Faculty of Technology and Metallurgy
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Item type:Publication, TOWARDS SUSTAINABLE EXTRACTION OF OIL FROM APRICOT KERNELS(2026-02-12); Deep eutectic solvents (DES) are gaining attention as green alternatives to conventional volatile organic solvents for the extraction of natural products. Their ease of preparation from inexpensive, biodegradable components, along with low toxicity and tunable physicochemical properties, makes them promising candidates for designing eco-efficient extraction processes. In this work, four DES systems based on choline chloride (ChCl) as hydrogen bond acceptor and different hydrogen bond donors glycerol, lactic acid, acetic acid, and glucose were synthesized and evaluated as co-solvents with n-hexane for the ultrasonic-assisted extraction of oil from apricot kernels. The DESs were characterized in terms of pH, density (δ), viscosity (μ), and electrical conductivity (σ) to better understand how their physical properties influence extraction performance. Oil extraction experiments demonstrated that the DES composition and its physical properties have a marked impact on extraction efficiency. Under optimized ultrasonic conditions, the use of ChCl:AA (1:2) as a co-solvent with n-hexane yielded the highest oil recovery of 26.62%, surpassing pure n-hexane, which afforded only 24.10% under the same conditions. In contrast, ChCl:GLY (1:2), ChCl:LA (1:2), and ChCl:GLU (2:1) resulted in lower oil yields of 18.95%, 22.23%, and 13.26%, respectively. The superior performance of ChCl:AA is attributed to its combination of relatively low viscosity, and high conductivity, which collectively promote enhanced mass transfer, more efficient cell disruption, and improved solubilization of lipophilic components when assisted by ultrasonic cavitation. Overall, this study highlights the importance of tailoring the physicochemical properties of DES to maximize performance and demonstrates the potential of DES n-hexane systems as green, efficient, and scalable alternatives to conventional solvent based processes for the valorization of apricot kernel oil and other plant derived lipids. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Optimization of Oil Extraction Process from White Mustard Seeds Using Response Surface Methodology(National and University Library of the Republic of Srpska, 2024-02-21); ; In this study, response surface methodology (RSM) was used for the determination of the effect of two process parameters (extraction temperature and extraction time) and their interaction on the yield of the total extract from white mustard seeds (Sinapis alba l.), as well as the creation of a mathematical model, 3D response surface, and the establishment of an optimal extraction region. Ethanol 96% as a green solvent was employed to separate biological compounds from white mustard (Sinapis alba l.) seeds by applying ultrasound-assisted extraction (UAE). UAE was performed at the temperature of 25, 30, and 35℃ for a duration of 30, 60, and 90 min. UAE as a modern extraction technique showed great performance, while the ethanol solvent provided a high yield of compounds. The utilized RSM design adequately fit the experimental data with a high coefficient of determination (R2= 0.9365) and low mean absolute error (MAE= 1.12242). Estimated effects for the yield of the total extract showed that the extraction time, the temperature, and the interaction between time and temperature influenced positively, while the time-squared and the temperature-squared influenced negativity on the yield of the total extract. Analysis of variance showed that 2 effects have P-values less than 0.05. The optimal yield of the total extracted oil was 15.19% at the temperature of 35℃ for a duration of 70.3 min. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Preformulation Characterization of Hydroxypropyl Cellulose Microparticles for Drug Delivery Applications:A Basis for Rational Design and Process Optimization(HDKI, 2025) - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Recent Advances in Textile Functionalization Using Essential Oil-Based-Microcapsules with Antimicrobial Properties(University of Ljubljana, 2025); ; Editor-in-Chief Tatjana Rijavec; Assistant Editor Tatjana Kreže; Associate Editors Matejka Bizjak, Katja Burger Kovič, Andrej Demšar, Mateja Kos Koklič, Alenka Pavko Čuden, Andreja Rudolf, Barbara Simončič, Dunja Šajn Gorjanc, Sonja Šterman, Brigita Tomšič;Executive Editor for Databases Irena Sajovic; International Editorial Board Matej Bračič, Maribor, SI Snježana Brnada, Zagreb, HR Andrea Ehrmann, Bielefeld, DE Petra Forte Tavčer, Ljubljana, SI Jelka Geršak, Maribor, SI Marija Gorjanc, Ljubljana, SI Lubos Hes, Moka, MU Aleš Hladnik, Ljubljana, SI Svjetlana Janjić, Banja Luka, BA Mateja Kert, Ljubljana, SI Dragana Kopitar, Zagreb, HR Yordan Kostadinov Kyoshev, Dresden, DE Petra Komarkova, Liberec, CZ Mateja Kos Koklič, Ljubljana, SI Mirjana Kostić, Beograd, RS Manja Kurečič, Maribor, SI Boris Mahltig, Niederrhein, DE Subhankar Maity, Kanpur, IN Małgorzata Matusiak, Łódź , PL Ida Nuramdhani, Bandung, ID Alenka Ojstršek, Maribor, SI Roshan Paul, Aachen, DE Tanja Pušić, Zagreb, HR Ivana Salopek Čubrić, Zagreb, HR Snežana Stanković, Beograd, RS Jovan Stepanović, Leskovac, RS Dunja Šajn Gorjanc, Ljubljana, SI Mohammad Tajul Islam, Dhaka, BD Antoneta Tomljenović, Zagreb, HRAntimicrobial textiles are functionalized textiles designed to inhibit or terminate the growth of microorganisms. In light of the increasing emphasis on eco-friendly processes, the application of essential oils presents a viable alternative to synthetic drugs (antibiotics). The aim of this study was to evaluate recent advances in microencapsulation methods of essential oils with antimicrobial activity that can be applied on medical textile for dermal use by employing the PRISMA methodology. Essential oils have been microencapsulated using various methods: coacervation, spray-drying, emulsion method and in situ polymerization. Among these, coacervation is still extensively utilized, though associated scale-up challenges persist. Many essential oils have demonstrated antibacterial properties against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) bacteria, as well as antifungal activity (Candida albicans). The growth inhibition of these microorganisms was assessed in the presence of the following essential oils and their active substances with the highest biological-antimicrobial activity: cinnamon (transcinnamaldehyde), lime (α-terpineol, terpineol, and limonene), tea tree (terpinen-4-ol), rosemary (1,8-cineole and α-pinene), peppermint (l-menthol, menthone, methyl acetate and limonene), lavender (linalool and linalyl acetate), thyme (carvacrol) and clove (eugenol). The findings indicate that functionalized textile with microcapsules exhibits enhanced antibacterial activity against Gram-positive bacteria compared to Gram-negative bacteria (Escherichia coli), which could be attributed to the bacteria’s thick wall. However, there is a notable lack of data regarding cytotoxicity and the sensory evaluation of functionalized textile. The potential utilization of essential oils was explored in the development of eco-friendlier functionalized textile with antimicrobial properties. However, additional research is required to maximize the antimicrobial activity of microcapsules to overcome challenges in the scale-up to pilot process, and to improve the immobilization in textiles. Keywords: antimicrobial properties, sustainability, essential oils, microcapsules, textile functionalization - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Electrochemical sensors based on polymer-modified screen-printed graphene electrodes for the detection of pharmaceuticals in aquatic environments(SAGE Publications, 2025-10-06); - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Smartphone-Based Digital Image Processing for Fabric Drape Assessment, Textiles, 2025, 5(4), 63; https://doi.org/10.3390/textiles5040063(MDPI, 2025)Emilija Toshikj, Nina MladenovikjFabric drape characterization is vital for textile performance and aesthetics, but the conventional Cusick method is labor-intensive and incompatible with digital workflows. This study assesses a smartphone-enabled digital image processing (DIP) method for fabric drape coefficient (DC) measurement, providing an accessible, low-cost alternative to the Cusick method. Draped specimens of light, medium, and heavy fabrics were imaged at three diameters (24, 30, and 36 cm) using a smartphone positioned at three vertical distances (22, 32, and 42 cm). DCs were determined through pixel-based analysis in Adobe Photoshop®, ImageJ®, and MATLAB®. Statistical comparison against the Cusick method employed F-tests for variance, two-sample t-tests for mean differences, and skewness analysis. No statistically significant differences were found between smartphone DIP (with either the iPhone or Samsung device) and Cusick measurements (p > 0.05). Neither imaging height nor software platform significantly influenced outcomes, though a 22 cm height consistently provided the most stable conditions. ImageJ® was identified as an effective open-source option for reliable analysis. The findings establish a reliable, cost-effective, and portable method for drape evaluation, reducing technical and economic barriers while aligning with Industry 4.0 digitalization. This approach enables broader adoption of reliable textile characterization across research, industry, and domains. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Smartphone-Based Digital Image Processing for Fabric Drape Assessment, Textiles, 2025, 5(4), 63; https://doi.org/10.3390/textiles5040063(Textiles, 2025)Emilija Toshikj, Nina MladenovikjFabric drape characterization is vital for textile performance and aesthetics, but the conventional Cusick method is labor-intensive and incompatible with digital workflows. This study assesses a smartphone-enabled digital image processing (DIP) method for fabric drape coefficient (DC) measurement, providing an accessible, low-cost alternative to the Cusick method. Draped specimens of light, medium, and heavy fabrics were imaged at three diameters (24, 30, and 36 cm) using a smartphone positioned at three vertical distances (22, 32, and 42 cm). DCs were determined through pixel-based analysis in Adobe Photoshop®, ImageJ®, and MATLAB®. Statistical comparison against the Cusick method employed F-tests for variance, two-sample t-tests for mean differences, and skewness analysis. No statistically significant differences were found between smartphone DIP (with either the iPhone or Samsung device) and Cusick measurements (p > 0.05). Neither imaging height nor software platform significantly influenced outcomes, though a 22 cm height consistently provided the most stable conditions. ImageJ® was identified as an effective open-source option for reliable analysis. The findings establish a reliable, cost-effective, and portable method for drape evaluation, reducing technical and economic barriers while aligning with Industry 4.0 digitalization. This approach enables broader adoption of reliable textile characterization across research, industry, and domains. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, REDUCING THE BAND-GAP ENERGY OF TiO2 AS A CRUCIAL OBJECTIVE IN GREEN PHOTOCATALYSIS(Ss Cyril and Methodius University in Skopje, Faculty of Technology and Metallurgy, 2025-06-12)Perica Paunović, Anita Grozdanov, Petre Makreski, Martin Stojčevski, Kiril Stoimčev, Gorazd ČepiševskiGreen photocatalysis focuses on developing processes to address various environmental challenges, such as the treatment of contaminated water and air, the generation of renewable energy, biomass management, carbon monoxide oxidation, and organic synthesis. TiO2 nanoparticles are relatively inexpensive, non-toxic, and chemically stable. They are available in diverse structural forms and exhibit unique semiconductive properties, making them the most widely utilized photocatalysts in this domain. TiO2 has a wide array of applications in green photocatalysis, including i) photocatalytic remediation and ii) the development of alternative, sustainable energy sources. A significant challenge in modern green photocatalysis is the reduction of the band gap energy (Eg), which is essential for determining the suitability of materials for photocatalytic activity. Decreasing Eg enables TiO2 to effectively harness visible light rather than being limited to ultraviolet light. This study investigates the structural changes and subsequent reduction in Eg resulting from two types of TiO2 modification: i) ionizing irradiation and ii) the incorporation of carbon nanotubes. We synthesized TiO2 nanoparticles using our proprietary sol-gel method, followed by thermal treatment at 400 °C. Structural changes were analyzed using X-ray powder diffraction (XRPD) and Raman spectroscopy, while the band gap energy of the samples was assessed through UV-Vis spectroscopy. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Polymer-modified screen-printed electrode-based electrochemical sensors for doxorubicin detection(The Association of South-East European Electrochemists (ASEEE), 2025-02-27)Iva Dimitrievska, Perica Paunovikj, Anita GrozdanovIn the last decade, intensive research has been performed in the field of analytical electrochemistry, seeking designs of electrochemical sensors capable of providing better analytical characteristics in terms of sensitivity, selectivity, reliability, ease of fabrication and use, and low cost, especially for pharmaceutical drug monitoring. Our research has primarily focused on developing screen-printed electrode-based sensors and their application as electrochemical platforms for drug determination and monitoring, specifically emphasizing their suitability for surface modification. A commercial screen-printed graphene electrode was used as the electrochemical sensing component, which was subsequently modified with polymers, such as polyvinylidene fluoride and chitosan. All studied electrodes were tested using a doxorubicin hydrochloride (DOX) solution with a concentration of 0.002 mol L-1 dissolved in 0.1 mol L-1 phosphate-buffered saline at pH 6.7. Cyclic voltammetry was used as an electrochemical characterization technique to gather data on all tested electrodes' electrochemical activity. The morphological characterization of the electrodes was done using scanning electron microscopy. The changes in the electrolyte during the electrochemical measurements were followed through ultraviolet-visible spectroscopy. The modified electrodes demonstrated a favorable electrochemical response to DOX and exhibited higher electrical conductivity than the commercial one. The characterization results indicated that the Ch-modified electrode exhibited excellent electrochemical conductivity and demonstrated strong electrochemical performance. The evaluations of this electrode comprised the definition of the lowest limit of detection and limit of quantification among the tested electrodes, with values of 9.822 and 32.741 µmol L-1, respectively, within a linear concentration range from 1.5 to 7.4 µmol L-1. Additionally, the electrodes showed excellent repeatability, stability, and reproducibility, confirming their suitability for sensitive DOX detection. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Influence of irradiation treatment on sensing performances of screen-printed electrodes aimed for doxorubicin monitoring(Association of South-East European Electrochemists (ASEEE), 2025-05-05)Perica Paunovikj, Iva Dimitrievska, Marija Katerina Paunovikj, Marija Mitevska, Anita GrozdanovThe subject of study is the development of nanosensors based on carbon nanotubes (CNTs) and polyaniline (PANI) aimed at effective detection and monitoring of doxorubicin - a chemotherapy drug used in the treatment of different types of cancer. The main goal is the design of nanosensors that provide precise and reliable detection and monitoring of doxorubicin, providing an effective approach to monitor drug levels during treatment. The research was carried out on the screen-printed electrodes (SPE) with a working electrode of commercial CNTs and PANI and their modification by irradiation with electron irradiation (50 kGy). The structural changes resulting from the e-beam irradiation were observed by scanning electron microscopy, Raman and FTIR spectroscopy, and thermogravimetric analysis. An electrochemical study employing cyclic voltammetry was done to characterize and test the performance of the nanosensors. Modification with electron irradiation was shown as an effective approach to improve the sensing characteristics of the studied SPE, resulting in a lower limit of detection for the modification. The irradiated SPEs exhibit a limit of detection of 12.674 µmol L⁻¹ for the modified multi-walled CNT (MWCNT) electrode and 12.712 µmol L⁻¹ for the modified PANI electrode, compared to 12.773 µmol L⁻¹ for the MWCNT and 12.712 µmol L⁻¹ for the PANI commercial electrodes.
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