Astrid Ortner

In this study, a novel electroanalytical platform for the sensitive quantification of vanillin, an essential flavouring substance widely utilized in various industries, is presented. The design of the platform involves the modification of a glassy carbon paste electrode (GCPE) with copper nanoparticles decorated multi‐walled carbon nanotubes (MWCNTs). The developed copper nanoparticles_decMWCNTs/GCPE modified electrode exhibited a wide linear range (2.5–320 nM) with a detection limit of 0.7 nM. Interference tests confirmed the selectivity of the electrode in determining vanillin in complex matrices. The analysis of commercial samples of vanillin demonstrated its accuracy, yielding 92–103% recovery for vanillin content in commercial products. Furthermore, the electrode′s performance was validated through a comprehensive comparison of the electrochemical method with a well‐established high‐performance liquid chromatography (HPLC) method. The congruence between the electrochemical measurements and the HPLC data highlights its accuracy and shows its potential as a reliable alternative for vanillin quantification. The electrode′s exceptional sensitivity, selectivity, and accuracy position it as a valuable analytical method in various applications, including food quality assessment and other industries requiring rapid and precise analytical methods.

This study focused on creating a highly effective sensor for detecting and quantifying the nitrogen-organic pollutant metol (MTL). For this purpose, samarium molybdate (Sm2(MoO4)3) nanoparticles were synthesized using an eco-friendly, organic solvent-free and cost-effective hydrothermal method. These nanoparticles were used as a modifier of carbon paste electrodes (CPE), showing exceptional catalytic efficiency. Electrochemical measurements revealed that the developed electrode facilitates electron transfer processes and enhances the catalytic response. The resulting Sm2(MoO4)3/CPE sensor exhibited a broad linear range of 0.1?100 and 100?300 ?M of MTL, with low detection and quantification limits of 0.047 and 0.156 ?M, respectively, at pH 3 in a Britton?Robinson buffer solution (BRBS) as the supporting electrolyte. The findings from the analysis of real water samples from various sources using this sensor were encouraging, suggesting that this method could offer a cost- -effective, rapid and sensitive sensor for ambient MTL monitoring.

In this work, a novel electrochemical assay for characterizing both lipases and lipase inhibitors as well as for the determination of lipase activity is described. It is based on a carbon paste electrode, modified with cobalt(II)phthalocyanine, and multi-walled carbon nanotubes (MWCNTs). As reaction media, a sodium borate buffer was used (0.1 M, pH 9). The measurements were carried out in a batch system using differential pulse voltammetry (DPV) and 1,3-dilinolein as standard substrate. The activity assay showed a linearity for porcine pancreas lipase activity in a range between 20 and 300 U L⁻¹ (per min) with a limit of detection (LOD) of 7 U L⁻¹ and a limit of quantification (LOQ) of 20 U L⁻¹. The kinetic behavior of the lipase reaction was investigated, resulting in a K_M value of 0.29 mM. The applicability of the activity assay could be shown by investigating the activity of lipases from Aspergillus oryzae and Candida rugosa, and the results were confirmed by a reference method. The inhibitory effects were characterized with Orlistat. Graphical abstract

5-Hydroxymethylfurfural (5-HMF) is known to increase hemoglobin oxygen affinity (Hb–O₂ affinity) and to induce a left shift of the oxygen dissociation curve (ODC). It is under investigation as a therapeutic agent in sickle cell anemia and in conditions where pulmonary oxygen uptake is deteriorated or limited (e.g., various clinical conditions or altitude exposure). The combination of 5-HMF and α-ketoglutaric acid (αKG) is commercially available as a nutritional supplement. To further elucidate dose effects, ODCs were measured in vitro in venous whole blood samples of 20 healthy volunteers (10 female and 10 male) after the addition of three different doses of 5-HMF, αKG and the combination of both. Linear regression analysis revealed a strong dose-dependent increase in Hb–O₂ affinity for 5-HMF (R² = 0.887; p < 0.001) and the commercially available combination with αKG (R² = 0.882; p < 0.001). αKG alone increased Hb–O₂ affinity as well but to a lower extent. Both the combination (5-HMF + αKG) and 5-HMF alone exerted different P50 and Hill coefficient responses overall and between sexes, with more pronounced effects in females. With increasing Hb–O₂ affinity, the sigmoidal shape of the ODC was better preserved by the combination of 5-HMF and αKG than by 5-HMF alone. Concerning the therapeutic effects of 5-HMF, this study emphasizes the importance of adequate dosing in various physiological and clinical conditions, where a left-shifted ODC might be beneficial. By preserving the sigmoidal shape of the ODC, the combination of 5-HMF and αKG at low (both sexes) and medium (males only) doses might be able to better maintain efficient oxygen transport, particularly by mitigating potentially deteriorated oxygen unloading in the tissue. However, expanding knowledge on the interaction between 5-HMF and Hb–O₂ affinity in vitro necessitates further investigations in vivo to additionally assess pharmacokinetic mechanisms.

Background: Treating patients with inflammatory joint diseases (rheumatoid arthritis, psoriatic arthritis) according to established treatment algorithms often requires the simultaneous use of three or more medications to relieve symptoms and prevent long-term joint damage as well as disability. Objective: To assess and give an overview on drug-drug interactions in the pharmacotherapy of inflammatory joint diseases with regards to their clinical relevance. Methods: All possible drug combinations were evaluated using three commercially available drug interaction programs. In those cases where only limited/no data were found, a comprehensive hand search of Pubmed was carried out. Finally, the drug–drug interactions of all possible combinations were classified according to evidence-based medicine and a specifically generated relevance-based system. Results: All three interaction software programs showed consistent results. All detected interactions were combined in clearly structured tables. Conclusion: A concise overview on drug-drug interactions is given. Especially in more sophisticated cases extensive knowledge of drug interactions supports optimisation of therapy and results in improved patient safety.

A multi-component solution, containing α-ketoglutaric acid (α-KG), 5-hydroxymethylfurfural (5-HMF), N-acetyl-seleno-l-methionine (NASeLM), and N-acetyl-l-methionine (NALM) as active ingredients, has been tested considering its supposed antioxidative effect with respect to heart transplantations. Oxidative stress was induced on isolated rat hearts through occlusion of a coronary artery and in chicken heart tissue through hydrogen peroxide. Both heart types were analyzed and the oxidative stress markers malondialdehyde (MDA) and carbonyl proteins (CPs) were determined via HPLC/UV–Vis. In both approaches, it was found that treatment with the multi-component solution led to a lower amount of MDA and CPs compared to a negative control treated with Krebs–Ringer solution (KRS). Further investigation on chicken heart tissue identified α-KG as antioxidative component in these experiments. However, numerous factors like arrhythmia, vessel dilatation, and minimization of oxidative stress effects play an important role for successful transplantation. Therefore, the investigated multi-component solution might be a novel approach against oxidative stress situations, for example at ischemia reperfusion injury during heart transplantations.