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Opis: This study presents an innovative wound dressing system that offers a highly effective therapeutic solution for treating painful wounds. By incorporating the widely used non-steroidal anti-inflammatory drug diclofenac, we have created an active wound dressing that can provide targeted pain relief with ease. The drug was embedded within a biocompatible matrix composed of polyhydroxyethyl methacrylate and polyhydroxypropyl methacrylate. The multilayer structure of the dressing, which allows for sustained drug release and an exact application, was achieved through the layer-by-layer coating technique and the inclusion of superparamagnetic iron platinum nanoparticles. The multilayered dressings’ physicochemical, structural, and morphological properties were characterised using various methods. The synergistic effect of the incorporated drug molecules and superparamagnetic nanoparticles on the surface roughness and release kinetics resulted in controlled drug release. In addition, the proposed multilayer wound dressings were found to be biocompatible with human skin fibroblasts. Our findings suggest that the developed wound dressing system can contribute to tailored therapeutic strategies for local pain relief.
Ključne besede: wound dressings, pain relief, superparamagnetic nanoparticles, methacrylate
Objavljeno v DKUM: 19.04.2024; Ogledov: 485; Prenosov: 468
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Opis: In the scope of the Doctoral Dissertation, a polysaccharide based stimuli-responsive smart material with controlled drug release was developed by using electrospinning technique, which allowed to form stimuli-responsive nanofibers with rapid visual detection of pH change in the wound bed along with anti-inflammatory activity. Incorporation of halochromic dyes into electrospun nanofibers has been an intriguing area for wound healing applications. Furthermore, it is known that the pH value within the wound milieu directly and indirectly influences all biochemical reactions taking place in the process of wound healing. It has been proven that the surface pH of a wound plays an important role in wound healing as it helps control infection and increases the antimicrobial activity, oxygen release, angiogenesis, protease activity, and bacterial toxicity. Therefore, visual pH monitoring without the need of removing the wound dressing was one of the aims of the Doctoral Dissertation. Produced stimuli-responsive wound dressings were characterized according to their morphological and chemical properties using well-known techniques such as, rheometry, conductivity, Scanning Electron Microscopy (SEM),CIE Lab, Thermogravimetric Analysis (TGA), UV/VIS Spectrophotometry, and Attenuated Total Reflection Infra-Red Spectroscopy (ATR-IR). Responsiveness of the nanofibers were achieved by integration of different halochromic dyes [bromocresol green (BCG), bromothymol blue (BTB) and thymol blue (TB)] to obtain a range of pH values. To tackle the problem of leaching of the dyes, a complexing agent; poly-diallyldimethylammonium chloride (PDADMAC) was integrated and an analysis on the formation of complexation was performed by using pH-potentiometric titration and Quartz Crystal Microbalance with Dissipation (QCM-D) and Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) techniques. Additionally, release tests were performed to prove that the leaching of the halochromic dyes is reduced significantly up to 97%. Furthermore, the responsiveness of the nanofibers was investigated by exposing the nanofibers to different buffer solutions with pH values 4, 7 and 10. The color change of the nanofibers were analyzed using the CIE Lab system while a visual color shift was observed according to their characteristics. Lastly, diclofenac (DFC), an anti-inflammatory drug molecule was integrated to the system and drug release studies were performed by using Franz diffusion cells. A controlled release of the drug molecule (DFC) to the wound bed is achieved and quantitative evaluations were done. Consequently, the drug release from the smart wound dressings were identified to have two separate profiles during the release. The mathematical models that were identified to fit to the kinetics are, first-order, Korsmeyer-Peppas, and Higuchi release model, confirming the controlled drug release.
Ključne besede: stimuli-responsive, polysaccharides, wound dressings, halochromism, controlled drug release, smart materials
Objavljeno v DKUM: 06.10.2023; Ogledov: 426; Prenosov: 37
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Opis: In this work, the development of cellulose wound dressing materials with rutin (RU) and polyrutin (PR) for the healing of chronic leg ulcers is presented as a new approach of local treatment of this wound type. The flavonoid rutin is a known antioxidant substance of plant origin with wound healing promoting properties. Despite the proven beneficial properties of rutin, its potential application in wound healing is limited due to its low water solubility. This limitation can be overcome by polymerization of rutin into polyrutin. In this work an enzymatic polymerization of rutin in water without addition of organic solvents was performed to obtain a water-soluble polymer polyrutin. The chemical structure of rutin and polyrutin were investigated using UV-Vis spectroscopy, nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, size-exclusion chromatography and potentiometric titrations. Biological activity related to a desired positive influence on chronic leg ulcers was investigated through the determination of the antioxidant activity, iron-chelation ability, cell viability, determination of cell proliferation and through use of the so called “scratch assay” to measure in vitro wound healing performance. Results indicate that rutin and polyrutin have a positive influence on the healing of chronic wounds. Rutin and polyrutin water dispersions at different pH and ionic strength were further characterised by means of dynamic light scattering in order to determine the size of particles and their pH dependent ζ-potential. The knowledge gained from these measurements aided the systematic interaction studies of rutin and polyrutin dispersions with cellulose-based surfaces via model and real wound healing systems. The model cellulose surfaces were thin films prepared by dissolution of trimethylsilyl cellulose in tetrahydrofuran, spin-coating of this solution on sensors of a quartz crystal microbalance (QCM-D) and subsequent regeneration of trimethylsilyl cellulose to cellulose with acid vapors. The influence of pH, salt concentration, and rutin/polyrutin concentration on the interaction with cellulose thin films was evaluated by means of a quartz crystal microbalance with dissipation. This knowledge was transferred to the application of the coatings on real wound healing systems i.e. cellulose non-wovens. The surface morphology was further characterised on model and real wound healing systems. The antioxidant activity and release kinetics were investigated for a real wound healing system, similar to the clinically used, cellulose based wound dressing materials. The main results showed that a higher solubility of polyrutin at low ionic strength contributes to the formation of continuous layers of polyrutin on cellulose surface, while the low solubility of rutin and reduced solubility of polyrutin at higher ionic strengths contribute to deposition of particles of rutin and polyrutin on the cellulose surface. The presence of particles on the surface of non-woven cellulose fibres led to a faster initial release of rutin and polyrutin. On the contrary, a continuous layer of the well soluble polyrutin contributes to a prolonged release. Namely, adsorption of the water soluble polyrutin at pH 2 without the addition of salt results in higher masses of attached polyrutin that release slower and over longer time periods. Since wound dressing materials for chronic leg ulcers often require a lower frequency of dressing change, the latter could provide an efficient therapeutic approach to their treatment.
Ključne besede: Chronic wounds, Wound dressings, Cellulose, Polymerization of flavonoids, Rutin, Polyrutin
Objavljeno v DKUM: 11.06.2018; Ogledov: 1802; Prenosov: 246
Celotno besedilo (7,34 MB)

Opis: Biomaterials and biotechnology are increasing becoming an important area in modern medicine. The main aim in this area is the development of materials, which are biocompatible to normal tissue. Tissue-implant interactions with molecular, biological and cellular characteristics at the implant-tissue interface are important for the use and development of implants. Implantation may cause an inflammatory and immune response in tissue, foreign body reaction, systemic toxicity and imminent infection. Tissue-implant interactions determine the implant life-period. The aims of the study are to consider the biological response to implants. Biomaterials and host reactions to implants and their mechanisms are also briefly discussed.
Ključne besede: host versus graft disease, GVHD, biomaterial, wound healing, transplant, tissue, prosthetic, implants, biological response, complications
Objavljeno v DKUM: 03.08.2017; Ogledov: 1466; Prenosov: 206
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Opis: This article presents a new approach for preparing antimicrobial layer as a part of multi-composite dressing for safe and efficient wound - healing within a moist environment. Plasma polymerisation using a mixture of argon, ammonia, and hexane gases was used for preparing a thin polymer film on the poly(ethylene terephthalate) (PET) surface. The plasma deposition efficiency, regarding the amount of nitrogen, was evaluated by the Kjeldahl method, whilst the absorption of C.I. Acid Orange 7 dye onto accessible amino groups was monitored within the UV/VIS spectral region. The quantitative amount of charged surface groups was determined by potencometric titration. The results obtained using Kjeldahl method indicated the presence of a substantial amount of nitrogen within the deposited film. Furthermore, mono - azo acidic dye was absorbed onto the polymerised sample, pointing to the formation of an ionic bond between the sulphuric and amino groups. The plasma deposited PET samples resulted in inhibitions regarding all the pathogen microorganisms used, mostly those present in the infected wound.
Ključne besede: plasma polymerisation, argon, ammonia, hexane, poly(ethylene terephthalate), antimicrobial properties, wound dressing
Objavljeno v DKUM: 01.06.2012; Ogledov: 2013; Prenosov: 123
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