Nanocellulosic Materials in Tissue Engineering Applications

This chapter deals with an overview of design and fabrication of three-dimensional (3D) scaffolds for tissue engineering (TE) applications using the electrospinning technique. A general introduction to cellulose, a short overview of sources and methodology for the production of cellulose nanocrystals (CNCs), and principles of tissue engineering and the electrospinning technique will be given. Applications for CNCs are manifold and range from super water absorbent, drug delivery, packaging, personal care to pharmaceuticals. However, in this chapter the application in tissue engineering will be discussed in detail

Patterned Surface Activation of Cyclo-Olefin Polymers for Biochip Applications

Two different surface activation methods (UV/ozone and oxygen plasma treatment) were applied for patterned surface activation of cyclo-olefin polymer (COP) surfaces combined with different masking techniques (metal shadow mask and protective tape). Surface properties were characterized by various methods such as contact angle measurement, ATR-IR, XPS and Surface enhanced ellipsometric contrast (SEEC) microscopy. UV/ozone and oxygen plasma allowed for patterned surface modification of COP leading to the formation of carboxylic and hydroxyl groups on the activated part of the surface. Stability against organic solvents was determined by rinsing the activated substrates with 2-propanol. For UV/ozone treatment it was found that a thin film of degradation products remains on the COP surface and is at least partly removed in the following washing or rinsing steps

Morphology and swelling of thin films of dialcohol xylan

Polysaccharides are excellent network formers and are often processed into films from water solutions. Despite being hydrophilic polysaccharides, the typical xylans liberated from wood are sparsely soluble in water. We have previously suggested that an additional piece to the solubilization puzzle is modification of the xylan backbone via oxidative cleavage of the saccharide ring. Here, we demonstrate the influence of the degree of modification, i.e., degree of oxidation (DO) on xylan solubilization and consequent film formation and stability. Oxidized and reduced wood xylans (i.e., dialcohol xylans) with the highest DO (77 %) within the series exhibited the smallest hydrodynamic diameter (dh) of 60 nm in dimethylsulfoxide (DMSO). We transferred the modified xylans into films credit to their established solubility and then quantified the film water interactions. Dialcohol xylans with intermediate DOs (42 and 63 %) did not form continuous films. The films swelled slightly when subjected to humidity. However, the film with the highest DO demonstrated a significant moisture uptake that depended on the film mass and was not observed with the other modified grades or with unmodified xylan

Photoregeneration of Trimethylsilyl Cellulose as a Tool for Microstructuring Ultrathin Cellulose Supports

Microstructured thin films based on cellulose, the most abundant biopolymer on Earth, have been obtained by UV-irradiation of acid-labile trimethylsilyl cellulose thin films in the presence of N-hydroxynaphtalimide triflate as photoacid generator. We demonstrate that this photoregeneration process can be exploited for the manufacture of cellulose patterns having feature sizes down to 1 μm, with potential applications in life sciences

Photoregeneration of trimethylsilyl cellulose as a tool for microstructuring ultrathin cellulose supports

Microstructured thin films based on cellulose, the most abundant biopolymer on Earth, have been obtained by UV-irradiation of acid-labile trimethylsilyl cellulose thin films in the presence of N-hydroxynaphtalimide triflate as photoacid generator. We demonstrate that this photoregeneration process can be exploited for the manufacture of cellulose patterns having feature sizes down to 1 μm, with potential applications in life sciences

Oblikovanje, karakterizacija in uporaba tankih filmov, nanovlaken in 3D tiskanih struktur na osnovi celuloze

The introduction of the Laboratory Manual gives the theoretical bases on cellulose and its derivatives, which are used as starting polymers for the preparation of multifunctional polymers with three different advanced techniques - spin coating, electrospinning and 3D printing. In the following, each technique is presented in a separate Lab Exercise. Each exercise covers the theoretical basics on techniques for polymer processing and methods for their characterisation, with an emphasis on the application of prepared materials. The experimental sections contain all the necessary information needed to implement the exercises, while the added results provide students with the help to implement correct and successful exercises and interpret the results.Uvod v laboratorijski priročnik daje teoretične podlage o celulozi in njenih derivatih, ki se uporabljajo kot začetni polimeri za pripravo večnamenskih polimerov s tremi različnimi naprednimi tehnikami - spin premazom, elektrospinovanjem in 3D-tiskanjem. V nadaljevanju je vsaka tehnika predstavljena v ločeni laboratorijski vaji. Vsaka vaja zajema teoretične osnove tehnik za obdelavo polimerov in metode njihove karakterizacije s poudarkom na uporabi pripravljenih materialov. Eksperimentalni razdelki vsebujejo vse potrebne informacije, potrebne za izvedbo vaj, dodani rezultati pa učencem pomagajo pri izvajanju pravilnih in uspešnih vaj ter interpretirajo rezultate