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Preparation of microfiber structures based on PHB copolymer
Kecíková, Alžbeta ; Brtníková, Jana (referee) ; Přikryl, Radek (advisor)
Master’s thesis deals with the preparation of microfibrous structures based on poly(3-hydroxybutyrate) (P3HB) and its copolymer with poly(4-hydroxybutyrate) using centrifugal spinning technology. The microfibers were modified by the addition of oligomer P3HB and a plasticizer. The centrifugal spinning process was optimized for each material by solution viscosity, polymer molecular weight, speed of spineret, and presence of solvent. One of the part of optimalization was the addition of formic acid and acetic acid to the dissolution system. Microfibrous structures have been investigated in terms of morphology, mechanical properties, wetting and biocompatibility. P3HB fibers were also surface treated with lipase solutions to reduce their hydrophobicity. The prepared bulky fiber cocoons have a suitable 3D microstructure for monitoring and testing biological properties in vitro. Thus, a potential application of microfiber structures is as 3D cell culture carriers in an scaffolds in vitro system.
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Microfibers based on polyhydroxybutyrate for medical applications
Gregušková, Zuzana ; Obruča, Stanislav (referee) ; Přikryl, Radek (advisor)
Diplomová práca je zameraná na mikrovlákna na báze biopolyméru poly(3-hydroxybutyrátu) a ich využitie v medicínskych aplikáciách. Teoretická časť práce sa zaoberá štúdiom procesu tvorby vláken pomocou technológie odstredivého zvlákňovania, jeho kinetikou a faktormi ovplyvňujúcimi vznik a vlastnosti vláken. Teoretická časť sa následne orientuje na krátky prehľad biopolymérov používaných v tejto technológii, charakteristiku materiálu poly(3-hydroxybutyrátu) a taktiež prezentuje návrh potenciálnej cieľovej aplikácie daných mikrovláken. Praktická časť sa koncentruje sa prípravu mikrovláken zo spomínaného poly(3-hydroxybutyrátu). Sledované a optimalizované sú viaceré parametre vedúce k lepšej zvlákniteľnosti materiálu. Praktická časť je rozšírená o modifikáciu polymérneho roztoku prídavkom iných biopolymérov a zmäkčovadiel a prípravu mikrovláken z takto modifikovanej polymérnej zmesi. Pozornosť je venovaná taktiež optimalizácii procesných parametrov. Pripravené mikrovlákna sú následne analyzované a charakterizované viacerými metódami a vzájomne porovnávané s cieľom vyvinúť alternatívu k súčasne používaným substrátom pre rast buniek v 3D.
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Preparation of microfiber structures based on PHB copolymer
Kecíková, Alžbeta ; Brtníková, Jana (referee) ; Přikryl, Radek (advisor)
Master’s thesis deals with the preparation of microfibrous structures based on poly(3-hydroxybutyrate) (P3HB) and its copolymer with poly(4-hydroxybutyrate) using centrifugal spinning technology. The microfibers were modified by the addition of oligomer P3HB and a plasticizer. The centrifugal spinning process was optimized for each material by solution viscosity, polymer molecular weight, speed of spineret, and presence of solvent. One of the part of optimalization was the addition of formic acid and acetic acid to the dissolution system. Microfibrous structures have been investigated in terms of morphology, mechanical properties, wetting and biocompatibility. P3HB fibers were also surface treated with lipase solutions to reduce their hydrophobicity. The prepared bulky fiber cocoons have a suitable 3D microstructure for monitoring and testing biological properties in vitro. Thus, a potential application of microfiber structures is as 3D cell culture carriers in an scaffolds in vitro system.
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Microfibers based on polyhydroxybutyrate for medical applications
Gregušková, Zuzana ; Obruča, Stanislav (referee) ; Přikryl, Radek (advisor)
Diplomová práca je zameraná na mikrovlákna na báze biopolyméru poly(3-hydroxybutyrátu) a ich využitie v medicínskych aplikáciách. Teoretická časť práce sa zaoberá štúdiom procesu tvorby vláken pomocou technológie odstredivého zvlákňovania, jeho kinetikou a faktormi ovplyvňujúcimi vznik a vlastnosti vláken. Teoretická časť sa následne orientuje na krátky prehľad biopolymérov používaných v tejto technológii, charakteristiku materiálu poly(3-hydroxybutyrátu) a taktiež prezentuje návrh potenciálnej cieľovej aplikácie daných mikrovláken. Praktická časť sa koncentruje sa prípravu mikrovláken zo spomínaného poly(3-hydroxybutyrátu). Sledované a optimalizované sú viaceré parametre vedúce k lepšej zvlákniteľnosti materiálu. Praktická časť je rozšírená o modifikáciu polymérneho roztoku prídavkom iných biopolymérov a zmäkčovadiel a prípravu mikrovláken z takto modifikovanej polymérnej zmesi. Pozornosť je venovaná taktiež optimalizácii procesných parametrov. Pripravené mikrovlákna sú následne analyzované a charakterizované viacerými metódami a vzájomne porovnávané s cieľom vyvinúť alternatívu k súčasne používaným substrátom pre rast buniek v 3D.
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Intelligent nanofibres functionalized with growth factors and blood derivatives for dermatology applications
Vocetková, Karolína ; Amler, Evžen (advisor) ; Rosina, Jozef (referee) ; Arenberger, Petr (referee)
Platelet derivatives are an attractive source of natural growth factors and they are widely used in various tissue engineering and regenerative medicine applications. The aim of this study was to optimize cell culture conditions using platelet lysate and to develop platelet-functionalized fibrous scaffolds as a controlled drug delivery system for native growth factors. Fibrous scaffolds were prepared by electrostatic and centrifugal spinning of PCL and they were functionalized by the platelets by surface adhesion or their encapsulation using emulsion spinning techniques. The cell culture study determined the 7% platelet lysate to be the optimum concentration as a medium supplement in keratinocyte and fibroblast culture. Additionally, following surface adhesion of the platelets to PCL electrospun nanofibres, the platelets were activated due to their contact with the nanofibre nanotopography, resulting in formation of fibrin network. Fibrin served as a reservoir of the growth factors, prolonging the half-time of EGF release to 1.7 days. Such platelet-functionalized samples fostered proliferation of keratinocytes, fibroblasts and melanocytes. Furthermore, adhesion of platelets to centrifugally spun nanofibrous scaffolds resulted in almost two-fold increase in the amount of immobilized platelet-derived...
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Coaxial nanofibers with incorporated suplements for regulated chondrogenic differentiation
Korbelová, Gabriela ; Rampichová, Michala (advisor) ; Vištejnová, Lucie (referee)
In the field of regenerative medicine, regeneration of cartilage defects (caused either by injury or age-related degeneration) has become a widely discussed topic. Nanofibrous scaffolds provide a suitable environment for cell adhesion, proliferation, differentiation, and also for the local involvement of bioactive substances. Nanofibrous scaffolds mimic the extracellular matrix (ECM) of hyaline cartilage. These scaffolds are seeded with autologous chondrocytes. After having been isolated from the patient, the cells must be cultivated in vitro in order to obtain a sufficient amount of chondrocytes. Scaffolds with cultivated chondrocytes are later implanted back into the pacient. Chondrocytes, however, when grown on a 2D tissue culture plastic rapidly de-differentiate and thus lose the ability to synthesize ECM molecules. The aim of the work was modulation of chondrogenic differentiation medium through finding the ideal concentration of chondrogenic supplements, composed of L-ascorbate-2-phosphate (A2P) and dexamethasone (DEX), in the culture of primary chondrocytes seeded on a nanofibrous polycaprolactone (PCL) scaffold. The effect of different concentrations of the chondrogenic supplements on chondrocyte adhesion to the scaffold and their proliferation and differentiation was studied. The influence...
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Coaxial nanofibers with incorporated supplements for regulated chondrogenic differentiation
Korbelová, Gabriela ; Rampichová, Michala (advisor) ; Vištejnová, Lucie (referee)
In the field of regenerative medicine, regeneration of cartilage defects (caused either by injury or age-related degeneration, such as osteoporosis) has become a widely discussed topic. Nanofibrous scaffolds provide a suitable environment for cell adhesion, proliferation, differentiation, and also local involvement of bioactive substances. Nanofibrous scaffolds mimic the extracellular matrix (ECM) of hyaline cartilage and thus have the potential to treat cartilage defects. The aim of the work was modulation of chondrogenic differentiation medium through finding the ideal concentration of chondrogenic supplements, composed of ascorbate-2- phosphate and dexamethasone, in the culture of primary chondrocytes of pig origin seeded on a nanofibrous polycaprolactone (PCL) scaffold. The effect of different concentrations of the chondrogenic supplements on chondrocyte adhesion to the scaffold and their proliferation and differentiation was studied. Firstly, the influence of each of the supplements alone in the medium was studied, followed by study of effects of their combinations. Then, the supplements were incorporated into the nanofibers and their effect upon their release from the nanofibers was investiaged. The supplements were studied in 21-day experiments. The chondrogenic re- differentiation was best...
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