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For the purpose of this investigation, a sensitive, and rapid inductively coupled plasma mass spectrometry (ICP-MS) spectroscopy was applied in determination of antimicrobialy active elements of the core/shell microcapsules. Microcapsules of different sizes (120 and 450 μm) and chemical composition were prepared with zinc and sodium alginate in the shell (and with or withouth chitosan), as well as filled with the antimicrobial silver in the core. After preparation, and prior the analysis, the samples were digested in an microwave oven using 55.55% v/v HNO3 and 44.45% v/v H2O2. Digested samples were transferred to ICP-MS and analysed with aim to monitor the levels of zinc and silver, both being powerful antimicrobial agents. The results show that there is a significant difference in levels of antimicrobial metals between samples prepared with and without chitosan. Whilst Zn levels appeared marginally higher (up to 20 %) in the group of samples prepared without chitosan, compared with the group with it, the Ag content showed larger overall variability (more than 72%). Particularly, smaller microcapsules (120 μm), had the following elemental composition of antimicrobial metals: 98.32 μg/g of Ag and 106.75 μg of Zn. In contrast, three times larger microcapsules (450 μm) contained two times higher amounts of silver (190.98 μg/g) and only 20 % higher amounts of zinc (121.35 μg/g). Nevertheless, after performing the leaching experiments, obtained results proved that the amounts of antimicrobial elements were high enough for efficient antimicrobial activity of newly prepared microcapsules. Therefore such samples can be efficiently applied as antimicrobial coatings on many different items.

World Health Organization has recognized the problem of antimicrobial resistance as one of the most important issues in world health protection. Due to the increasing resistance of harmful bacteria and other microorganisms to conventional drugs, it is necessary to develop new solutions for medical textile materials. The antimicrobial properties of silver ions are intensively investigated in a form of silver ions and silver nanoparticles, so their application on medical textile materials is very important. Therefore, this study aimed to functionalize textile surfaces with antimicrobial microcapsules filled with antimicrobial substances. The characterization tests were performed by ultraviolet and visible spectrometry on samples containing silver in microcapsules in both nanoparticle and ionic forms. Testing of the samples was performed on ready-made microcapsules obtained from sodium alginate, which contained silver in their core. In contrast, the outer shell was made of zinc sulfate 7-hydrate. The encapsulation method using the Buchi Encapsulator B-390 encapsulator was used to obtain these microcapsules. For characterization purposes, the test was performed on a two-beam Lambda 20 instrument, manufactured by Perkin Elmer from the United States. The test was performed in the ultraviolet and visible range, in the range of 190 to 900 nm. The test was performed in an aqueous medium in which the microcapsules released silver. The obtained test results will enable the determination of the concentration of silver released over time from microcapsules in an aqueous medium, and based on the obtained results, the antimicrobial properties of silver ions will be estimated based on the released quantities that are efficient for removal of certain strains of microorganisms on textile medical materials.

World Health Organization has emphasized that the problem of antimicrobial resistance is one of the most important issues in protection of the global population health. Moreover, the WHO has encouraged researchers and scientist to strive in detecting more powerful and more innovative solutions in producing antimicrobial materials. Therefore this presentation will bring the state-of-the-art initiatives that enable efficient functionalization of antimicrobial polymer surfaces. The most powerful activity against microorganisms that are resistant to antibiotics are nanoparticles of metals and metalo oxides. Therefore, this study will introduce to the scientific community the methodologies and procedures that we use for functionalization of 3D printed polymers, as well as textile surfaces. Such coatings can contain pure nanoparticles, or their combination with other active species. Moreover, in specific cases the antimicrobial substances can be filled materials that will enable their slow release into the environment. Lastly, the presentation will show the most important characterization methodologies needed for successful monitoring of the antimicrobial reagents. To conclude, the presentation will summarize the state-of-the-at technologies used in functionalization of antimicrobial polymers, to be shared in the scientific community for the benefit of all.

This paper reports a study on four historical samples from 19th century originating from Croatia, Europe, made of silver plated and gilded copper alloys. The investigation was carried out by chromatographic, spectroscopic, and microscopic techniques. Corrosion was identified in all samples by scanning electron microscope-energy dispersive spectroscopy (SEM-EDS), although the samples were in well-preserved states. EDS has given the following average composition of elements Ag (82.99, 4.74, 6.34, and 15.54wt% in samples 1–4, respectively), Au (17.01wt%in sample 1), and Cu(0, 95.26, 93.66, and 84.46 wt% in samples 1–4, respectively) for theouter layers of the samples.The exactsample elemental composition was determined by inductively coupled plasma optical emission spectroscopy (ICP-OES): 0.12, 0.22, 0.68, and 1.20wt% Ag in samples 1–4, respectively and 0.02wt%Au in sample 2, all on Cu alloyswith impurities of Fe, Mn, Ni, Pb, Sb, Si, Sn, and Zn (in quantities 0.05–1.48 wt%). Preliminary detection of metals was performed by thin-layer chromatography. Results of determined chemical composition were consistent with similar investigations, since silver-plated and gilded Cu alloyswere thematerials used in the production of similar samples through the history.

U radu je prikazano ispitivanje sadržaja mikrokapsula alginata punjenih nanočesticama srebra koje pokazuju izuzetno snažna antimikrobna i antibakterijska svojstva, a koje su pogodne za nanašanje na tekstilne materijale i funkcionaliziranje površine. Nanočestice srebra imaju anti-bakterijsko djelovanje na širok spektar Gram-pozitivnih i Gram-negativnih bakterija, uključujući spojeve rezistentne na antibiotike. Imaju veliku primjenu zbog svoje kemijske stabilnosti, kata-litičke aktivnosti, i visoke vodljivosti te izuzetnu antimikrobnu aktivnost zbog visokog omjera površine i volumena, što im osigurava bolji kontakt s mikroorganizmima. Metode inkapsulacije koriste se u tekstilnoj, farmaceutskoj i kozmetičkoj industriji kako bi dostavile biološki aktivne supstance na željena mjesta. Dostupnost novih aktivnih nanočestica otvorila je mogućnosti razvoja novih matrica i primjena koje se mogu koristiti u razvoju raznih proizvoda, a inkapsuli-ranje je relativno nova tehnologija koja omogućuje čuvanje, stabilnost i sporo otpuštanje akti-vnih tvari. Materijale za oblikovanje mikrokapsula uglavnom čine ugljikohidrati (škrob, celuloza, gume), proteini (proteini mlijeka - kazeini i proteini sirutke, gluten, želatina) i lipidi (masne ki-seline, alkoholi, gliceridi, voskovi, fosfolipidi) ili njihova kombinacija. Mikrokapsule postaju sve prisutnije u funkcionalizaciji tekstilnih polimera. Tehnike inkapsuliranja bioaktivnih sastojaka obuhvaćaju koacervaciju, mikrokapsuliranje raspršivanjem u struji toplog zraka, mikrokapsuli-ranje fluidiziranih čestica, mikrokapsuliranje ekstruzijom i superkritičnim fluidima, emulgira-njem i kokristalizacijom. U ovom radu su priređene mikrokapsule ispitivane metodom tanko-slojne kromatografije kako bi se odredio sadržaj srebra na uzorcima. Kromatografska metoda pokazala se kao vrlo brza, učinkovita i ekonomski isplativija metoda od mnogih instrumentalnih metoda te se preporuča za korištenje u mnogim ispitnim laboratorijima., This work presents thin layer chromatographic determination of the content of alginate micro-capsules filled with silver nanoparticles that exhibit extremely strong antimicrobial and antiba-cterial properties, which are suitable for application on textile materials and their surface fun-ctionalization. Silver nanoparticles have anti-bacterial effects on a wide range of Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains. They are widely used beca-use of their chemical stability, catalytic activity, and high conductivity, as well as their excepti-onal antimicrobial activity due to their high surface-to-volume ratio, which provides them with better contact with microorganisms. Encapsulation methods are used in the textile, pharmace-utical and cosmetic industries to deliver biologically active substances to desired places. The availability of new active nanoparticles has opened up opportunities for the development of new matrices and applications that can be used in the development of various products, and encapsulation is a relatively new technology that enables the storage, stability and slow rele-ase of active substances. Materials for forming microcapsules are mainly carbohydrates (starch, cellulose, gums), proteins (milk proteins - caseins and whey proteins, gluten, gelatin) and lipids (fatty acid-line, alcohols, glycerides, waxes, phospholipids) or a combination thereof. Microcapsules are becoming increasingly present in the functionalization of textile polymers. Techniques for encapsulating bioactive constituents include co-conservation, micro-encapsu-lation by hot-air flow, micro-encapsulation of fluidized particles, micro-encapsulation by extru-sion and supercritical fluids, emulsification and cocrystallization. In this work, microcapsules were investigated by thin layer chromatography to determine the silver content of the samples. The chromatographic method has proven to be a very fast, efficient and cost-effective method advantageous over many other instrumental methods and can be threfore recommended for usage in many test laboratories.