1. Bacterial nanocellulose-based composite membranes for fuel cells applicationsSara Zdovc, Maša Hren, Selestina Gorgieva, 2026, pregledni znanstveni članek Opis: Bacterial nanocellulose (BnC) has shown potential as a suitable biopolymer for the development of sustainable ion exchange membranes (IEMs) for fuel cell (FC) applications. However, native BnC exhibits limited ionic conductivity due to its low charge density, requiring functional modifications to meet the performance demands of FC technologies. Although several reviews have addressed biopolymer-based membranes in general, BnC is typically only briefly mentioned and is often grouped within the broader group of nanocellulose, without a systematic focus on its role as an ion-conducting matrix. In response, this review provides a detailed and critical overview of recent advances in the development, modification, and application of BnC-based proton exchange membranes (PEMs) and anion exchange membranes (AEMs). The review highlights natural (e.g. lignin, fucoidan) and synthetic (e.g. Nafion®, PSSA, AMPS, PMACC, polymeric ionic liquids) additives used to enhance the ionic conductivity, selectivity, and durability of membranes. Key topics discussed include membrane structure, ion transport mechanisms, electrochemical performance in membrane electrode assemblies (MEA), and comparisons with commercial synthetic IEMs. This review examines the effect of BnC-based membrane composition on properties relevant to FC applications, while emphasising that BnC is an environmentally friendly and economically viable alternative to synthetic IEMs for next-generation FC systems.
Ključne besede: bacterial nanocellulose, ion exchange membrane, proton exchange membrane, anion exchange membrane, fuel cells
Objavljeno v DKUM: 19.12.2025; Ogledov: 0; Prenosov: 3
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2. Razvoj učnih pripomočkov in učil za poučevanje matematike : magistrsko deloJure Plejić, 2025, magistrsko delo Opis: Pri poučevanju geometrije se učenci pogosto srečujejo s težavami pri vizualizaciji teles ter z razvojem prostorskih predstav. Obstoječi učni pripomočki so največkrat ali preveč krhki in se hitro poškodujejo ali pa cenovno težko dostopni in zato redkeje uporabljeni. V raziskavi tega magistrskega dela je bil namen razviti prototip učnega kompleta učil, ki bi bil didaktično ustrezen, cenovno ugoden in dovolj trpežen za uporabo v osnovnošolskem okolju. V teoretičnem delu smo analizirali veljavni učni načrt za matematiko in pregledali obstoječa učila, pri čemer smo ocenili njihovo didaktično vrednost, enostavnost uporabe, cenovno dostopnost in trajnost. V praktičnem delu pa smo z uporabo CAD orodij, laserskega rezanja ter strojnega in ročnega obdelovanja razvili in izdelali prototipe geometrijskih teles z mrežami, ki jih je mogoče razpreti v vse izvedljive postavitve. Izdelani prototipi so se izkazali kot trpežni, cenovno dostopni in primerni za ponovljivo izdelavo tudi v osnovnošolskem okolju. Zato smo pripravili tehnično in tehnološko dokumentacijo, ki učiteljem omogoča samostojno izdelavo. Naši prototipi imajo potencial za vključevanje v pouk matematike, saj omogočajo bolj nazoren prikaz različnih postavitev mrež, pomagajo pri razvoju prostorskih predstav ter spodbujajo sodelovalno in raziskovalno učenje.
Ključne besede: učni pripomočki, učila, geometrijska telesa, matematika
Objavljeno v DKUM: 26.11.2025; Ogledov: 0; Prenosov: 13
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3. High oxygen barrier chitosan films neutralized by alkaline nanoparticlesUrška Jančič, Mojca Božič, Silvo Hribernik, Tamilselvan Mohan, Rupert Kargl, Karin Stana-Kleinschek, Selestina Gorgieva, 2021, izvirni znanstveni članek Opis: The most frequent neutralisation procedure, applied on chitosan (CS) films includes treatment with NaOH base. Such treatment endows CS films with stability in water, yet, same can significantly decrease the film performance. In the present paper, we investigate Mg(OH)2 nanoparticles as a neutralisation agent for CS solutions followed by casting into films. This is combined and compared with classical casting and film drying from nonneutralized solutions followed by NaOH treatment after film formation. The influence on the properties of resulting films is investigated in detail and large differences are found for structure and barrier properties. The stable, opaque-to-transparent CS films (depending on Mg(OH)2 content and post-treatment) were obtained by facile casting method of neat CS or CS–Mg(OH)2 dispersions, in the complete absence of cross-linkers and plasticizers. FTIR data demonstrate
the Mg(OH)2 and NaOH deprotonation effect, and strongly suggest intensive H-bonding interaction between CS and Mg(OH)2. X-ray photoelectron spectroscopy showed differences in the hydroxide content and protonation of CS nitrogen. The reduction of surface roughness and increase of homogeneity, the tensile strength and elongation, as well as thermal stability and excellent oxygen barrier properties were measured for CS enclosing the Mg(OH)2 nanoparticles. Further treatment with 1 M NaOH causes repacking of CS polymer chains, improving the crystallinity and water vapour barrier properties, degrading the mechanical properties by increasing the films brittleness and increasing the char formation due to reduced thermal stability.
Ključne besede: CS films, Mg(OH)2, neutralization, oxygen barrier properties
Objavljeno v DKUM: 14.10.2025; Ogledov: 0; Prenosov: 2
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4. Razvoj protimikrobnih lastnosti bakterijske nanoceluloze z uporabo bio-osnovanih komponent : magistrsko deloKatja Ravnjak, 2025, magistrsko delo Opis: Trajnostnost je trenutno eden izmed najpomembnejših konceptov, kamor sodi načelo zaščite pred izčrpavanjem naravnih virov ter koncept zelene kemije. Z željo po implementaciji le-tega se razvijajo nove tehnologije pridobivanja naravnih materialov, uporaba le-teh ter vpeljava ponovne uporabe odpadnih materialov. Bakterijska nanoceluloza (BC) zaradi skladnosti s tem konceptom ter njenih ugodnih lastnostih pridobiva vse več pozornosti za uporabo. Kljub ugodnim lastnostim pa se pojavlja pomanjkljivost na področju uporabe medicinskih aplikacij ter drugih tehnoloških področij, kjer je zahtevano protimikrobno delovanje, ki ga BC sama po sebi ne izkazuje. V raziskovalnem delu smo se tako osredotočili na modifikacijo BC s protimikrobnimi sredstvi. V ta namen smo si izbrali uporabo kvaternega hitozana (HTCC) ter odpad papirne industrije, ki vsebuje lignosulfonat (O-LS), kar je v skladu s konceptom trajnostnosti. Uporabljen HTCC je bil komercialno pridobljen kemijsko očiščen proizvod, medtem ko smo O-LS uporabili v obliki odpada papirne industrije podjetja Mondi, zaradi česar predvidevamo, da so poleg le-tega v sledovih prisotne še druge kemijske spojine. BC membrane, ki smo jih uporabili za modifikacijo so bile komercialno pridobljene, ki smo jih nadalje pripravili v dveh različnih oblikah – kot membrane in kot niti. Modifikacijo smo potrdili s sledečimi metodami: atenuirana popolna refleksija infrardeče spektroskopije s Fourierevo transformacijo (ATR-FTIR), rentgenska praškovna difrakcija (XRD), potenciometrična titracija, goniometrija, optična mikroskopija, vrstična elektronska mikroskopija (SEM), navzemanje vode (WU),
mehanska testiranja, protimikrobna testiranja. S pomočjo poglobljene analize smo potrdili spremembe v lastnostih BC v odvisnosti od strukture (membrana vs. nit) ter protimikrobno delovanje BC membran za S. aureus in S. epidermidis pri BC membrani modificirani z O-LS ter protimikrobno delovanje za S. aureus pri BC membrani modificirani s HTCC. Protimikrobno delovanje pri BC modificirani s HTCC je zagotovila kvaterna dušikova skupina v molekuli HTCC, pri BC modificirani z O-LS pa prisotnost fenolne spojine (prisotnost obeh smo potrdili z ATR-FTIR analizo). Z modifikacijo smo pridobili ultra čist, trajnostni material s protimikrobnim delovanjem, ki ima potencialno uporabno vrednost v medicini, kot tudi na drugih področjih kjer je tovrstna aktivnost zaželena.
Ključne besede: bakterijska nanoceluloza, hitozan, lignosulfonat, protimikrobne lastnosti
Objavljeno v DKUM: 08.09.2025; Ogledov: 0; Prenosov: 0
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5. Bralni kotiček na prostem kot rezultat projektnega dela v osnovni šoli : magistrsko deloMarko Bračič, 2025, magistrsko delo Opis: Projektno učno delo je sodoben pedagoški pristop, ki učencem omogoča aktivno vlogo pri reševanju izzivov iz vsakdanjega življenja. Pri tem razvijajo ključne kompetence, kot so ustvarjalnost, samostojnost, sodelovanje in odgovornost. Zunanji prostori šole ponujajo številne možnosti za učenje, vendar pogosto ostajajo neizkoriščeni.
Devetošolci so v okviru interesne dejavnosti, ki je potekala po načelih projektnega dela, oblikovali in izvedli projekt bralnega kotička v šolskem parku. Z mislijo na mlajše učence so izdelali ergonomsko oblikovano klop, knjigobežnico in lesen podest s cvetlično gredo ter uredili okolico. Ob tem so pridobivali tehnično znanje, spoznavali materiale, orodja in delovne postopke ter krepili občutek pripadnosti šolskemu prostoru. Čeprav je končni izdelek uspešno narejen, največjo vrednost predstavlja proces, ki je učencem omogočil izkustveno učenje, sodelovanje in aktivno sooblikovanje šolskega okolja.
Ključne besede: projektno učno delo, tehnika in tehnologija, knjigobežnica, bralni kotiček, osnovna šola
Objavljeno v DKUM: 16.07.2025; Ogledov: 0; Prenosov: 14
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6. Fizikalno-Kemijska in morfološka primerjava celuloze iz različnih virov : diplomsko deloMichela Sossi, 2025, diplomsko delo Opis: V diplomskem delu je bila narejena primerjava med celuloznimi materiali iz treh različnih virov, t. j. bombaža, lesa in bakterij glede na fizikalno-kemijske in morfološke lastnosti. Cilj raziskave je bil ugotoviti, kako izvor in način priprave materiala na osnovi celuloze vplivata na določene lastnosti, zlasti na sposobnost absorpcije barvil. Zastavljena hipoteza je predvidevala značilne razlike med vzorci glede na vir in pripravo. Za karakterizacijo materiala je bilo uporabljenih več metod, t.j. FTIR, SEM, optična mikroskopija, UV-VIS, gravimetrija, in goniometrija. Na podlagi rezultatov je bilo ugotovljeno, da vir in način priprave celuloze izrazito vpliva na morfološko strukturo, hidrofilnost in zmožnost adsorpcije barvila, pri čem je bilo potrjeno, da material iz bombažne celuloze je najbolj učinkovit in ima najvišjo kapaciteto adsorpcije barvila.
Ključne besede: bakterijska nanoceluloza, bombaž, karakterizacija, lastnosti, morfologija
Objavljeno v DKUM: 08.07.2025; Ogledov: 0; Prenosov: 23
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7. Metallisation of textiles and protection of conductive layers: An overview of application techniquesAlenka Ojstršek, Olivija Plohl, Selestina Gorgieva, Manja Kurečič, Urška Jančič, Silvo Hribernik, Darinka Fakin, 2021, pregledni znanstveni članek Opis: The rapid growth in wearable technology has recently stimulated the development of
conductive textiles for broad application purposes, i.e., wearable electronics, heat generators, sensors,
electromagnetic interference (EMI) shielding, optoelectronic and photonics. Textile material, which
was always considered just as the interface between the wearer and the environment, now plays
a more active role in different sectors, such as sport, healthcare, security, entertainment, military,
and technical sectors, etc. This expansion in applied development of e-textiles is governed by a
vast amount of research work conducted by increasingly interdisciplinary teams and presented
systematic review highlights and assesses, in a comprehensive manner, recent research in the field of
conductive textiles and their potential application for wearable electronics (so called e-textiles), as
well as development of advanced application techniques to obtain conductivity, with emphasis on
metal-containing coatings. Furthermore, an overview of protective compounds was provided, which
are suitable for the protection of metallized textile surfaces against corrosion, mechanical forces,
abrasion, and other external factors, influencing negatively on the adhesion and durability of the
conductive layers during textiles’ lifetime (wear and care). The challenges, drawbacks and further
opportunities in these fields are also discussed critically.
Ključne besede: metallization, conductive textiles, e-textiles, coatings techniques, protective coatings, durability
Objavljeno v DKUM: 16.06.2025; Ogledov: 0; Prenosov: 10
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8. Bioactive bacterial nanocellulose membranes for non-surgical debridement and infection prevention in burn wound healingUrška Jančič, Isabella Nacu, Liliana Vereştiuc, Fiorenza Rancan, Selestina Gorgieva, 2025, izvirni znanstveni članek Opis: Novel bioactive bacterial nanocellulose (BnC) membranes were developed for effective, non-surgical debridement and infection-prevention in burn wound healing. Membranes were modified in situ with carboxymethyl cellulose (CMC) and ex situ with the proteolytic enzyme bromelain (Br) and antimicrobial peptide nisin (N). Post-processing into stable cellulose nanocrystal dispersions (ζ = -26 mV), enables assembly of model films for demonstration of high, irreversible bromelain (95 %) and nisin (99.5 %) adsorption. The BnC-CMC and BnC-CMC-N membranes were in vitro cytocompatible for HaCaT cells and induced faster cell proliferation with cell viability exceeding 100 % after 24 h incubation. The innovative aspect of this study lies in the ex vivo evaluation using an advanced human skin explant model with induced burns, providing a realistic, physiologically relevant assessment of membrane performance. Ex vivo experiments indicated the cytocompatibility of the BnC-CMC membrane with no acute toxicity or skin irritation, while nisin presence resulted in moderate irritating effect. Notably, the BnC-CMC-Br membrane showed digestion of intercellular junctions in the epidermis, while not inducing acute toxicity and skin irritation. By leveraging this innovative ex vivo human skin model in novel BnC-based membranes testing, the study provides a crucial translational step, bridging in vitro assessments and clinical applications for burn wound treatment.
Ključne besede: bacterial nanocellulose, Bromelain, Nisin, Carboxymethyl cellulose, antimicrobial function, bioactive, burn wound treatment
Objavljeno v DKUM: 01.04.2025; Ogledov: 0; Prenosov: 13
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9. Bromelain and nisin: The natural antimicrobials with high potential in biomedicineUrška Jančič, Selestina Gorgieva, 2022, pregledni znanstveni članek Opis: Infectious diseases along with various cancer types are among the most significant public
health problems and the leading cause of death worldwide. The situation has become even more
complex with the rapid development of multidrug-resistant microorganisms. New drugs are urgently
needed to curb the increasing spread of diseases in humans and livestock. Promising candidates
are natural antimicrobial peptides produced by bacteria, and therapeutic enzymes, extracted from
medicinal plants. This review highlights the structure and properties of plant origin bromelain and
antimicrobial peptide nisin, along with their mechanism of action, the immobilization strategies, and
recent applications in the field of biomedicine. Future perspectives towards the commercialization of
new biomedical products, including these important bioactive compounds, have been highlighted.
Ključne besede: bromelain, nisin, bioactivity, antimicrobial agent, biomedicine, carrier
Objavljeno v DKUM: 27.03.2025; Ogledov: 0; Prenosov: 7
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10. Decontamination efficiency of thermal, photothermal, microwave, and steam treatments for biocontaminated household textilesBranko Neral, Selestina Gorgieva, Manja Kurečič, 2022, izvirni znanstveni članek Opis: With the outbreak of the COVID-19 pandemic, textile laundering hygiene has proved to be
a fundamental measure in preventing the spread of infections. The first part of our study evaluated
the decontamination efficiency of various treatments (thermal, photothermal, and microwave) for
bio contaminated textiles. The effects on textile decontamination of adding saturated steam into
the drum of a household textile laundering machine were investigated and evaluated in the second
part of our study. The results show that the thermal treatment, conducted in a convection heating
chamber, provided a slight reduction in efficiency and did not ensure the complete inactivation of
Staphylococcus aureus on cotton swatches. The photothermal treatment showed higher reduction
efficiency on contaminated textile samples, while the microwave treatment (at 460 W for a period of
60 s) of bio contaminated cotton swatches containing higher moisture content provided satisfactory
bacterial reduction efficiency (more than 7 log steps). Additionally, the treatment of textiles in the
household washing machine with the injection of saturated steam into the washing drum and a mild
agitation rhythm provided at least a 7 log step reduction in S. aureus. The photothermal treatment
of bio contaminated cotton textiles showed promising reduction efficiency, while the microwave
treatment and the treatment with saturated steam proved to be the most effective.
Ključne besede: household textiles, thermal treatment, decontamination, reduction efficiency
Objavljeno v DKUM: 24.03.2025; Ogledov: 0; Prenosov: 6
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