dihydroybenzylidenehydrazine is synthesized for the first time, and its properties as a dopamine analogue for polymerization are investigated. Using an oxidative polymerization reaction, the reaction mechanism as well as the coating ability of the new polymer is determined and compared to that of polydopamine. The polymerization reactions were performed in a mixture of methanol–water with NaIO4 as an oxidation reagent. The polymer was used as a coating on both glass surfaces with a thickness of ∼5 nm as determined by AFM, as well as on TiO2 nanoparticles. For the latter, SEM/TEM and the pH-dependent variation of zeta potential were measured. As a free polymer, poly-3,4-dihydroxybenzylidenhydrazine was investigated by UV-Vis, ss-NMR, and FTIR, and a variety of monomeric units were found in the polymer matrix. The solubility in methanol or DMSO of the monomer and the slight solubility of the polymer allowed us to study the fluorescence and cyclic voltammetry properties for both the monomer and polymer.

Kynurenic acid (KA), a key metabolite of tryptophan (TRP) via the kynurenine pathway, plays a significant role in various physiological and pathological conditions, including neurodegenerative diseases, depression, and schizophrenia. This study aims to develop a flexible and sensitive electrochemical sensor platform for the direct detection of KA in biological fluids. Custom carbon-based electrodes were fabricated using specialized inks and a flexible plastic substrate, followed by functionalization with a composite film of gold nanoparticles, graphene oxide (GO), and polyethyleneimine (PEI). The GO was electrochemically reduced to enhance conductivity and sensitivity for the target analyte. The sensor platform was characterized using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and atomic force microscopy (AFM). An optimized differential pulse voltammetry (DPV) method was employed for KA detection. The developed sensor demonstrated a detection limit of 0.3 nM and was effective across a concentration range of 1 nM to 500 µM. These findings highlight the potential of this electrochemical sensor as a reliable, rapid, and cost-effective tool for KA detection in various biological samples, offering significant advantages over traditional methods in terms of sensitivity and simplicity. [ABSTRACT FROM AUTHOR]

This study focuses on addressing the challenges associated with doxorubicin (DOX), an anthracycline chemotherapeutic widely used in cancer treatment. Despite its efficacy, DOX is linked to severe side effects that limit its clinical applications. Novel pharmaceutical formulations aim to mitigate these issues, providing better safety profiles. The development of these formulations requires analytical methods that can accurately and quickly quantify DOX. A cost-effective and portable electrochemical sensor for DOX detection was developed utilizing in-house printed carbon electrodes decorated with gold nanoparticles. DOX was detected using differential pulse voltammetry. The sensor demonstrated an accurate quantification of DOX from novel pharmaceutical formulations and serum, presenting a dynamic range of 1 to 500 μg/mL and a low detection limit of 0.3 μg/mL. The method, successfully applied to characterize DOX-loaded nanosomes, offers a valuable alternative in the early stages of formulation development, reducing costs and saving time, while maintaining accuracy. [ABSTRACT FROM AUTHOR]

This paper presents the activity level of total organically bound tritium (OBT) in different plant species, e.g., grains (wheat, corn), trees (apple, fir), and vines, and different organs of the plants (buds, leaves, fruits, straw, and branches) surrounding the Experimental Pilot Plant for Tritium and Deuterium Separation during the growing seasons of 2020 and 2021, The influence of environmental factors over OBT in the studied plant species is established by measurements of the tritium activity level in air and precipitations and their influence over tissue-free water tritium activity. [ABSTRACT FROM AUTHOR]

The electrolysis process is essential in the water detritiation subsystem using the combined electrolytic catalytic exchange process. A special experimental program was designed to characterize a modified HOGEN H Series industrial electrolyzer. The tritium amount transferred to hydrogen gas, the water enrichment factor, and the number of hours necessary to attain a steady-state regime were parameters of primary interest in the experiments. To minimize the necessary time for a steady-state regime, the holdup of the water electrolyzer was chosen as the minimum value allowed for safe and constant parameter operation in all experiments. The stationary regime was attained after 120 h, with an enrichment factor near 5, and an amount of 18% to 19% of tritium transferred from tritium-enriched water to hydrogen gas. These parameters were obtained in all three experiments, and the modeling software of isotope separation by electrolysis confirmed the results. [ABSTRACT FROM AUTHOR]

A current concern of researchers from the Experimental Pilot Plant for Tritium and Deuterium Separation (PESTD) within the National R&D Institute for Cryogenics and Isotopic Technologies in Rm. Valcea is the solution of a combined electrolysis catalytic exchange (CECE) isotopic separation process that aims to be part of a new liquid waste decontamination technology. The experimental installation, defined as module M1100, has interfaces with the PESTD process and auxiliary systems and is placed within the PESTD area. The installation has its own automation and control system that allows for safe operation. Two operating modes are presented. The first mode is in "open-circuit" mode to evaluate the individual separation performances of the two technological processes, water electrolysis and water-hydrogen catalytic isotopic exchange, respectively. The second mode is in "closed loop," which corresponds to the CECE isotopic separation process where the tritium/deuterium are concentrated in the water within the electrolyzer. The preliminary experimental investigations were performed with low-concentrated tritiated water (HTO; ~100 Bq/l] in order to have a reduced degree of contamination as the concentration of the processed water was increased (~1000 Bq/l). The evaluation of the separation performances was made by comparing correlations from direct measurements with the calculated ones provided by the software developed for the CECE isotopic separation process in the open-circuit operating mode. For the closed-loop operation mode, the data provided by the calculation program for the representation of the nonstationary CECE isotopic separation regime were compared with the measured data. The preliminary results show a good correlation between the measured and the calculated data considering these experiments were carried out mainly in order to improve the operating performance. [ABSTRACT FROM AUTHOR]

This study presents the theoretical and practical aspects of the new technique, namely Mat Glass - Thin Layer Chromatography (MG-TLC) and application of invasion model. Our research is focused on the development and clarification of the phenomena that occur in thin layer separation technique: process flow, spreading on mat glass surface, impregnation of porous layers and the improvement of the quality of thin layer chromatographic separations by overlapping some mat glass plates, over the chromatographic plates. The experiments have confirmed the possibility that the movement of the invasive type displacement, which occurs on rough surface will influence favorably the chromatographic separation processes. Good results have been obtained in separation of the lipophilic dyes and the hydrophilic dyes by small adjustments, e.g., height of the free zone of porous layer h, or the roughness of glass plates. The results obtained demonstrate that this method can be successfully used in thin layer chromatography technique being easy to apply and inexpensive compared with other methods derived from chromatography. [ABSTRACT FROM AUTHOR]