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Biofouling is a major concern to the maritime industry. Biofouling increases fuel consumption, accelerates corrosion, clogs membranes and pipes, and reduces the buoyancy of marine installations, such as ships, platforms, and nets. While traditionally marine installations are protected by toxic biocidal coatings, due to recent environmental concerns and legislation, novel nanomaterial-based anti-fouling coatings are being developed. Hybrid nanocomposites of organic-inorganic materials give a possibility to combine the characteristics of both groups of material generating opportunities to prevent biofouling. The development of bio-inspired surface designs, progress in polymer science and advances in nanotechnology is significantly contributing to the development of eco-friendly marine coatings containing photocatalytic nanomaterials. The review mainly discusses photocatalysis, antifouling activity, and formulation of coatings using metal and metal oxide nanomaterials (nanoparticles, nanowires, nanorods). Additionally, applications of nanocomposite coatings for inhibition of micro- and macro-fouling in marine environments are reviewed.

Nanotechnology is one of the emerging technique of preservation not only in food industry but in other fields we are aware of Various new and innovative applications about nanotechnology and nanoscience has been developed in the food industry.Those applications are utilized for food sector, agriculture , horticulture, food science namely food production, food processing, nano-packaging, nanosensors and fruits and vegetable packaging. Due to the perishable natures, fruits and vegetables can not be stored in natural conditions for long period of time. Conventional methods are also applicable for preserving fruits and vegetables but because of few limitations like high cost, unsatisfactory results, or poor shelf life improvement are not preferred. Nanotechnology has not reported any harmful effects till now hence it can be effectively utilized in the food industry. Also, the shelf life of fruits and vegetables can be effectively improved by utilization of nanotechnology. Providing safe and sufficient food to the customers, reducing the post harvest wastages and the losses during production has became the native aim of food manufacturers. To reduce the losses and wastages is the major challenge before food industries which has a best solution named nanotechnology or nano-packaging. Nanomaterials are the core of the nanotechnology . Nanomaterials plays an important role in food preservation due to its unique characteristic of developing enamerous ability to increase the physical properties of the food as well as packaging materials. Nanopacking or nano-packaging is useful for lowering the relative humidity, oxygen transmission rate and water vapor transmission rate. Hence, it consequently improves the shelf life of the product. This review gives the idea about overall scope and demand of nanotechnology in the packaging sector to improve shelf lives of the products and liase for safety and quality of the food products.

Recently, carbon allotropes have received tremendous research interest and paved a new avenue for optical fiber sensing technology. Carbon allotropes exhibit unique sensing properties such as large surface to volume ratios, biocompatibility, and they can serve as molecule enrichers. Meanwhile, optical fibers possess a high degree of surface modification versatility that enables the incorporation of carbon allotropes as the functional coating for a wide range of detection tasks. Moreover, the combination of carbon allotropes and optical fibers also yields high sensitivity and specificity to monitor target molecules in the vicinity of the nanocoating surface. In this review, the development of carbon allotropes-based optical fiber sensors is studied. The first section provides an overview of four different types of carbon allotropes, including carbon nanotubes, carbon dots, graphene, and nanodiamonds. The second section discusses the synthesis approaches used to prepare these carbon allotropes, followed by some deposition techniques to functionalize the surface of the optical fiber, and the associated sensing mechanisms. Numerous applications that have benefitted from carbon allotrope-based optical fiber sensors such as temperature, strain, volatile organic compounds and biosensing applications are reviewed and summarized. Finally, a concluding section highlighting the technological deficiencies, challenges, and suggestions to overcome them is presented. Published version

Milka Janjic,1,2 Foteini Pappa,1 Varvara Karagkiozaki,1 Christakis Gitas,2 Kiriakos Ktenidis,2 Stergios Logothetidis1 1Department of Physics, Laboratory for Thin Films – Nanosystems and Nanometrology, University of Thessaloniki, 2School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece Abstract: This study describes the development of drug-loaded nanofibrous scaffolds as a nanocoating for endovascular stents for the local and sustained delivery of rosuvastatin (Ros) and heparin (Hep) to injured artery walls after endovascular procedures via the electrospinning process.Purpose: The proposed hybrid covered stents can promote re-endothelialization; improve endothelial function; reduce inflammatory reaction; inhibit neointimal hyperplasia of the injured artery wall, due to well-known pleiotropic actions of Ros; and prevent adverse events such as in-stent restenosis (ISR) and stent thrombosis (ST), through the antithrombotic action of Hep.Methods: Biodegradable nanofibers were prepared by dissolving cellulose acetate (AC) and Ros in N,N-dimethylacetamide (DMAc) and acetone-based solvents. The polymeric solution was electrospun (e-spun) into drug-loaded AC nanofibers onto three different commercially available stents (Co–Cr stent, Ni–Ti stent, and stainless steel stent), resulting in nonwoven matrices of submicron-sized fibers. Accordingly, Hep solution was further used for fibrous coating onto the engineered Ros-loaded stent. The functional encapsulation of Ros and Hep drugs into polymeric scaffolds further underwent physicochemical analysis. Morphological characterization took place via scanning electron microscopy (SEM) and atomic force microscopy (AFM) analyses, while scaffolds’ wettability properties were obtained by contact angle (CA) measurements.Results: The morphology of the drug-loaded AC nanofibers was smooth, with an average diameter of 200–800nm, and after CA measurement, we concluded to the superhydrophobic nature of the engineered scaffolds. In vitro release rates of the pharmaceutical drugs were determined using a high-performance liquid chromatography assay, which showed that after the initial burst, drug release was controlled slowly by the degradation of the polymeric materials.Conclusion: These results imply that AC nanofibers encapsulated with Ros and Hep drugs have great potential in the development of endovascular grafts with anti-thrombogenic properties that can accelerate the re-endothelialization, reduce the neointimal hyperplasia and inflammatory reaction, and improve the endothelial function. Keywords: cardiovascular disease, stent, drug delivery, scaffolds, nanocoating

Marketa Bacakova,1,2 Julia Pajorova,1,2 Denisa Stranska,3 Daniel Hadraba,1,4 Frantisek Lopot,4 Tomas Riedel,5 Eduard Brynda,5 Margit Zaloudkova,6 Lucie Bacakova1 1Department of Biomaterials and Tissue Engineering, Institute of Physiology, Czech Academy of Sciences, 2Second Faculty of Medicine,Charles University, Prague, 3InStar Technologies, Liberec, 4Department of Anatomy and Biomechanics, Faculty of Physical Education and Sport, Charles University, 5Department of Chemistry and Physics of Surfaces and Biointerfaces, Institute of Macromolecular Chemistry, 6Department of Composites and Carbon Materials, Institute of Rock Structure and Mechanics, Czech Academy of Sciences, Prague, Czech Republic Abstract: Protein-coated resorbable synthetic polymeric nanofibrous membranes are promising for the fabrication of advanced skin substitutes. We fabricated electrospun polylactic acid and poly(lactide-co-glycolic acid) nanofibrous membranes and coated them with fibrin or collagen I. Fibronectin was attached to a fibrin or collagen nanocoating, in order further to enhance the cell adhesion and spreading. Fibrin regularly formed a coating around individual nanofibers in the membranes, and also formed a thin noncontinuous nanofibrous mesh on top of the membranes. Collagen also coated most of the fibers of the membrane and randomly created a soft gel on the membrane surface. Fibronectin predominantly adsorbed onto a thin fibrin mesh or a collagen gel, and formed a thin nanofibrous structure. Fibrin nanocoating greatly improved the attachment, spreading, and proliferation of human dermal fibroblasts, whereas collagen nanocoating had a positive influence on the behavior of human HaCaT keratinocytes. In addition, fibrin stimulated the fibroblasts to synthesize fibronectin and to deposit it as an extracellular matrix. Fibrin coating also showed a tendency to improve the ultimate tensile strength of the nanofibrous membranes. Fibronectin attached to fibrin or to a collagen coating further enhanced the adhesion, spreading, and proliferation of both cell types. Keywords: skin-tissue engineering, nanocoating, nanofibers, skin cells, fibrin, collagen

Nanocoating combine the protective properties of conventional coating system with effects on nanoscale such as high hardness, UV scattering, uniform dispersing, etc. Their facile and low-cost synthesis, together with superior protective properties and multi-functionalities, makes nanocoating attractive candidates for next-generation coating system. In this review, a brief introduction regarding to mainstream nanocoating and its related challenges including the zinc oxide-, titanium dioxide-, silica dioxide-, graphene-, carbon nanotube-based nanocoating system is presented. Finally, a perspective of the nanocoating is demonstrated.

Achieving surface design and control of biomaterial scaffolds with nanometer- or micrometer-scaled functional films is critical to mimic the unique features of native extracellular matrices, which has significant technological implications for tissue engineering including cell-seeded scaffolds, microbioreactors, cell assembly, tissue regeneration, etc. Compared with other techniques available for surface design, layer-by-layer (LbL) self-assembly technology has attracted extensive attention because of its integrated features of simplicity, versatility, and nanoscale control. Here we present a brief overview of current state-of-the-art research related to the LbL self-assembly technique and its assembled biomaterials as scaffolds for tissue engineering. An overview of the LbL self-assembly technique, with a focus on issues associated with distinct routes and driving forces of self-assembly, is described briefly. Then, we highlight the controllable fabrication, properties, and applications of LbL self-assembly biomaterials in the forms of multilayer nanofilms, scaffold nanocoatings, and three-dimensional scaffolds to systematically demonstrate advances in LbL self-assembly in the field of tissue engineering. LbL self-assembly not only provides advances for molecular deposition but also opens avenues for the design and development of innovative biomaterials for tissue engineering.

Yao-Yao Yang,1,* Zhe-Peng Liu,2,* Deng-Guang Yu,1 Ke Wang,1 Ping Liu,1 Xiaohong Chen1 1School of Materials Science and Engineering, University of Shanghai for Science and Technology, Shanghai, China; 2School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China *These authors contributed equally to this work Background: Colon-specific pulsatile drug release, as a combined drug controlled-release model, is a useful drug delivery manner for a series of diseases. New nanomedicines and related preparation methods are highly desired. Methods: With diclofenac sodium (DS) as a model drug, a new type of structural nanocomposite (SC), in which composite polyvinylpyrrolidone (PVP)–DS core was coated by shellac, was fabricated via modified coaxial electrospinning. For comparison, traditional PVP–DS monolithic hydrophilic nanocomposites (HCs) were generated using a traditional blending process. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), water contact angle (WCA), and in vitro dissolution and ex vivo permeation tests were conducted to characterize the composites. Results: SEM images demonstrated that both composites were linear nanofibers with smooth surface morphology and cross sections. TEM disclosed that the SCs had a thin shellac sheath layer of approximately 12 nm. XRD and ATR-FTIR results demonstrated that the crystalline DS was converted into amorphous composites with PVP because of favorable secondary interactions. WCA and in vitro dissolution tests demonstrated that the sheath shellac layers in SC could resist acid conditions and provide typical colon-specific pulsatile release, rather than a pulsatile release of HC under acid conditions. Ex vivo permeation results demonstrated that the SCs were able to furnish a tenfold drug permeation rate than the DS particles on the colon membrane. Conclusion: A new SC with a shellac coating on hydrophilic amorphous nanocomposites could furnish a colon-specific pulsatile drug release profile. The modified coaxial process can be exploited as a useful tool to create nanocoatings. Keywords: modified coaxial electrospinning, nanocoating, colon-targeted, pulsatile release, structural composites

Brick constitutes a significant part of the construction materials used in historic buildings around the world. This material was used in Architectural Heritage for structural scope, and even for building envelopes. Thus, components made of clay brick were subjected to weathering for a long time, and this causes their deterioration. One of the most important causes for deterioration is biodeterioration caused by algae and cyanobacteria. It compromises the aesthetical properties, and, at a later stage, the integrity of the elements. In fact, traditional products used for the remediation/prevention of biofouling do not ensure long-term protection, and they need re-application over time. The use of nanotechnology, especially the use of photocatalytic products for the prevention of organic contamination of building façades is increasing. In this study, TiO2-based photocatalytic nano-coatings were applied to ancient brick, and its efficiency towards biofouling was studied. A composed suspension of algae and cyanobacteria was sprinkled on the bricks’ surface for a duration of twelve weeks. Digital Image Analysis and colorimetric measurements were carried out to evaluate algal growth on specimens’ surfaces. Results show that photocatalytic nano-coating was able to inhibit biofouling on bricks’ surfaces. In addition, substrata (their porosity and roughness) clearly influences the adhesion of algal cells.

Electrospinning, as a promising platform in multidisciplinary engineering over the past two decades, has overcome major challenges and has achieved remarkable breakthroughs in a wide variety of fields such as energy, environmental, and pharmaceutics. However, as a facile and cost-effective approach, its capability of creating nanofibers is still strongly limited by the numbers of treatable fluids. Most recently, more and more efforts have been spent on the treatments of liquids without electrospinnability using multifluid working processes. These unspinnable liquids, although have no electrospinnability themselves, can be converted into nanofibers when they are electrospun with an electrospinnable fluid. Among all sorts of multifluid electrospinning methods, coaxial electrospinning is the most fundamental one. In this review, the principle of modified coaxial electrospinning, in which unspinnable liquids are explored as the sheath working fluids, is introduced. Meanwhile, several typical examples are summarized, in which electrospun nanofibers aimed for the environment remediation were prepared using the modified coaxial electrospinning. Based on the exploration of unspinnable liquids, the present review opens a way for generating complex functional nanostructures from other kinds of multifluid electrospinning methods.

Hydrophobic layers are generated and chemisorbed onto standard coating materials for photovoltaic (PV) devices in order to improve their barrier properties against the atmospheric degradation agents and achieve a higher lifetime for the coated devices. The hydrophobic layers are deposited on PET–SiOx substrates using two different molecules (alkylsilanes and fluoroalkylsilanes) as precursors. High liquid barrier properties are achieved for the fluoroalkylsilane coated PET–SiOx, best results being average water contact angle > 130° and average oil contact angle > 90°. A chemical mechanism hypothesis is provided in order to explain the different reactive behavior observed for the PET–SiOx samples with alkylsilanes and fluoroalkylsilanes, respectively. Moreover, the oxygen barrier properties are significantly improved by the fluoroalkylsilane layer deposited in ethanol, that leads to a 70% reduction of the Oxygen Transmission Rate (OTR) compared to that of the uncoated PET–SiOx substrate.

The present study shows the results of direct ceramization of textile substrates with commercial derived TiO2 nanosols. A deep investigation on relationship between TiO2 based nanosols and nanocoatings properties and their performances in term of hydrophilicity and photocatalytic efficiency was performed. Five nanosols, differing for starting pH and relative agglomerates size were analyzed. The hydrophilic behavior and the catalytic performance of TiO2 coatings supported on different substrates (fabric, glass and ceramic) were assessed and related to physicochemical characterization results. The described correlations between TiO2 nanoscale properties (nanostructure or surface chemistry), macroscale properties (hydrophilicity), as well as functional properties (photocatalytic activity), represents a first attempt to provide sound criteria for the control of material performance by design experiments. The pH dependent aggregation state, is correlated to an increase of surface acidity as the shift of i.e.p. towards acid pH reveals. Such increase of acidity justifies an increase of hydrophilicity, consequent to stronger interaction with water molecules, that occurs when a higher amount of Ti−O− sites are available. As well, the photocatalytic performances and the hydrophilic behavior, resulted in a good agreement: the higher the hydrophilicity, the better the self-cleaning activity, so providing useful indications for the scale-up exploitation of such application.

Glaucoma is one of the leading causes of blindness. When medical therapy is not effective in reducing the intraocular pressure, a surgical approach is needed. Trabeculecomy is the gold standard procedure, but new minimally invasive techniques are available. The ExPress glaucoma shunt is recognized as one of the most promising options and its characterization and possible improvements are the aim of the present study. The device was physically and chemically characterized. SEM images were obtained and the ExPress implant was analyzed in all aspects. Surprisingly, a high degree of roughness was observed on the surface of the internal lumen. This may cause cell adhesion and fibrin deposition, eventually leading to obstruction of the device and failure of the surgery. Cell adhesion was studied with the use of cell cultures of fibroblasts. A limited degree of cell adhesion was demonstrated on the inner lumen of the device. On an explanted Ex-Press device from a human eye, a discrete amount of biological extracellular matrix was observed. The use of energy-dispersive X-ray spectroscopy was used to demonstrate the presence of carbon on the device. Evidence of possible cell growth and extracellular matrix deposition on the device was therefore demonstrated. Moreover, a massive bacterial contamination occurred, suggesting possible infection transmission in vivo. The second part of the research was dedicated to define a computational model in order to study the effect of the scleral flap and the suture position on the filtration rate. A 2 D model and a 3D model were studied to simulate the outflow of aqueous from the eye. Interestingly, we demonstrated the role of the suture placing in determining the pathways of outflow. The 3D model was useful to better understand the deformation of the scleral flap and it suggested a role of the head position on the outflow pattern. Most of the outflow was estimated to occur at the sides of the scleral flap, within 2 mm from the corneal side. Subsequently, a nanocoating was planned in order to reduce cell and bacterial adhesion on the device. The procedure allowed the formation of a layer of fluorinated silanes and polymer grafting chains, possibly with biologically active moieties. After the silane treatment, different polymers were tested using the “grafting from” technique. Grafting from technique is based on the growth of polymers directly from the surface previously functionalized with the proper species. Monomers employed were styrene, methylmethacrylate and N,N-dimethylacrylamide. The experiments were carried out on stainless steel (SS) 316L 1x1 cm plates, in order to test the same material of the device, but with easier handling. Contact angle measures and atomic force microscopy analysis were performed to characterize the samples. Samples were then tested for bacterial adhesion. In order to verify the anti adhesion properties, samples were compared with pristine SS plates. Samples and pristine plates were immersed in a solution of Staphylococcus Aureus, properly incubated, washed and treated in order to permit a bacteria count. The bacterial adhesion analysis showed that the Polystyrene treated plates demonstrated the lowest bacterial adhesion and vitality, while the effect of Polymethylmethacrylate and PolyN,N-dimethylacrylamide was less evident

A critical challenge to the development of large-scale artificial tissue grafts for defect reconstruction is vascularization of the tissue construct. As an emerging tissue/organ manufacturing technique, 3D bioprinting offers great precision in controlling the internal architecture of a scaffold with preferable mechanical strength and printing complicated microstructures comparable to native tissue. However, current bioprinting techniques still exhibit difficulty in achieving biomimetic nano resolution and cooperating with bioactive spatiotemporal signals. In this study, a comprehensive design of engineered vascularized bone construct is presented for the first time by integrating biomimetic 3D bioprinted fluid perfused microstructure with biologically inspired smart release nanocoating, which is regarded as an aspiring concept combining engineering, biological, and material science. In this biologically inspired design, angiogenesis and osteogenesis are successively induced through a matrix metalloprotease 2 regulative mechanism by delivering dual growth factors with sequential release in spatiotemporal coordination. Availability of this system is evaluated in dynamic culture condition, which is similar to fluid surrounding in vivo, as an alternative animal model study. Results, particularly from co-cultured dynamically samples demonstrate excellent bioactivity and vascularized bone forming potential of nanocoating modified 3D bioprinted scaffolds for human bone marrow mesenchymal stem cells and human umbilical vein endothelial cells.

Microcrystalline cellulose is a commonly used direct compression tablet diluent and binder. It is derived from purified α-cellulose in an environmentally unfriendly process that involves mineral acid catalysed hydrolysis. In this study Kraft softwood fibers was nanocoated using a layer-by-layer self-assembling process. Powder flow and compactibility results showed that the application of nano-thin polymer layers on the fibers turned non-flowing, non-compacting cellulose into powders that can be used in the direct compression of tablets. The powder flow properties and tableting indices of compacts compressed from these nanocoated microfibers were similar or better than that of directly compactible microcrystalline cellulose powders. Cellulose microfibers coated with four PSS/PVP bilayers had the best compaction properties while still producing tablets that were able to absorb water and disintegrate and did not retard the dissolution of a model drug acetaminophen. The advantages of nanocoating rather than traditional pharmaceutical coating are that it add less than 1% to the weight of the fibers and allows control of the molecular properties of the surface and the thickness of the coat to within a few nanometers. This process is potentially friendlier to the environment because of the type and quantity of materials used. Also, it does not involve acid-catalyzed hydrolysis and neutralization of depolymerized cellulose. http://dx.doi.org/10.1016/j.ijpharm.2010.10.056

Wei Zhu,1 George Teel,1 Christopher M O’Brien,1 Taisen Zhuang,1 Michael Keidar,1 Lijie Grace Zhang1–3 1Department of Mechanical and Aerospace Engineering, 2Department of Biomedical Engineering, 3Department of Medicine, The George Washington University, Washington, DC, USA Abstract: Surface modification of titanium for use in orthopedics has been explored for years; however, an ideal method of integrating titanium with native bone is still required to this day. Since human bone cells directly interact with nanostructured extracellular matrices, one of the most promising methods of improving titanium’s osseointegration involves inducing biomimetic nanotopography to enhance cell–implant interaction. In this regard, we explored an approach to functionalize the surface of titanium by depositing a thin film of textured titanium nanoparticles via a cathodic arc discharge plasma. The aim is to improve human bone marrow mesenchymal stem cell (MSC) attachment and differentiation and to reduce deleterious effects of more complex surface modification methods. Surface functionalization was analyzed by scanning electron microscopy, atomic force microscopy, contact angle testing, and specific protein adsorption. Scanning electron microscopy and atomic force microscopy examination demonstrate the deposition of titanium nanoparticles and the surface roughness change after coating. The specific fibronectin adsorption was enhanced on the modified titanium surface that associates with the improved hydrophilicity. MSC adhesion and proliferation were significantly promoted on the nanocoated surface. More importantly, compared to bare titanium, greater production of total protein, deposition of calcium mineral, and synthesis of alkaline phosphatase were observed from MSCs on nanocoated titanium after 21days. The method described herein presents a promising alternative method for inducing more cell favorable nanosurface for improved orthopedic applications. Keywords: titanium, mesenchymal stem cell, plasma, nanocoating, orthopedics

Thermoelectricity is a very important physical property, especially its significance in heat-electricity conversion. If thermoelectric devices can be effectively applied to the recovery of the renewable energies, such as waste heat and solar energy, the energy shortage and global warming issues may be greatly relieved. This review focusses recent developments on the thermoelectric performance of a low-dimensional material, bulk nanostructured materials, conventional bulk materials etc. Particular emphasis is given on, how the nanostructure in nanostructured composites, confinement effects in one-dimensional nanowires and doping effects in conventional bulk composites plays an important role in ZT enhancement.

Preučevali smo možnosti uporabe avtomobilskega laka na bukovi in tako imenovanega nanopremaza ter komercialnega premaza na robinijevi podlagi. Vzorce smo izpostavili umetnemu pospešenemu staranju in izmerili debeline filmov, določili permeabilnost, barvo in sijaj. Ugotovili smo, da avtomobilski lak, kljub svoji optimiranosti za uporabo na vozilih, ni primeren za zunanjo zaščito lesa, saj je preveč nepermeabilen. V procesu staranja je površina razpokala lak se je dobro odrezal le pri zaščiti podlage pred fotodegradacijo in diskoloracijo. Tudi nanopremaz se ni obnesel, saj ni zaščitil podlage pred fotodegradacijo sijaj se mu je med umetnim pospešenim staranjem občutno spremenil, prav tako je bil podvržen izpiranju s podlage. Komercialni premaz se je izkazal najbolje permeabilnost je bila zadovoljiva, kar se je kasneje pokazalo tudi pri umetnem pospešenem staranju. Spremembe barve in sijaja bi lahko ocenili kot majhne, saj razen rahle potemnitve in izgube sijaja, površina ni bistveno spremenila svojega izgleda. Menimo, da bi bilo z nadaljnjimi raziskavami smiselno proučiti in primerjati več sodobnih premazov med seboj, se posebno če bi jih dodatno modificirali. Possible applications of the automobile coating on beech wood substrate, and the so called nano-coating and the commercially obtainable wood finish on robinia substrate, were studied. The samples were exposed to artificially accelerated ageing. Coating layers thickness was measured and permeability, colour and gloss determined. It was found out that the automobile coating, in spite of its optimal properties for the use on vehicles, is not appropriate for protection of wood exposed outdoors. During the process of aging, the surface of the automobile coating cracked, because it was not permeable enough. This finish proved its applicability only for the protection of a substrate against photodegradation and discolourations. The nano-coating also did not perform well it did not protect the substrate against photodegradation, and furthermore, its gloss changed during artificial ageing it also was subjected to leaching. On the contrary, the commercially available and established finish exhibited much better properties. Its permeability was satisfying, what was proved later during the accelerated aging. Changes of colour and gloss were estimated as insignificant - beside only slight darkening and loss of gloss, the appearance of the surface did not change essentially. We believe that it would be well to investigate and compare a wider spectrum of contemporary coatings, especially when additionally modified.

Marketa Bacakova,1,2 Jana Musilkova,1 Tomas Riedel,3 Denisa Stranska,4 Eduard Brynda,3 Margit Zaloudkova,5 Lucie Bacakova1 1Department of Biomaterials and Tissue Engineering, Institute of Physiology, Czech Academy of Sciences, 2Second Faculty of Medicine, Charles University in Prague, 3Institute of Macromolecular Chemistry, Czech Academy of Sciences, Prague, 4InStar Technologies, Liberec, 5Institute of Rock Structure and Mechanics, Czech Academy of Sciences, Prague, Czech Republic Abstract: Fibrin plays an important role during wound healing and skin regeneration. It is often applied in clinical practice for treatment of skin injuries or as a component of skin substitutes. We prepared electrospun nanofibrous membranes made from poly(L-lactide) modified with a thin fibrin nanocoating. Fibrin surrounded the individual fibers in the membrane and also formed a thin fibrous mesh on several places on the membrane surface. The cell-free fibrin nanocoating remained stable in the cell culture medium for 14days and did not change its morphology. Onmembranes populated with human dermal fibroblasts, the rate of fibrin degradation correlated with the degree of cell proliferation. The cell spreading, mitochondrial activity, and cell population density were significantly higher on membranes coated with fibrin than on nonmodified membranes, and this cell performance was further improved by the addition of ascorbic acid in the cell culture medium. Similarly, fibrin stimulated the expression and synthesis of collagen I in human dermal fibroblasts, and this effect was further enhanced by ascorbic acid. The expression of beta1-integrins was also improved by fibrin, and on pure polylactide membranes, it was slightly enhanced by ascorbic acid. In addition, ascorbic acid promoted deposition of collagen I in the form of a fibrous extracellular matrix. Thus, the combination of nanofibrous membranes with a fibrin nanocoating and ascorbic acid seems to be particularly advantageous for skin tissue engineering. Keywords: electrospun nanofibers, nanocoating, skin tissue engineering, fibroblasts, fibrin, ascorbic acid, nanotechnology, nanomedicine, collagen I synthesis, beta1-integrins

In the present work, thermal evaporation and sol–gel coating techniques were applied to fabricate nanostructured thin ZnO films. The phase structure and surface morphology of the obtained films were investigated by X-ray diffractometer (XRD) and scanning electron microscope (SEM), respectively. The topography and 2D profile of the thin ZnO films prepared by both techniques were studied by optical profiler. The results revealed that the thermally evaporated thin film has a comparatively smoother surface of hexagonal wurtzite structure with grain size 12 nm and 51 m2/g. On the other hand, sol–gel films exhibited rough surface with a strong preferred orientation of 25 nm grain size and 27 m2/g surface area. Following deposition process, the obtained films were applied for the photodegradation of 2,4,6-trichlorophenol (TCP) in water in presence of UV irradiation. The concentrations of TCP and its intermediates produced in the solution during the photodegradation were determined by high performance liquid chromatography (HPLC) at defined irradiation times. Complete decay of TCP and its intermediates was observed after 60 min when the thermal evaporated photocatalyst was applied. However, by operating sol–gel catalyst, the concentration of intermediates initially increased and then remained constant with irradiation time. Although the degradation of TCP followed first-order kinetic for both catalysts, higher photocatalytic activity was exhibited by the thermally evaporated ZnO thin film in comparison with sol–gel one.

The influences of the spray-drying parameters and the type of nanoparticles (nanocapsules or nanospheres) on the characteristics of nanoparticle-coated diclofenac-loaded microparticles were investigated by using a factorial design 32. Gastrointestinal tolerance following oral administration in rats was evaluated. Formulations were selected considering the best yields, the best encapsulation efficiencies and the lowest water contents, presenting surfaces completely coated by nanostructures and a decrease in the surface areas in relation to the uncoated core. In vitro drug release demonstrated the influence of the nanoparticle-coating on the dissolution profiles of diclofenac. Nanocapsule-coated microparticles presented a protective effect on the gastrointestinal mucosa.

A chemical method to coat submicron silica particles with nanocrystalline zinc sulfide is described. The ZnS nanocoating was obtained by the thermalysis of zinc diethyldithiocarbamate in the presence of morphologically well defined silica particles. The powders obtained were isolated and were characterized by UV/visible optical reflectance, scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The results showed that the silica surfaces became homogeneously coated with ZnS as the reaction time was increased. This coating consists in clusters of small ZnS particles whose dimensions are within the nanometric range.