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Electrochemical investigation of Rh(III) Schiff base complex and its interaction with human serum albumin
No full textThe electrochemical properties of a Schiff base ligand and its rhodium(III) complex were
investigated in aqueous (PBS, pH 7.4) and non-aqueous solvents (acetonitrile,
dimethylformamide). Distinct differences in electrochemical behavior were observed
depending on the solvent, with aprotic media providing more defined and stable signals.
For the study of protein binding, phosphate buffer saline with 10 mM NaCl was selected
as the medium to examine the interaction of the Rh(III) complex with human serum
albumin (HSA). Cyclic voltammetry was employed to monitor these interactions, and
the obtained binding constants (10⁴–10⁵ M⁻¹) indicated an optimal binding affinity.[1]
These findings suggest favorable pharmacokinetic properties of the Rh(III) complex,
highlighting its potential as a novel therapeutic agent or drug carrier
Sawdust-templated lace-like DyBO3 microstructure for instant hydroquinone sensing
No full textHydroquinone (HQ) contamination of water became a serious problem as this chemical consumption shows constant growth with application as a preserving component in a huge number of products for domestic and industrial use. Little control of its release from various wastes could pose a long-term hazard to public health. To avoid it, quick and reliable methods are required to provide necessary information about levels and dynamics of HQ contamination in water, food and products of domestic consumption. Electrochemical methods are a simple and affordable means of analytical detection of various chemicals, with selectivity and sensitivity often comparable with chromatographic and spectrometric assays. Screen-printed electrodes (SPE) as a plane version of the three-electrode cell significantly simplified application of the EC-methods, although compromised their stability and sensitivity. Major efforts are concentrated on improving these SPE characteristics. Here, we approach the development of a reliable SPE-based assay for hydroquinone analysis with a hierarchically structured rare-earth borate as a perspective electroactive binary oxide. Template synthesis of crystalline dysprosium borate using a pine sawdust provided structures exhibiting a multi-level structural hierarchy. The obtained borate with sophisticated morphology showed excellent electrochemical properties, which were used in the development of a hydroquinone (HQ) sensor with an improved linearity range and a low detection limit. The repeatability and stability of the sensor were satisfactory for real-time measurements
Sustainable Poly (Methacrylic Acid)/Nanocellulose Hydrogel for Controlled Simultaneous Release of Active Substances for Skin Protection
No full textHydrogels based on poly (methacrylic acid), carboxymethyl cellulose, and nanocellulose
fibers were successfully synthesized, characterized, and tested as topical carriers for the controlled
release of hydrophobic resveratrol and hydrophilic acetyl glucosamine, active substances
used in skin protection. Carrier composition was confirmed by Fourier-transform
infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed the pore size
variations with alterations in the neutralization degree of methacrylic acid and changes
in the pore-wall roughness caused by different mass fractions of nanocellulose. The neutralization
degree of methacrylic acid had a substantial impact on the swelling behaviour,
while only a slight change in swelling was caused by various contents of nanocellulose
in hydrogels. Mechanical properties of the hydrogels accessed by compressive strength
measurement at various percentages of strain were improved by the addition of nanocellulose.
Hydrogels containing 0.5% nanocellulose achieved the highest compressive strength.
The neutralization of methacrylic acid reduced the mechanical properties. Hydrogels with
optimal properties showed outstanding potential in encapsulation, and controlled the
simultaneous release of resveratrol and N-acetyl glucosamine. The different nature of the
active compounds, however, affected the release kinetics and mechanism, as confirmed by
the Korsmeyer–Peppas model
Harmonizing Data for Dietary Microplastic Exposure: Insights into Seafood and Age Specific Risks
No full textOver recent decades, the rapid increase in plastic production has led to heightened concerns about the pervasive presence of microplastics (MPs) in the environment. Defined as particles smaller than 5 mm, MPs are increasingly detected in various food categories, raising questions about human exposure and associated health risks. This study aims to evaluate dietary exposure to MPs, with a specific focus on seafood, and to assess the contribution of various food grou ps to total MP exposure. To address this challenge, we reviewed existing data on MP occurrence in bivalves and crustacea and analyzed findings from a previous study involving 218 food items purchased from mainstream food retailers. We employed exposure assessment techniques to estimate daily MP intake across three age groups (children, adolescents and adults), considering realistic and worst-case scenarios. Special attention was given to aligning and comparing data from diverse sources using standardized methodologies. Our results indicate that adults have an average MP exposure of up to 0.37 MP per kilogram of body weight per day under realistic conditions. In contrast, children experience the highest exposure, reaching 4.19 MP per kilogram of body weight per day in worst-case scenarios. These findings highlight significant variability in exposure levels based on age and dietary habits. This study highlights the critical need for harmonized methodologies to synthesize data from diverse sources, particularly in evaluating seafood as a major contributor to dietary microplastic (MP) exposure. MPs in food may act as vectors, potentially transporting contaminants and allergens, making them more significant for secondary risks than nanoplastics (NPs), which are more concerning due to their distinct toxicological profiles. By improving our understanding of MP ingestion
through food, this research provides a foundation for future investigations into exposure sources,
associated health risks, and strategies for mitigation. The research that yielded MP occurrence results, was funded by the Belgian Federal Public Service Health, Food Chain Safety and Environment through the contract RT 18/05 Plastic_in_Food. The complementary study and the literature review was done in the scope of IMPTOX project which was funded by The EU s H2020 framework program for research and innovation, grant number 965173 entitled An innovative analytical platform to investigate the effect and toxicity of micro and nanoplastics (MNPs) combined with environmental contaminants on the risk of allergic disease in pre-clinical and clinical studies
Sadržaj mikroelemenata u uzorcima cervikalnog tkiva žena sa dijagnostikovanom cervikalnom intraepitelnom neoplazijom
No full textCilj ovog rada bio je da se ispita sadržaj esencijalnih i toksičnih mikroelemenata u uzorcima
tkiva cervikalne intraepitelne neoplazije i da se dobijeni rezultati uporede sa uzorcima zdravog
cervikalnog tkiva. Poređenjem ovih podataka nastoji se utvrditi da li postoje značajne razlike u
koncentracijama mikroelemenata između obolelog i zdravog tkiva.
Na taj način se može dobiti bolji uvid u ulogu mikroelemenata u nastanku i razvoju CIN-a, što može
doprineti boljem razumevanju oboljenja i preciznijoj proceni rizika od razvoja karcinoma grlića materice
Оrganic acids as promising authenticity markers of Robinia pseudoacacia honey
No full textIn recent years, the honey-producing sector has faced the increasing presence of adulterated honeys, implying great economic losses and questioning about product quality. This study aimed to develop and optimize an ion chromatographic method capable of accurately measuring individual organic acids concentrations in honey samples and differentiate authentic Robinia pseudoacacia honey from adulterated samples. Results revealed that citric, isocitric, succinic and glucuronic acids were dominant variables responsible in distinguishing authentic from adulterated commercial honey samples. The proposed method proved to be promising and reliable in verifying authenticity of acacia honey based on citric and isocitric acids content. This method offers advantages in cost, time consumption, efficiency, and environmental impact over other methods, eliminating the need for derivatization pretreatment and offering a straightforward "dilute and shoot" approach. Moreover, it could potentially compete with commonly used standard EA-IRMS method, avoiding time-consuming preprocessing and isotopic fractionation risks
Analytical performance and stability studies of CoAu/rGO-based electrochemical sensor for arsenic(III) detection in aqueous solutions
No full textCobalt-gold nanoparticles (CoAu) were grafted on reduced graphene oxide (rGO) using a simple and scalable procedure. As-prepared CoAu/rGO nanocomposites were employed as electrode materials to detect trace amounts of arsenic(III) ions (As3+) in aqueous solutions using anodic stripping voltammetry. CoAu/rGO was thoroughly tested in the presence of As3+ in a neutral medium (bicarbonate buffer, pH = 7), and the limit of detection was found to be as low as 1.51 ppb, significantly lower than the maximum permissible value set by the World Health Organization at 10 ppb. Its possible sensor application was confirmed by the preserved response to As3+ ions in samples simultaneously containing interferents such as Cu2+ ions. The real-life application of this material was validated by the determination of As3+ ions in real samples from the city water supply system (the city of Zrenjanin in Vojvodina) and rivers (the Begej River, the Drina River and the Danube River). Besides the high sensitivity of CoAu/rGO towards As3+ ions, its stability was also monitored over a certain time, demonstrating that it can be used with great precision in sensors for routine water analysis over extended periods. Overall, this study offers a green, highly stable, accurate and precise electrochemical platform for arsenic detection that requires reagent-free sample preparation
Multidisciplinary Bioanalytical Approach to Assess the Anti-Aging Properties of Flower Petals—A Promising Sustainable Cosmetic Ingredient
No full textThe increasing demand for natural, safe, and sustainable ingredients is driving innovation in cosmetic science. This study assessed the anti-aging potential of 17 petal extracts using a multidisciplinary bioanalytical approach. In vitro spectrophotometric assays evaluated anti-wrinkle (anti-elastase), anti-pigmentation (anti-tyrosinase), and antioxidant (DPPH, ABTS) activities, while cytotoxicity was tested on HaCaT keratinocytes. Chemical profiling using HPTLC and UHPLC–MS/MS identified 17 phenolic compounds. For the first time, petals from prairie rose (Rosa setigera Michx.), common peony (Paeonia officinalis L.), horse-chestnut cultivars (Aesculus hippocastanum L., Aesculus × carnea Zeyx.), lilac (Syringa vulgaris), mock-orange (Philadelphus pubescens Loisel), orange lily (Lilium bulbiferum L.), garden tulip (Tulipa gesneriana L.), ivy geranium (Pelargonium × peltatum (L.) L’Hér. ex Aiton), and wallflower (Erysimum × cheiri (L.) Crantz) were studied for their skin anti-aging properties. Prairie rose, peony, and ivy geranium extracts showed strong anti-elastase activity; rose and peony also demonstrated high antioxidant potential, while lilac exhibited significant anti-tyrosinase effects. Key phenolic constituents—caffeic acid, p-coumaric acid, and gallic acid—were further examined via molecular docking, which confirmed their inhibitory properties by revealing inhibition mechanisms. All extracts were confirmed to be non-toxic in zebrafish acute toxicity assays at relevant concentrations. This integrative strategy effectively links chemical composition with biological activity, offering valuable insight into the development of safe, plant-derived anti-aging agents for sustainable cosmetic applications
Implementation of a Novel Nanobody Panel for the Efficient Capture of Extracellular Vesicles from Human Plasma
No full textExtracellular vesicles (EVs) are nanoscale particles released by cells and are significant components in intercellular communication. Their ability to reflect the molecular state of parental cells and their presence in body fluids make them increasingly recognized as promising non-invasive biomarkers for different pathological conditions. However, the existence of different EV populations and frequent co-isolation of contaminants present challenges for EV purification and downstream analyses. In this study, we used three novel nanobodies (VHH) for selective isolation of EVs from human plasma. Nanobodies were obtained by direct panning on EVs. All examined nanobodies have excellent physicochemical properties resulting in excellent expression and solubility. The three nanobodies being studied—NA8, ND101, and ND102—share a conserved VHH scaffold but exhibit different loop architectures. The Biopython ProtParam module was used for calculation of VHH physicochemical properties, while sequence alignments for evaluation of variations were performed with the Biopython pairwise2 module. In addition, structural modeling of nanobodies with AlphaFold revealed notable differences in CDR3 conformations. VHH were produced in E. coli, and upon immobilization onto a solid carrier, they were used for immunoaffinity-based capture of EVs from human plasma. Combined characterization of isolated EVs supports efficient application of an immunoaffinity-based system based on such nanobodies for the isolation of EVs from human plasma to be used for downstream analyses
New Anti-HIV Agents Isolated From Two Euphorbia Species
No full textFour previously unreported tigliane diterpenes (1, 2, 4, and 6), along with two known tiglianes (3 and 5), were isolated from the latex of Euphorbia palustris and Euphorbia lucida. The structures of the isolated compounds were elucidated by spectroscopic techniques. Antiviral activity assays for compounds 1‒4 and 6 against HIV-1 and HIV-2 replication were performed on a CD4+ T cell line, MT-4 cells. The compounds were tested for their ability to inhibit infection by the HIV-1 strain NL4.3 and the HIV-2 strain ROD. Compound 6 showed no activity against either strain, while compound 4 was only slightly active against HIV-2 (EC50 = 12.778 µM). Compounds 1, 2, and 3 were able to inhibit both HIV-1 and HIV-2 infections. Among them, compound 2 was the most potent, with EC50 values of 0.069 µM for HIV-1 NL4.3 and 0.023 µM for HIV-2 ROD. The PBMC toxicity profile for compound 2 is also more favorable compared with MT-4 cells with CC50 = 50 μM