The antimicrobial activity of chitosan is assigned to its amino groups, which in diluted acids form ammonium salts. The manipulation of chitosan’s binding strategies onto cellulose surfaces i.e.: (i) reversible binding – which enables the release of a bioactive substance from a fibre’s surface and, (ii) irreversible binding resulting in the permanent bioactivity of a fibrous (textile) surface, determines the applicabilities of such surfaces. Successful permanent chitosan binding with a large number of accessible amino groups requires a certain amount of anchoring sites on the fibrous substrate. However, interactions with the anchoring groups lower the free amino groups’ amount and as such decreases the surface antimicrobial activity of the treated fibres. In order to achieve satisfactory results, it is extremely important to balance between treatment résistance, materials’ mechanical properties, and the number of free amino groups in/on the treated material.
B.06 Other
COBISS.SI-ID: 14514966The sensitive and selective detection of warfare threats is very important for military as well as for homeland security. This article gives a brief overview on the use of optical chemical sensors and probes based on nanomaterials for defence applications. The emphasis is on the detection of explosives (EXPs) and chemical warfare agents (CWAs). The detection transduction schemes that are used in optical nanosensors for EXPs and CWAs are overviewed and recently published works are described. However, there is still not a single nano-based sensor that promises a combination of speed, selectivity and sensitivity.
B.06 Other
COBISS.SI-ID: 16975638The textile industry is very diverse, heterogeneous, and characterized by high consumption of water, fuel, and chemicals. Environmental problems are mainly associated with wastewater. With regard to globalization and scarcity of water, wastewater treatment and recycling possibilities in the textile industry are of the highest importance. In this chapter, raw materials and processes used in textile industry are briefly discussed, with special attention given to characteristics of textile water supply and wastewater produced from different process steps. The general characteristics of textile wastewater and wastewater-treatment technologies are described and reuse possibilities are discussed.
B.06 Other
COBISS.SI-ID: 14770966Owing to their abundance polysaccharides (PS) have a huge potential to be applied in advanced applications such as functional wound dressings and textiles, biocompatible coatings, patterned thin films or nanoparticles. For many of these functions surface properties and the interactions at the PS/material interface are crucial. By having a detailed understanding of wetting, adsorption, adhesion, surface morphology and internal structure, PS materials and coatings with desired properties can be created. Spin-coated thin films of polysaccharides are one platform that can be used to elucidate these surface phenomena. Besides their defined composition and morphology they can be characterized with, and employed in, modern surface analytical methods such as a quartz-crystal microbalance and X-ray photoelectron spectroscopy. These films can further be lithographically structured and serve as a basis for functional layers in optical sensors for the detection of DNA and proteins. The biological efficacy of many charged polysaccharides can also be exploited in the coating of metal (nano-) particles. This is demonstrated by the antimicrobial and anticoagulant properties of PS coated nano-silver. Highly functional wound dressings that are antimicrobial, super-absorbing and analgesic are another example where basic and applied know-how on PS materials are leading to innovative products. In this presentation an overview on the current achievements in these fields of research will be given.
B.04 Guest lecture
COBISS.SI-ID: 17654038Subject of the invention is a method for fabrication of antimicrobial materials from natural and synthetic cellulose materials via in situ synthesis of silver nano-particles on the surface and in the interior of fibrous substrates. First phase in the process is treatment of the fibrous substrate in an alkaline solution, which has several effects in the procedure. Alkaline treatment causes swelling of the cellulose substrate, resulting in particle formation not only on the surface but in the interior of material, as well. Alkali solution also act as a source of additional reducing hydroxyl groups in the fibres interior, needed for the synthsis of silver nano-particles. Second phase of the procedure is impregnation of swollen cellulose substrate in the silver precursor solution. In the final, third phase of the production procedure, neutralization, rinsing and drying of treated material are carried out. Ag-coated cellulose fibrous material, prepared with the described procedure, has excellent antimicrobial properties even after several washing cycles. Treatment also results in an increased wetting ability of Ag-coated cellulose substrates. Synthesized particles are uniformly and discreetly placed on the surface of fibres. Due to the procedure being non-complicated, inexpensive and environmentally-acceptable, it is suitable for mass industrial production and straight-forward integration in already existing set-ups for processing of cellulose materials.
F.06 Development of a new product
COBISS.SI-ID: 16655382