Design and Optimization of Pullulan-Isononanoate Films with Bioactive-Loaded Liposomes for Potential Biomedical Use

This study reports the synthesis and detailed characterization of pullulan-isononanoate (Pull-Iso), as well as the preparation and characterization of Pull-Iso films incorporating liposomes loaded with silibinin (SB) and smoke tree (Cotinus coggygria) extract (STExt), to explore the physicochemical and functional properties of pullulan-based biomaterials for potential biomedical applications. Pullulan was successfully esterified with isononanoic acid chloride, as confirmed by 1H and 13C NMR (Nuclear Magnetic Resonance) and Fourier Transform Infrared (FTIR) spectroscopy. Modification significantly reduced the glass transition temperature (Tg), indicating enhanced chain mobility due to the introduction of bulky side chains. Prepared liposomes, embedding SB and extracted smoke tree compounds, exhibited particle sizes ~2000 nm with moderate polydispersity (~0.340) and zeta potential values around –20 mV, demonstrating lower colloidal stability over 60 days, thereby justifying their encapsulation within films. Optical microscopy revealed uniform liposome dispersion in Pull-Iso film with 0.5 g of liposomes, while higher liposome loading (0.75 g of liposomes) induced aggregation and microstructural irregularities. Mechanical analysis showed a reduction in tensile strength and strain at higher liposome content. The incorporation of liposomes encapsulating STExt and SB significantly enhanced the antioxidant activity of Pull-Iso-based films in a concentration-dependent manner, as demonstrated by DPPH and ABTS radical scavenging assays. These preliminary findings suggest that pullulan esterification and controlled liposome incorporation may enable the development of flexible, bioactive-loaded films, which could represent a promising platform for advanced wound dressing applications, warranting further investigation

Hydrodynamics of a draft-tube spout–fluid bed with a hydraulic barrier: Minimum spouting velocity, flow regimes, and solids circulation

The Draft Tube Spout-Fluid Bed (DTSFB) with a hydraulic barrier represents an advanced modification designed to minimize gas bypass and prevent mixing of spouting and aeration gas streams. Experimental tests on flow regime, minimum spouting velocity (U ms ), and particle mass flow rate (G p ) were conducted in a cylindrical column with a diameter of 115 mm, using glass particles and air as the spouting and aeration fluids. Four flow regimes were visually identified at different spouting and aeration fluid flow rates: draft tube clogging, intermittent spouting, stable spouting with aeration, and bubble formation in the annulus. The effects of operating conditions and geometric parameters on the flow regimes, minimum spouting velocity, and particle mass flow rate were analyzed. The results showed that, due to the hydraulic barrier, the aeration fluid flow rate had a limited effect on U ms over a wide range of operating conditions, with a noticeable decrease only at high aeration fluid flow rates. A new correlation for calculating U ms is proposed, yielding an average relative deviation of 4.18%. In addition, a modified correlation for the dimensionless particle–wall friction factor is proposed, enabling reliable prediction of the particle mass flow rate

Poster: The thermomechanical and structural properties of PMMA/SiC films

Silicon carbide (SiC) microfibers were added as reinforcement in this study to improve thethermomechanical properties of poly(methyl methacrylate) polymer, PMMA, since this kind ofcomposite has not been fully investigated yet. The PMMA/SiC composite materials can betailored for possible use as buildable or protective films in flexible electronics. By casting, thinPMMA composite films containing 0.5 and 1.0 weight percent (wt.%) SiC microfibers were created. The addition of SiC microfibers allowed the PMMA/SiC composites to achieve higher thermal stability than the pure PMMA, according to the Differential Scanning Calorimetry (DSC)research. Compared to the pure PMMA film, the glass transition temperatures of PMMA/0.5wt.% SiC and PMMA/1.0 wt.% SiC films were approximately 2.4◦C and 3.5◦C higher, respectively. The findings also demonstrated that, in comparison with the neat PMMA film, thePMMA films with 0.5 wt.% and 1.0 wt.% SiC reinforcement had microhardness improvementsof 17.9% and 55.6%, correspondingly. The PMMA composite films were also characterized usingAtomic Force Microscopy (AFM). The PMMA/SiC films were rougher as a result of the additionof SiC microfibers to the PMMA polymer matrix. In comparison with the pure PMMA film,the average roughness values of the PMMA/SiC films were about 3.9 (with 0.5 wt.% SiC) and13.7 (with 1.0 wt.% SiC) times higher. The existence of a pile-up phenomenon following theindentation of PMMA films was confirmed by both optical and atomic force microscopy[ https://mecanano2026.sciencesconf.org/data/pages/book_mecanano2026_en_1.pdf]MecaNano General Meeting 2026, 27-29 Apr 2026, Rome, ItalyObradović V, Mladenović I, Vuksanović M, Radovanović Ž, Jovanov V. The thermomechanical and structural properties of PMMA/SiC films. in Book of Abstracts / MecaNano General Meeting 2026, 27-29 Apr 2026, Rome, Italy. 2026;:82-82..Abstract: [https://cer.ihtm.bg.ac.rs/handle/123456789/9259

The thermomechanical and structural properties of PMMA/SiC films

Silicon carbide (SiC) microfibers were added as reinforcement in this study to improve the thermomechanical properties of poly(methyl methacrylate) polymer, PMMA, since this kind of composite has not been fully investigated yet. The PMMA/SiC composite materials can be tailored for possible use as buildable or protective films in flexible electronics. By casting, thin PMMA composite films containing 0.5 and 1.0 weight percent (wt.%) SiC microfibers were created. The addition of SiC microfibers allowed the PMMA/SiC composites to achieve higher thermal stability than the pure PMMA, according to the Differential Scanning Calorimetry (DSC) research. Compared to the pure PMMA film, the glass transition temperatures of PMMA/0.5 wt.% SiC and PMMA/1.0 wt.% SiC films were approximately 2.4◦C and 3.5◦C higher, respectively. The findings also demonstrated that, in comparison with the neat PMMA film, the PMMA films with 0.5 wt.% and 1.0 wt.% SiC reinforcement had microhardness improvements of 17.9% and 55.6%, correspondingly. The PMMA composite films were also characterized using Atomic Force Microscopy (AFM). The PMMA/SiC films were rougher as a result of the addition of SiC microfibers to the PMMA polymer matrix. In comparison with the pure PMMA film, the average roughness values of the PMMA/SiC films were about 3.9 (with 0.5 wt.% SiC) and 13.7 (with 1.0 wt.% SiC) times higher. The existence of a pile-up phenomenon following the indentation of PMMA films was confirmed by both optical and atomic force microscopy[ https://mecanano2026.sciencesconf.org/data/pages/book_mecanano2026_en_1.pdf]Poster: [https://cer.ihtm.bg.ac.rs/handle/123456789/9260

Benefiti HORIZON EUROPE projekata

Prezentacija prikazuje osnivanje, razvoj i aktivnosti Kancelarije za projekte i međunarodnu saradnju (ICPO) na IHTM-u, formirane radi jačanja institucionalnih kapaciteta za učešće u međunarodnim programima finansiranja istraživanja. Predstavljene su razlike između nacionalnih projekata i programa Horizon Europe, uključujući administrativne zahteve, budžetske okvire i značaj međunarodne saradnje. Poseban akcenat stavljen je na ulogu ICPO u motivisanju istraživača, pružanju podrške pri pripremi i sprovođenju projekata, organizovanju obuka, info‑dana i aktivnosti izgradnje kapaciteta. Prikazani su ostvareni rezultati, poput povećanog učešća u Horizon Europe i COST akcijama, unapređenja istraživačke administracije i jačanja vidljivosti i kompetencija IHTM-a na međunarodnom nivou.The presentation provides an overview of the establishment, development, and activities of the International Cooperation and Project Office (ICPO) at ICTM, created to strengthen institutional capacity for participation in international research funding programmes. It outlines key differences between national and Horizon Europe projects, emphasizing administrative requirements, budgetary frameworks, and the strategic importance of international collaboration. The presentation highlights ICPO’s role in motivating researchers, supporting proposal preparation and project implementation, organizing training events and info days, and building both technical and transferable skills among research staff. Documented outcomes include increased participation in Horizon Europe and COST Actions, enhanced institutional visibility, and measurable improvements in research support services and project management capacities.Prezentacija u okviru radne posete Tehničkom fakultetu u Boru / Presentation given as part of a working visit to the Technical Faculty in Bo

Improving electrochemical aptasensor sensitivity for Bacillus cereus spore detection in food safety applications

Rapid detection of Bacillus cereus spores is essential for preventing food contamination and spoilage. Many existing methods detect B. cereus vegetative cells rather than spores and cannot be applied directly to foods. Here, we present a combination of aptamers targeting different moieties on the surface of B. cereus spores with rapid electrochemical detection. When DNA aptamers, previously selected for B. cereus spores, were immobilized on screen-printed gold electrodes, they exhibited higher binding capacity than individual aptamers, suggesting a synergistic effect. Additionally, the mixture of rhodamine-labelled aptamers enabled spatial fluorescent visualization of the B. cereus endospore structure, confirming the increased binding efficiency. The electrochemical aptasensor based on three aptamers exhibited a wide dynamic range (102–107 CFU/mL) and low limit of detection (∼1 CFU/mL) using just 15 μL of sample. Validation in spiked salad, using direct spore sensing in rinse water and comparison with the culturing method, confirmed its sensitivity and specificity. These combined aptamer approaches, achieving rapid (15 min) and single-step detection may also be suitable for detecting other foodborne pathogens.Supporting information: [https://cer.ihtm.bg.ac.rs/handle/123456789/9025

Industrialising novel technologies

Prezentacija koleginice iz dijaspore dr Ksenije Milicevic Neumann, suosnivača startup kompanije (tozero comany, Munich, Germany) i člana tima projekta REMEDIS. Predavanje je održala u okviru diseminacije projekta REMEDIS koji je finansiran od strane Fonda za nauku Republike Srbije. Za sva dodatna pitanja se možete obratiti rukovodiocu projekta dr Nataši Petrović ([email protected]

Long-term bioelectricity generation in microbial fuel cell exposed to perfluorooctanoic acid

The long-term performance of microbial fuel cells (MFCs) depends on microbial communities whose composition strongly influences electron transfer and substrate utilization. The presence of environmental pollutants can cause changes in microbial abundance and biodiversity and have an effect on the MFC efficacy; however, their long-term operational stability under environmental stress remains insufficiently explored. This study assessed the long-term performance of MFCs using river sediment organic matter as the energy, electron, and carbon source during exposure to perfluorooctanoic acid (PFOA). The MFC-PFOA (MFC with PFOA) system operated effectively for 10 months, achieving a maximum voltage of 461.9 mV and a peak current density of 14.5 mA/m2, significantly outperforming the control cell. Liquid chromatography–tandem mass spectrometry (LC-MS/MS) analysis confirmed a 94.9 % reduction in PFOA concentration and detected perfluoroheptanoic acid (PFHpA) and perfluorohexanoic acid (PFHxA), indicating possible partial transformation and/or redistribution processes within the bioelectrochemical system. Additionally, bacterial community analysis revealed a shift in microbial composition, with Firmicutes and Desulfobacterota becoming dominant, suggesting their roles in current gen- eration and biotransformation of PFOA. Overall, this work demonstrates long-term bioelectricity generation in the presence of per- and polyfluoroalkyl substances (PFAS) pollutants, while indicating partial attenuation and compositional changes of PFOA under bioelectrochemical conditions, thus providing valuable insights into the robustness of bioelectrochemical systems for energy recovery in contaminated environments

Influence of inevitable hydrogen evolution reaction on morphology of electrodeposited zinc

Influence of parallel hydrogen evolution reaction (HER) on morphology of zinc electrodeposits has been investigated. Zn was electrodeposited potentiostatically from the alkaline electrolyte at overpotentials both inside and outside the plateau of the limiting diffusion current density, and scanning electron microscopy (SEM) was used to characterize the resulting deposits. Holes originating from detached hydrogen bubbles were formed among the branchy, fern-like dendrites at overpotentials outside the plateau of the limiting diffusion current density, while HER was not detected at the overpotential inside the plateau. The overpotential of electrodeposition had no significant effect on the amount of hydrogen produced (the HER current efficiency was in the 17.7-19.1 % range), but it did affect the hole size. Depending on the overpotential of the electrodeposition, the size of holes was from several to about 100 m, including those obtained by a coalescence of neighbouring hydrogen bubbles, and decreased with the increasing overpotential. The absence of inhibition of dendritic growth in spite of a high value of evolved hydrogen was attributed to Zn, which belongs to the group of normal metals characterized by high values of both the exchange current density and the overpotential for hydrogen evolution

Novel N-doped carbon/Co/Co3O4 ternary composites derived by direct carbonization of ZIF-67: Efficient electrocatalysts for oxygen reduction reaction

Cobalt-containing zeolitic imidazole framework ZIF-67 was synthesized in high yield, and directly carbonized by different heating routes at 800 and 900 °C. The products of carbonization, C(ZIF-67)s, were comprehensively characterized in terms of elemental composition (FAAS, EDX, XPS), crystalline (XRD) and molecular structure (FTIR and Raman spectroscopies), morphology (SEM), electrical conductivity, textural (N2 physisorption), and electrochemical properties. It was found that C(ZIF-67)s represent novel meso/microporous ternary composites of the type N-doped carbon/Co/Co3O4, containing metallic Co nanoparticles (NPs) with cubic body-centred crystalline structure, and predominately amorphous Co3O4. They exhibited high electrical conductivity (up to 4.2 S cm−1), notable BET specific surface area (197–265 cm2 g−1), and almost doubled mesopore volume compared to the parent ZIF-67. The effects of carbonization conditions on the structure, physico-chemical properties, and performance of C(ZIF-67)s as electrode materials in electrocatalysis of oxygen reduction reaction (ORR) and charge storage were studied. All C(ZIF-67) composites showed excellent ORR electrocatalytic activity in 0.1 M KOH, with four-electron reduction pathway. The highest ORR activity (the onset potential of −0.13 V vs. SCE) showed the composite produced by gradual heating up to 800 °C followed by holding at that temperature for 3 h. This is attributed to its highest mesopore volume, appropriate meso/micropore structure, high surface content of heteroatom-containing active sites (C–O–C, Co–N, Co–O), high surface Co2+/Co3+ ratio and the presence of Co NPs. The applied direct carbonization of ZIF-67, without additives and post-synthetic modifications, was shown as a simple way to produce meso/microporous electroconducting composites with high potential in energy related applications