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Efikasno i jeftino čišćenje naftnih mrlja sa vode i tla kao i generisanje ogromnih količina tekstilnog otpada su goreći ekološki problemi koji zahtevaju hitno rešavanje. U pokušaju da se odgovori na oba izazova, proizveden je iglovani netkani sorbent od recikliranih vlakana jute iz industrije tepiha. Ispitan je uticaj površinske mase i debljine sorbenata na sorpcioni kapacitet za naftu u vodi i u nafti bez vode, sposobnost plutanja, sposobnost zadržavanja nafte i mogućnost ponovne upotrebe. Svi sorbenti su položili test plutanja. Površinska masa sorbenata i viskozitet testirane nafte i naftnih derivata (sirova nafta, dizel gorivo i dva motorna ulja) imaju snažan uticaj na sorpcioni kapacitet i sposobnost zadržavanja nafte. Sorbenti uglavnom zadržavaju do 50% svojih početnih sorpcionih kapaciteta nakon 5 ponovljenih ciklusa sorpcije što ukazuje da se mogu višekratno koristiti., Efficient and inexpensive cleanup of oil spills on water or land and huge generation of textile waste are burning environmental issues that are seeking urgent solutions. In an attempt to address both challenges, needle-punched non-woven sorbents (NWSs) based on recycled jute fibers from the carpet industry were manufactured. The influence of NWS area density and thickness on oil sorption capacity in water and oil without water, buoyancy, oil retention and reusability were studied. All NWSs passed the buoyancy test. The area density of NWSs and viscosity of tested oils (crude oil, diesel oil and two motor oils) strongly affect the oil sorption capacity and oil retention. NWSs mainly retain 50% of their initial oil sorption capacities after 5 repeated sorption cycles indicating that NWSs could be used several times.

The flammability of polyester textiles remains a significant challenge that must be overcome to allow their use in a variety of clothing and upholstery applications. In this work, water-based polyelectrolyte solutions composed of chitosan (CH) and pectin (P), as carbon-rich biomacromolecules, and mono ammonium phosphate (MAP) were deposited on enzyme/corona modified polyester via layer-by-layer (LbL) deposition. Four bilayers (BL) of 1% CH3/(1% P-30% MAP)4.2 renders the polyester fabric self-extinguishing in vertical flame testing. This recipe yields a 42.6% lower peak heat release rate and a nearly 40% reduction in the fire growth capacity, compared to uncoated polyester, as measured by micro cone calorimetry. The enzyme/corona modification, combined with the CH/(P-MAP) intumescent system, results in a very effective flame retardant treatment with few BL deposited.

Loose assemblies of cellulose fibers could be employed in the clean-up of oil spills, but the difficulty to separate them from the spill after use makes them impractical. In an effort to tackle this issue, a non-woven sorbent based on recycled jute fibers from the carpet industry was developed. To enhance the porosity and hydrophobicity/oleophilicity of the sorbent, carbonization in an inert atmosphere was carried out. A comparison in oil sorption performance between non-carbonized and carbonized sorbents was made by evaluating the oil capacity in a water medium, buoyancy, oil retention and reusability. Carbonization of sorbent resulted in more than doubled oil sorption capacity independent of oil viscosity. Oil viscosity did not affect the oil sorption capacity of non-carbonized sorbent. Carbonized sorbent showed superior buoyancy in water even after 24 hours, oil retention of approximately 60–80% after 3 hours and only 12–20% decline of oil sorption capacity after five repeated sorption/desorption trials. However, the ability of oiled non-carbonized sorbent to efficiently biodegrade in model compost (up to 45% weight loss after 10 weeks) makes it a sustainable candidate for oil spill clean-up.

Poor antimicrobial activity and lack of protection against UV irradiation are weaknesses of cottontextiles. In an attempt to impart superior antimicrobial and UV-protective properties to cotton, layer-by-layer deposition of chitosan and magnesium lignosulfonate, and in situ synthesis of silver (Ag)nanoparticles (NPs), was performed. Lignin, in a chitosan/lignin multilayer, simultaneously acts as a UVprotective macromolecule and natural reducing and stabilizing agent, allowing formation of Ag NPs. Fourbilayers of this coating is sufficient for fabrication of a chitosan/lignin/Ag-NP textile nanocompositetreatment with 50+ UV protection. 100% reduction of Gram-negative bacteria Escherichia coli, gram-positive bacteria Staphylococcus aureus, and yeast Candida albicans can be achieved with a 12-bilayercoating, when 20 mM silver nitrate solution and sodium borohydride are applied. On the other hand,four bilayers impregnated with Ag NPs, using 10 mM silver nitrate solution, provides sufficientantimicrobial activity independent of an added reducing agent. This treatment exhibits no inhibition ofhuman keratinocyte cells growth on the skin, indicating low cytotoxicity.

Novel cotton-based TiO2/Ag/TiO2 nanocomposites for wastewater treatment were developed by fine chemical synthesis path with the goal of coping with wastewater issues and environmental remediation. The photocatalytic performances of nanocomposites were tested during photodegradation processes of RB, AO7 and MR under simulated solar light. Double- and single-loaded nanocomposites were synthesized by a simple bottom-up approach implying in situ photoreduction of Ag+ ions on the surface of TiO2 NPs previously deposited on cotton fibers from colloids. The spherical-like colloidal TiO2 NPs (4.5 nm) and TiO2/Ag NPs (8 nm) and the formation of uniform TiO2/Ag and TiO2/Ag/TiO2 nano-coatings on cotton fibers were examined by TEM and FESEM. The reduction of Ag+ ions on TiO2 surface was undoubtedly proven by the appearance of SPR band of Ag NPs in UV/Vis spectra. Raman spectroscopy clearly confirmed the presence of anatase TiO2 in nanocomposites. Quantitative determination of TiO2 and Ag in nanocomposites was accomplished using EDX and ICP–OES. The cotton-based TiO2/Ag/TiO2 nanocomposite showed the highest photocatalytic efficiency (> 90%) and maintained its removal efficiency after three reuse cycles, indicated its exceptional photochemical ability. The initial idea of improved photocatalytic performances of a TiO2 NPs double-layer with immobilized Ag NPs was justified as the TiO2/Ag/TiO2 processed sample contributed additional binding sites for dye molecules. Considering that the photocatalytic activity of the cotton-based TiO2 and TiO2/Ag samples was practically imperceptible, it can be assumed that the synthesized Ag NPs act predominantly as electron traps in the double-loaded synthesized system.

Intensified oil exploitation accompanied with frequent oil spills having a detrimental impact on ecosystems are seeking efficient, environmentally and economically feasible solutions. In an attempt to develop an efficient, reusable, biodegradable and cheap sorbent for oil clean-up non-woven sorbents based on recycled jute post-industrial textile waste were fabricated. The influence of area density of non-woven sorbents and hydrophobicity of fibers on overall oil sorption performance was the focus of this research. All sorbents showed a good reusability after five sorption cycles and buoyancy in water even after 24 h independently of sorbent structure. The area density of sorbents and viscosity of studied oils (crude oil, diesel oil and two types of motor oils) highly affected the oil sorption capacity and oil retention. The sorbent with the lowest area density exhibited the best oil sorption performance. The esterification of jute with stearic fatty acid contributed to decrease in water uptake of sorbents but also to negligible change of oil sorption behavior indicating that the structure of the sorbent in this case plays a crucial role.

The aim of this study was to develop antimicrobial nanocomposite textile material comprising of Cu-based nanostructures synthesized on oxidized cotton fabric using Arctostaphylos uva-ursi (L.) Spreng., Ericaceae (bearberry leaves) as a green reducing agent for adsorbed Cu2+-ions. In order to provide sufficient number of carboxyl groups for complexation with Cu2+-ions a two-step oxidation process with NaIO4 and NaClO2 was carried out. The influence of NaIO4 concentration on content of carboxyl groups and Cu-based nanoparticles was studied by FTIR and AAS. HPLC analysis identified the gallic acid known as a reducing agent in bearberry leaves extract. FESEM and XRD analyses revealed that using bearberry leaves extract and gallic acid solution as reducing agents led to a formation of spherical Cu2O/CuO nanoparticles and CuO nanosheets, respectively. These nanoparticles and nanosheets provided excellent antibacterial activity against Gram-negative bacteria Escherichia coli and Gram-positive bacteria Staphylococcus aureus. Cytotoxicity on human keratinocyte cells was shown to depend on their copper content.

Creating multifunctional textiles using chemicals from renewable sources is challenging. In an effort to develop a sustainable and efficient multifunctional cotton treatment, a lignin-based multilayer nanocoating comprising magnesium lignosulfonate, chitosan, and monoammonium phosphate (MAP) was deposited using layer-by-layer assembly. A five bilayer coating adds 15.5 wt % to cotton and imparts fire extinguishing behavior and excellent UV and antimicrobial protection to the fabric. Just a two bilayer coating imparts sufficient self-extinguishing behavior to pass the standard vertical flame test. The combined influence of lignin as a char-forming and UV-protective macromolecule, chitosan as a char-forming biopolymer, and MAP acting as an antimicrobial agent (and a blowing agent and an acid source in an intumescent flame retardant system) results in a very powerful multifunctional textile treatment with very few layers of deposition.

In this study, C-doped TiO2 nanoparticles (C-TiO2) were prepared and tested as a photosensitizer for visible-light-driven photodynamic therapy against cervical cancer cells (HeLa). X-ray diffraction and Transmission Electron Microscopy confirmed the anatase form of nanoparticles, spherical shape, and size distribution from 5 to 15 nm. Ultraviolet–visible light spectroscopy showed that C doping of TiO2 enhances the optical absorption in the visible light range caused by a bandgap narrowing. The photo-cytotoxic activity of C-TiO2 was investigated in vitro against HeLa cells. The lack of dark cytotoxicity indicates good biocompatibility of C-TiO2. In contrast, a combination with blue light significantly reduced the survival of HeLa cells: illumination only decreased cell viability by 30% (15 min of illumination, 120 µW power), and 60% when HeLa cells were preincubated with C-TiO2. We have also confirmed blue light-induced C-TiO2-catalyzed generation of reactive oxygen species in vitro and intracellularly. Oxidative stress triggered by C-TiO2/blue light was the leading cause of HeLa cell death. Fluorescent labeling of treated HeLa cells showed distinct morphological changes after the C-TiO2/blue light treatment. Unlike blue light illumination, which caused the appearance of large necrotic cells with deformed nuclei, cytoplasm swelling, and membrane blebbing, a combination of C-TiO2/blue light leads to controlled cell death, thus providing a better outcome of local anticancer therapy.

The aim of this study was to fabricate novel antimicrobial nanocomposite materials by in-situ syntheses of Cu-based nanoparticles on PET and PA fabrics. The synthesis comprised three steps: (i) modification of PET and PA fabrics with biopolymer alginate in order to improve uptake of Cu2+-ions, (ii) sorption of Cu2+-ions from the solution of precursor salt and (iii) reduction of adsorbed Cu2+-ions in an alkaline solution of sodium borohydride. The influence of concentration of alginate and copper(II) sulphate solutions on Cu2+-ions uptake and total copper content after reduction was evaluated. The presence of Cu-based nanoparticles was proved by FESEM and XRD analysis. XRD analysis revealed the presence of CuO and Cu2O on the PET and PA fibers, respectively. Larger amounts of mostly agglomerated nanoparticles were detected on PET fiber surface than on the PA fiber surface. This observation is in line with results of AAS measurements confirming that the total content of Cu on the PET fabric was nearly 30% higher compared to PA fabric. Nanocomposite containing PET fibers provided excellent antimicrobial activity against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. On the other hand, nanocomposite comprising PA fibers ensured maximum antibacterial and fungistatic activities.

This work presents a new multilayered microfluidic platform, manufactured using a rapid and cost-effective xurography technique, for the detection of drug concentrations in sweat. Textile fabrics made of cotton and polyester were used as a component of the platform, and they were positioned in the middle of the microfluidic device. In order to obtain a highly conductive textile, the fabrics were in situ coated with different amounts of polyaniline and titanium dioxide nanocomposite. This portable microfluidic platform comprises at least three layers of optically transparent and flexible PVC foils which were stacked one on top of the other. Electrical contacts were provided from the edge of the textile material when a microfluidic variable resistor was actually created. The platform was tested in plain artificial sweat and in artificial sweat with a dissolved cytostatic test drug, cyclophosphamide, of different concentrations. The proposed microfluidic device decreased in resistance when the sweat was applied. In addition, it could successfully detect different concentrations of cytostatic medication in the sweat, which could make it a very useful tool for simple, reliable, and fast diagnostics.

The objective of this study was to develop novel antimicrobial nanocomposite material based on polypropylene (PP) non-woven fabric, biopolymer alginate and copper oxides nanoparticles. In order to introduce polar groups onto the surface of PP fibers necessary for binding of alginate, non-woven fabric was activated by corona discharge. Carboxylate groups of alginate were further utilized for binding of Cu2+-ions which were reduced with sodium borohydride as a conventional and ascorbic acid as a green reducing agent. Characteristic morphological and chemical changes induced by corona activation and alginate impregnation were confirmed by FTIR, XPS and FESEM analyses. AAS measurements showed that the amounts of generated nanoparticles depend on applied reducing agent and the concentration of precursor salt. XPS analysis suggested that nanoparticles were mixture of copper (I) and (II) oxides. XPS depth profiling gave an exceptional insight into chemical changes within the thin layer on the fiber surface and formation of certain interfaces induced by each treatment. All fabricated nanocomposites provided excellent antimicrobial activity against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. The cytotoxicity assay indicated that maximum amount of Cu2+-ions released from synthetized nanocomposite within 24 h was not cytotoxic to human keratinocyte (HaCaT) cells.

INTRODUCTION: Matrix-assisted laser desorption and ionization mass spectrometry (MALDI MS) is suitable for clinical applications because of its performances. On the other hand, if organic matrices are used, analysis of small molecules (mass <1000 Da) becomes difficult due to a high number and intensity of matrix –related signals. Certain physiologically important molecules, such as hormones, carbohydrates, drugs, and others, belong to the small molecule group. Application of TiO2 nanoparticles as substrates for surface-assisted laser desorption and ionization (SALDI) MS is, in these cases, promising tool. OBJECTIVES: To test the suitability of TiO2 nanoparticles with various sizes and shapes as substrates for SALDI MS of various classes of small biologically-relevant molecules. METHODS: The following TiO2 nanoparticles are prepared: colloidal nanoparticles (NPs, round, diameters of 5 nm), prolate nanospheroids (PNSs, 40-50 nm length) and nanotubes (NTs, approximately 100 nm long, 10 nm diameter). Samples (amino acids, steroid hormons, vitamins, carbohydrates) at various concentration were analyzed in positive and negative mode, whereas reproducibility and day-to-day repeatability was tested by ANOVA statistical analysis. RESULTS: By tested organic matrices, 63% of samples could not be detected, whereas by using any of nanoparticles, only 33% of analytes were not detectable. The spectra acquired with TiO2 nanoparticles, were characterized by lower number of well defined signals, which did not overlap with the signals from analytes. Analyte signals are simple, and the number of analyte-generated adducts is low when TiO2 substrates are used. Moreover, in some cases, also molecular ions could be detected. Generally, spectra were better reproducible when acquired with nanoparticles compared to organic matrices, as judged by the standard deviations in the signal-to-noise ratio (standard deviations are smaller when nanoparticles are used). In that sense, PNSs demonstrated

This study discusses the possibility of in situ synthesis of Cu-based nanoparticles (NPs) on cotton and viscose rayon fabrics previously modified with 1,2,3,4-butanetetracarboxylic acid (BTCA) of different concentrations, with the aim to obtain antibacterial protection. The changes in the chemical structure of the fibers caused by the modification with BTCA were assessed by FTIR spectroscopy. The higher the concentration of the applied BTCA, the larger the amounts of free carboxyl groups in both fabrics. AAS analysis showed that the samples modified with higher concentration of BTCA provided larger Cu2+-ions uptake and consequently, higher content of Cu after Cu2+-ions reduction. The presence of Cu-based NPs on the fabrics was confirmed by FESEM and EDS analyses. XRD analysis revealed that NPs appeared as a mixture of CuO and Cu2O. Synthesized NPs imparted excellent antibacterial activity to both fabrics against E. coli and S. aureus, including methicillin-resistant S. aureus.

This study discusses the possibility of fabrication of textile nanocomposites with antimicrobial activity against antibiotics-resistant bacterial strains and yeast. Modification of cotton fabric with oxalic acid solutions of different concentrations provided free carboxyl groups for binding of Cu2+ -ions from copper (II) sulfate solution which were further reduced with sodium borohydride in alkaline solution. An increase in the concentration of applied oxalic acid resulted in larger amounts of free carboxyl groups on the cotton fibers, Cu2+ -ions uptake and total amounts of Cu-based nanoparticles after reduction. XPS and XRD analyses suggested that nanoparticles mainly consisted of CuO with fractions of Cu2O. Fabricated textile nanocomposites ensured maximum reduction of Gram-negative E. coli ATCC 25922, E. coli NCTC 13846, E. coli ATCC BAA-2469, K. pneumoniae ATCC-BAA 2146 and P. aeruginosa ATCC 27853, Gram-positive bacteria S. aureus ATCC 25923 and S. aureus ATCC 43300 and yeast C. albicans ATCC 24433. Additionally, controlled release of Cu2+ -ions from fabrics into the physiological saline solution was obtained within 24 hours.

This study discusses the possibility of immobilization of colloidal TiO2 nanoparticles (NPs) onto poly(ε-caprolactone) (PCL) beads and foams that could be utilized for the removal of textile dyes from water by photodegradation. PCL foams were fabricated by environmentally friendly treatment of PCL beads in supercritical carbon dioxide. PCL beads and foams loaded with colloidal TiO2 NPs were used as photocatalysts for the removal of the textile dyes C.I. Acid Orange 7 and C.I. Basic Yellow 28 from aqueous solutions (10 mg L-1) under illumination that simulated sunlight. Unlike the PCL beads, the PCL foams provided complete discoloration of the dye solution within 24 h of illumination. The PCL foams also exhibited excellent floatability that was maintained for more than four weeks. Additionally, their photocatalytic activity was preserved within three repeated photodegradation cycles, indicating that the floating photocatalyst provided superior photocatalytic activity compared to the non-floating PCL beads., У овом раду је дискутована могућност имобилизације колоидних наночестица TiO2 на перлама или пени од поли(ε-капролактона) (PCL) које би се искористиле за уклањање боја за текстил из воде процесом фотодеградације. PCL пена је добијена еколошки прихватљивим третманом PCL перли у наткритичном CO2. PCL перле и пене су накнадно импрегниране колоидним наночестицама TiO2 и употребљене су као фотокатализатори за уклањање боја за текстил C.I. Acid Orange 7 и C.I. Basic Yellow 28 из воденог раствора (10 mg L-1) при осветљењу које симулира сунчеву светлост. За разлику од PCL перли, PCL пене су обезбедиле потпуно обезбојавање раствора боје током 24 h осветљавања. PCL пена је такође показала одличну способност плутања која је очувана дуже од четири недеље. Фотокаталитичка активност пена је задржана таком три поновљена циклуса испитивања фотодеградације што указује да овај плутајући фотокатализатор показује супериорну фотокаталитичку активност у поређењу са неплутајућим PCL перлама.

The fabrication of antimicrobial textile nanocomposite by in situ synthesis of Cu-based nanoparticles on cotton fabrics modified with different polycarboxylic acids was discussed in this study. In order to evaluate the influence of carboxyl group content on Cu2+-ions adsorption, their subsequent reduction with sodium borohydride and formation of Cu-based nanoparticles, cotton fabrics were modified with succinic, citric and 1,2,3,4-butanetetracarboxylic acids. It was shown that the larger the number of carboxyl groups in applied acid, the larger the content of free carboxyl groups on the fibers and consequently, the larger the Cu2+-ions uptake and total amounts of Cu-based nanoparticles. On the basis of the XPS and XRD measurements, it was suggested that synthesized nanoparticles were mixture of Cu2O and CuO. Fabricated nanocomposites provided maximum reduction of Gram-negative bacterium E. coli and Gram-positive bacterium S. aureus and controlled release of Cu2+-ions in physiological saline solution which are necessary prerequisites for infection prevention.

Photodynamic therapy implies a combined use of a photosensitizing medicament and low-intensity light to cause selective damage to the target tissue—tumor. As potential medicament, we use Ru(II)(dcbpy)2Cl2complex, and in order to achieve better photosensitization properties, the Ru complex was attached to the nano carrier—TiO2nanoparticles. Additionally, this nanocomposite system was encapsulated in the phospholipid vesicles, which could be classified as small unilamellar vesicles, based on the technique of production. The complex-release tests were performed under light illumination, at pH 5, characteristic for tumor cells` interior and compared with the release pattern at pH 7, characteristic for the serum, i.e. physiological solution.

A comprehensive study of the removal of selected biologically active compounds (pharmaceuticals and pesticides) from different water types was conducted using bare TiO2nanoparticles and TiO2/polyaniline (TP-50, TP-100, and TP-150) nanocomposite powders. In order to investigate how molecular structure of the substrate influences the rate of its removal, we compared degradation efficiency of the initial substrates and degree of mineralization for the active components of pharmaceuticals (propranolol, and amitriptyline) and pesticides (sulcotrione, and clomazone) in double distilled (DDW) and environmental waters. The results indicate that the efficiency of photocatalytic degradation of propranolol and amitriptyline was higher in environmental waters: rivers (Danube, Tisa, and Begej) and lakes (Moharač, and Sot) in comparison with DDW. On the contrary, degradation efficacy of sulcotrione and clomazone was lower in environmental waters. Further, of the all catalysts applied, bare TiO2and TP-100 were found to be most effective in the mineralization of propranolol and amitriptyline, respectively, while TP-150 appeared to be the most efficient in terms of sulcotrione and clomazone mineralization. Also, there was no significant toxicity observed after the irradiation of pharmaceuticals or pesticides solutions using appropriate catalysts on rat hepatoma (H-4-II-E), mouse neuroblastoma (Neuro-2a), human colon adenocarcinoma (HT-29), and human fetal lung (MRC-5) cell lines. Subsequently, detection and identification of the formed intermediates in the case of sulcotrione photocatalytic degradation using bare TiO2and TP-150 showed slightly different pathways of degradation. Furthermore, tentative pathways of sulcotrione photocatalytic degradation were proposed and discussed. Kinetics, toxicity and intermediates assessment of biologically active compounds (pesticides and pharmaceuticals) in environmental waters.

In a series researches so far, it has been shown that TiO2 nanoparticles have become the focus of intensive exploration in the field of photocatalysis, as a consequence of their unique properties and potential applications. In order to improve photocatalytic and functional properties of TiO2 nanoparticles, different methods should be used. One of the most effective approaches is capping of nobel metal (Pt, Ag, Au) clusters on nanoparticle surface. Namely, metal clusters act as electron traps and they promote interfacial charge- -transfer processes and reduce undesirable recombination processes on TiO2 nanoparticle surface. As a consequence, photocatalytic efficiency of the system should be improved. The cotton fabric modified by TiO2/Ag nanoparticles was synthesized by in situ photoreduction of Ag+-ions on alanine modified TiO2 colloidal nanoparticles previously deposited onto cotton fabric. Adsorption of Ag+-ions on TiO2 nanoparticle surface was improved by addition of alanine amino-acid. As a result, separation of photoinduced charges is preferred and recombination process is significantly reduced. In order to further improve the efficiency of the system, methyl alcohol was employed as hole-scavenger. Obtained results confirmed the presence of TiO2/Ag nanoparticles across the surface of cotton fabric (SEM), as well as successful fabrication of metallic Ag on investigated fabric (XRD). Interaction between alanine modified TiO2 and Ag nanoparticles was studied by FTIR, while structural properties of synthesized samples were investigated by Raman spectroscopy. The photocatalytic performance of TiO2/Ag nanoparticles modified cotton fabric was tested in the process of photodegradation of organic dyes under simulated solar light: Rhodamine B, Acid Orange 7 and Methyl Red.

Doktorska disertacija je imala za cilj sintezu i karakterizaciju nanokompozita koji poseduju antimikrobna svojstva inovativnom metodom in situ fotoredukcije Ag+-jona na površini nanokristala TiO2 različitih oblika, prethodno deponovanih na tekstilnim materijalima. Ovakav pristup sintezi nanokompozitnih tekstilnih materijala je po prvi put realizovan u okviru ove teze..., This doctoral thesis relates to the synthesis and characterization of advanced nanocomposites which exhibit antimicrobial activity and UV protective properties. For the synthesis an innovative method based on in situ photoreduction of Ag+-ions onto the surface of differently shaped TiO2 nanocrystals, being in the form of either spherical nanoparticles or nanotubes, deposited on different textile materials was applied. Such synthesis route for the formation of textile nanocomposites has been realized for the first time in the context of this thesis...

This study discusses the possibility of in situ photoreduction of Ag+-ions on the surface of titania nanotubes (TNTs) deposited on the cotton and cotton/PET fabrics in the presence of amino acid alanine and methyl alcohol. TNTs were synthetized by hydrothermal method. The proposed interaction between titania, alanine and Ag+-ions was based on the results obtained by FTIR measurements. In order to enhance the binding efficiency between TNTs and fibers, the fabrics were previously impregnated with polyethyleneimine. The presence of TNT/Ag nanocrystals on the surface of fibers was proved by SEM, AAS, XRD and XPS. Larger amount of silver was detected on the cotton fabric. Fabricated TiO2/Ag nanocrystals provided maximum reduction of bacteria E. coli which was preserved after five washing cycles despite significant release of silver. The perspiration fastness tests indicated that silver release did not depend on pH. The presence of TNT/Ag nanocrystals imparted maximum UV protection to fabrics.

This study discusses the effect of corona pre-treatment at atmospheric pressure and subsequent loading of colloidal TiO2 nanoparticles on the biodegradation behavior of cotton fabric. Biodegradation performance of the control and finished samples was evaluated by standard soil burial tests in predetermined periods of 3, 9 and 18 days. Color and breaking strength measurements were utilized for assessment of biodegradation progress. Morphological and chemical changes induced by biodegradation were analysed by SEM and FT-IR analyses, respectively. Colorimetric, morphological and chemical changes induced by the biodegradation process were slightly less prominent on corona pre-treated cotton fabric impregnated with TiO2 nanoparticles compared to corona treated and control cotton fabric. Although the breaking strength of all samples significantly decreased after 18 days of soil burial, this decline was the least evident on the sample impregnated with TiO2 nanoparticles. However, taking into account the extent of these differences, the influence of TiO2 nanoparticles on biodegradation rate of cotton fabric, which underwent a combined treatment corona/impregnation with TiO2 nanoparticles, could be considered as insignificant. These results confirm that chemical modification of cotton fabrics with plasma and subsequent loading of TiO2 still maintained sustainability of cellulose fibres.

A simple bottom-up method for the preparation of novel and very efficient photocatalytic nanocomposite system based on carbonized form of polyaniline (PANI) and colloidal TiO2 nanocrystals has been developed. The carbonized PANI/TiO2 nanocomposites were synthesized in a two-step procedure. Firstly, non-carbonized PANI/TiO2 nanocomposites were synthesized by the chemical oxidative polymerization of aniline (ANI) with ammonium peroxydisulfate, in the presence of colloidal TiO2 nanoparticles (TiO2 NPs) (d 4.5 nm). Initial [TiO2 NANI] mole ratios were 20, 50, and 80. In the second step, following the polymerization process, the carbonization of PANI/TiO2 nanocomposites was performed by thermal treatment in an inert atmosphere at 650 degrees C. The morphological and structural properties of the carbonized nanocomposites were studied using transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray powder diffraction (XRD) and Raman spectroscopy. The accomplishment of complete carbonization of PANI in PANI/TiO2 nanocomposites was confirmed by Raman spectroscopy. The appearance of anatase and rutile crystal forms in TiO2 NPs upon carbonization, with mass ratio depending on the initial molar ratio of ANI and TiO2 NPs was revealed by XRD measurements, TEM, SEM and Raman spectroscopy. The photocatalytic activities of carbonized PANI/TiO2 nanocomposites were evaluated following the photocatalytic degradation processes of Rhodamine B and Methylene blue. Carbonized PANI/TiO2 nanocomposites showed higher photocatalytic efficacy compared to bare TiO2 NPs and non-carbonized PANI/TiO2 nanocomposites. The porosity and surface structure of carbonized PANI/TiO2 nanocomposites, as well as crystalline structure of TiO2, affect photocatalytic activity of nanocomposites. (C) 2017 Elsevier B.V. All rights reserved.

Depression is a disease of an abnormal brain energy metabolism also marked with increased apoptosis in specific brain regions. Mounting evidence indicates that the mitochondrial oxidative phosphorylation and apoptosis are novel targets for the actions of estrogen receptors (ERs). In this study, we examined the effects of antidepressant (AD) fluoxetine (FLU) treatment on the mitochondria] ER alpha (ER alpha), ER beta (total and phospho-pER(beta) and their association with cytochrome c (cyt oxidase activity and apoptotic Bcl2/Bax-molecules in the hippocampal mitochondria of chronically isolated (CPSI) female and male rats depicting depression. Impaired behaviour induced by CPSI was followed by decreased corticosterone (CORT) in both sexes and downregulation of cyt c oxidase in males. CPSI did not affect the ERa in either of sexes, but it decreased mitochondrial ER beta and increased pER beta in both sexes. Stress-reduced ER beta is associated with a decrease in mitochondrial energetic processes in males and with apoptotic mechanisms in females. FLU normalized behaviour in both sexes and increased cyt c oxidase in females. FLU elevated ERa in males, increased ER beta and decreased pERB in both sexes. The AD-induced alterations of ER beta paralleled with bioenergetics and pro-survival pathways in females. In conclusion, sex-unspecific regulation of ER beta by the stress and by AD and its differential convergence with bioenergetics and apoptotic pathways in females and males implies its role as a vulnerability factor in the stress response and emphasizes mitochondrial ER beta-dependent pathways as an important gateway of ADs action, at least in females. (C) 2017 Elsevier B.V. All rights reserved.

We studied the colloidal TiO2 nanoparticles as a carrier for controlled delivery of the ruthenium complex to the melanoma cell line. The system demonstrated slower complex release upon visible and increased release rate upon UV light illumination. Accordingly, the light-dependent cytotoxicity of the system was demonstrated on amelanotic melanoma cancer line. The cell death is enhanced by UV and reduced by red light in the presence of investigated nanocomposite system. Both components of the system may act as photosensitizers, by generating reactive oxygen species, which promote cell death. Thus, the system might act dually, as photodynamic therapeutic agent and as the light tunable system for metallo-drug delivery and it might be of interest for development of new more efficient drug delivery approaches by using a light as external stimulus. (C) 2017 Elsevier B.V. All rights reserved.

Approximately 13 million of new cancer cases are diagnosed every year, and the mortality rate is projected to rise, with an estimation of 13.1 million deaths in 2030 [1]. The conventional cancer treatments such as chemotherapy, radiotherapy and surgery suffer from serious drawbacks that hamper patients’ healing and recovery: radiation therapy is limited by the cumulative radiation dose,chemotherapy is frequently associated with systemic side-effects, while rather high recurrence rate is associated with surgical resection of tumors. Photodynamic therapy, which implies combined use of a photosensitising medicament and low-intensity light to cause selective damage to the target tissue, is an alternative tumor-ablative, function-sparing and costeffective oncologic approach [2]. Usually, medicaments are delivered to diseased tissues by different types of nanoparticle (NP) carriers. The light-induced medicament activation is based on the intrinsic optical properties of a medicament carrier and a medicament itself. In most cases, a NP-based medicament carrier or a medicament itself acts as photosensitizers [PSs], by triggering the free radical reactions in cells leading eventually to the cell death. The most PSs are characterized by high lipophilicity, and due to that, different encapsulation strategies have been explored to protect the hydrophobic PS from the aqueous environment. We used TiO2 NPs for medicament carriers because of their availability, non-toxicity, stability and possibility of surface modification. On the other hand, Ru(II)(dcbpy)2Cl2 complex, that belongs to the second generation of metallodrugs, can be easily attached to the TiO2 surface via carboxyl groups [3], while central metal ion remains free for the interaction with biomolecules. Additionally, this system has genotoxic effect on melanoma cells [4]. The aim of the present study was to modify the nanocomposite system (NCS) based on the Ru complex and TiO2 NPs in order to increase the cellular uptake

The present paper deals with removal and photocatalytic degradation of the textile dyes by TiO2 nanoparticles immobilized onto chitosan-based microparticles. The microparticles composed of chitosan (Ch) and poly(methacrylic acid) (PMA) were fabricated for the first time by inverse suspension polymerization. They were utilized for colloidal TiO2 nanoparticles immobilization, synthetized by acidic hydrolysis of TiCl4. To evaluate the potential application of Ch/PMA/TiO2 microparticles for treatment of textile wastwaters, their photocatalytic activity was examined by degradation assessment of three different groups of anionic azo dyes in aqueous solutions under solar light simulating source. FTIR analysis revealed that Ch and PMA were incorporated in the polymer network. SEM and optical microscopy confirmed their spherical shape. Under illumination, Ch/PMA/TiO2 microparticles completely removed dyes C.I. Acid Orange 7, C.I. Acid Red 18, C.I. Acid Blue 113, C.I. Reactive Black 5, C.I. Direct Blue 78, while removal degree of C.I. Reactive Yellow 17 was 75%. It was found that pH had significant influence on the photocatalytic activity of Ch/PMA/TiO2 microparticles. Increase of solution pH from acidic to alkaline, lead to decrease in photodegradation rate of C.I. Acid Orange 7 during the first hours of illumination. After three illumination cycles, removal degree of C.I. Acid Orange 7 was maintained at remarkably high level (95% at pH 5.60 and 100% at pH 2.00 and 8.00), indicating that microparticles could be reused without significant loss of photocatalytic efficiency.

Photo-responsive drug release systems are promising for drug delivery applications due to many benefits compared to conventional chemotherapy such as targeted, controlled release of a drug and reduced toxicity to healthy tissues. In this work, we report synthesis of the nanocomposite system based on carrier TiO2 nanoparticles and potential anticancer ruthenium complex, with light controllable release properties. Nanocomposite system showed biological activity and induced the generation of free radicals, which are implied in the efficient cell killing. The drug release tests demonstrated sustained release of the transition metal complex from the surface implying the potency for the controlled drug delivery system. Taking into account photoactivity of the Ru-complex, in the next step we have investigated the influence of green light on the rate of the complex release, and the results showed dependence of the Ru-complex release from the surface of TiO2 nanoparticles on the applied laser energy. Therefore, these characteristics make this nanocomposite system promising for the photo-responsive chemotherapy.

Nanofibrous polyanilines (PANIs) were synthesized by several oxidative polymerization pathways that have in common the presence of excess oxidant(s) (ammonium peroxydisulfate and its mixture with hydrogen peroxide), the absence of added acid, and the absence of external template (self-assembly process). Conducting forms of the synthesized PANI nanofibers (re)doped with various acids were further used as precursors for carbonization process to obtain nanofibrous carbonaceous materials (Carb-PANIs). Morphology, molecular structure, surface properties and electrical characteristics of PANI nanofibrous precursors and their carbonized counterparts were studied by scanning electron microscopy, Raman spectroscopy, by measurements of zeta-potential and determination of isoelectric points, as well as by measurements of electrical conductivity. (C) 2016 Elsevier B.V. All rights reserved.

The present paper deals with removal and photocatalytic degradation of the textile dyes by TiO2 nanoparticles immobilized onto chitosan-based microparticles. The microparticles composed of chitosan (Ch) and poly(methacrylic acid) (PMA) were fabricated for the first time by inverse suspension polymerization. They were utilized for colloidal TiO2 nanoparticles immobilization, synthetized by acidic hydrolysis of TiCl4. To evaluate the potential application of Ch/PMA/TiO2 microparticles for treatment of textile wastwaters, their photocatalytic activity was examined by degradation assessment of three different groups of anionic azo dyes in aqueous solutions under solar light simulating source. FTIR analysis revealed that Ch and PMA were incorporated in the polymer network. SEM and optical microscopy confirmed their spherical shape. Under illumination, Ch/PMA/TiO2 microparticles completely removed dyes C.I. Acid Orange 7, C.I. Acid Red 18, C.I. Acid Blue 113, C.I. Reactive Black 5, C.I. Direct Blue 78, while removal degree of C.I. Reactive Yellow 17 was 75%. It was found that pH had significant influence on the photocatalytic activity of Ch/PMA/TiO2 microparticles. Increase of solution pH from acidic to alkaline, lead to decrease in photodegradation rate of C.I. Acid Orange 7 during the first hours of illumination. After three illumination cycles, removal degree of C.I. Acid Orange 7 was maintained at remarkably high level (95% at pH 5.60 and 100% at pH 2.00 and 8.00), indicating that microparticles could be reused without significant loss of photocatalytic efficiency. (C) 2016 Elsevier Ltd. All rights reserved.

Photo-responsive drug release systems are promising for drug delivery applications due to many benefits compared to conventional chemotherapy such as targeted, controlled release of a drug and reduced toxicity to healthy tissues. In this work, we report synthesis of the nanocomposite system based on carrier TiO2 nanoparticles and potential anticancer ruthenium complex, with light controllable release properties. Nanocomposite system showed biological activity and induced the generation of free radicals, which are implied in the efficient cell killing. The drug release tests demonstrated sustained release of the transition metal complex from the surface implying the potency for the controlled drug delivery system. Taking into account photoactivity of the Ru-complex, in the next step we have investigated the influence of green light on the rate of the complex release, and the results showed dependence of the Ru-complex release from the surface of TiO2 nanoparticles on the applied laser energy. Therefore, these characteristics make this nanocomposite system promising for the photo-responsive chemotherapy.

This study discusses the possibility of using corona pre-treated polypropylene (PP) non-woven fabric as a support for immobilization of colloidal TiO2 and Ag nanoparticles in order to remove dye C.I. Acid Orange 7 from aqueous solution. Dye removal efficiency by sonocatalysis, photocatalysis and sonophotocatalysis was evaluated on corona pre-treated fabric loaded with TiO2 nanoparticles, corona pre-treated fabric double loaded with TiO2 nanoparticles and corona pre-treated fabrics loaded with TiO2 nanoparticles before and after deposition of Ag nanoparticles. In addition, the stability of PP non-woven fabric during these processes was investigated. The substrates were characterized by SEM, EDX and AAS analyses. The change of the dye concentration was evaluated by UV-VIS spectrophotometry. Unlike sonocatalysis and photocatalysis, complete dye removal from both solution and non-woven fabric was obtained already after 240-270 min of sonophotocatalysis. Corona pre-treated PP non-woven fabric loaded with Ag nanoparticles prior to deposition of TiO2 nanoparticles provided excellent degradation efficiency and superior reusability. Sonophotocatalytic degradation of dye in the presence of all investigated samples was the most prominent in acidic conditions. Although this nanocomposite system ensured fast discoloration of dye solution, TOC values of water measured after sonophotocatalysis were not satisfactory because of PP degradation. Therefore, it is suggested to include TOC evaluation in each case study where different supports for TiO2 nanoparticles are used since these nanoparticles may guarantee the dye removal from solution but the stability of support could be problematic causing even more serious environmental impact. (C) 2014 Elsevier B.V. All rights reserved.

This study presents contact experiments and filtration tests with nanofibre membranes containing TiO2 nanoparticles in view of effluent treatment. The first part of this study focuses on the removal of dissolved organic matter, more specifically humic acids. Removal of humic acids from secondary wastewater treatment plant effluent as well as from synthetic water solutions was tested. Also the bactericidal effect of the TiO2 functionalised nanofibre membranes was examined. Contact experiments with TiO2 functionalised membranes showed removal of humic acids (83% degradation after 2 h) and Staphylococcus aureus (4.5 log(10)/100 ml after 6 h). Also the possibility of using (TiO2 functionalised) nanofibre membranes for effluent filtration in view of water reuse, was examined. Such secondary effluent filtration tests improved water quality as a reduction in turbidity (69%), humic acids (37%) and bacterial activity (76%) was observed. It can be concluded that nanofibre membranes could be used as a high-flux filtration technique for effluent recuperation.

An interpenetrating polymer network (IPN) based on the sodium alginate (A) and partially neutralized poly(methacrylic acid) (MAA) was prepared by free radical polymerization followed by additional cross-linking of sodium alginate with calcium ions. Obtained material (A/MAA IPN) was characterized by FTIR spectroscopy, thermogravimetric analysis, scanning electron microscopy, and rheological measurements. Swelling behavior of synthetized IPN has been also investigated. TiO2 nanoparticles (TiO2 NPs) were immobilized onto A/MAA IPN by dip-coating method and obtained TiO2/IPN nanocomposite was used for removal of the methylene blue (MB) from aqueous solution. The photodegradation (under illumination) and sorption (in the dark) processes for dye removal were monitored through decrease of dye concentration in the solution by UV/VIS spectrometer. The TiO2/IPN nanocomposite sorbed approximately 93% of the MB from a 10 mg L-1 MB solution in the dark, but no degradation occurred. Likewise, more than 93% of dye was removed after 8 h of illumination. However, after 24 h of illumination, the samples were discolored indicating that dye molecules were successfully degraded. Thus, the TiO2/IPN nanocomposite could be utilized in the photodegradation-sorption process for the abatement of pollutants in water. POLYM. ENG. SCI., 55:2511-2518, 2015.

Recently, many efforts have been made to efficiently impregnate different textile materials with metal and metal oxide nanoparticles in order to provide antimicrobial, UV protective or self-cleaning properties. Evidence of their environmental risks is limited at this point. The aim of this study was to explore the influence of Ag and TiO2 nanoparticles on biodegradation of cotton fabrics. Biodegradation behavior of cotton fabrics impregnated with Ag and TiO2 NPs from colloidal solutions of different concentrations was assessed according to standard test method ASTM 5988-03 and soil burial test. Degradation of cotton fabrics was also evaluated by enzymatic hydrolysis with cellulase. The morphology of fibers affected by biodegradation was analyzed by scanning electron microscopy (SEM). In order to get better insight into biodegradation process, dehydrogenase activity of soil has been determined. Ag and particularly TiO2 nanoparticles suppressed the biodegradation of cotton fabrics. The dehydrogenase activity of soil with cotton fabrics impregnated with TiO2 nanoparticles was the weakest. Severe damage of cotton fibers during the biodegradation process was confirmed by SEM.