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Study of the interaction of hyaluronan and biocompatible amphiphilic substances
Cigánková, Hana ; Krouská, Jitka (referee) ; Mravec, Filip (advisor)
This thesis focuses on the study of the interactions between hyaluronan and selected phospholipids and their mixtures in water or buffer. First, the aggregation behavior of these lipids was measured, afterwards the influence of hyaluronan was studied. This behavior was investigated by fluorescence spectoscopy using pyrene as fluorescence probe. The Critical Agregation Concentration of the lipids before and after addition of hyaluronan was determined. The measurements revealed that the addition of hyaluronan has an observable influence on the aggregate behavior of the selected lipids and their mixtures.
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Study of surface tension of systems applied in ultrasonography.
Říkovská, Klára ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
Surface tension of sonography systems was investigated using several experiments. These experiments were comprised of measurements of surface tension using BPA-800P tensiometer. The influence of surface tension of commercial substance SonoVue®, which contains in its structure two types of phospholipids, was studied more detailed. Other phospholipids were studied to comparison with SonoVue®. All substances were dissolved in saline (0,15 M NaCl). Effect of gas type on microbubbles formation and surface tension was investigated. Some samples were studied using du Nüy ring method. It was found that gas constructing the microbubbles (air or SF6) has no impact to the surface tension value. Production of foam on the surface of solutions has an impact on the value of the surface tension. This foam degreases the surface tension. Gas pressure is significant to comparison of measured data.
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Phospholipids as the basis of biodegradable delivery systems
Burdíková, Jana ; Čeppan, Michal (referee) ; Mravec, Filip (advisor)
This thesis is focused on investigation of phospholipid-hyaluronan system. First, appropriate method for preparation of bulk solution of phospholipid/lipid and suitable fluorescence probe were chosen. Sonification was selected as a method for preparation of bulk solution and pyrene was chosen as a fluorescence probe. From the group of phospholipids lecithin was selected. Next to phospholipid, lipid with no phosphate group (DPTAP) was utilized for comparison, alternatively a mixture of lipid (DPTAP) and phospholipid (DPPC). Instead of hyaluronan another polyelectrolytes (sodium polystyrene sulfonate, sodium alginate) were used too. Measurements were performed in water environment and in phosphate buffer saline (PBS). All investigation was accomplished by fluorescence spectroscopy and dynamic light scattering.
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Theranostic systems in sonography
Říkovská, Klára ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This work deals with preparation of microbubble suspension from a mixture of phospholipids, palmitic acid and polyethylene glycol. Properties of prepared systems were studied using bubble tensiometry and dynamic light scattering method and were compared with commercial contrast agent SonoVue®. Suspensions were prepared in various conditions including different atmosphere and increased temperature in some steps of preparation and different solution. Effect of polyethylene glycol addition on surface activity of the system was studied. Surface activity of phospholipids was insignificant. Surface tension decreased with increasing concentration and molecular weight of polyethylene glycol in the system. Effect of different atmosphere and increased temperature showed no substantial trend. It emerged that dynamic light scattering is not suitable for this type of samples because of high polydispersity and phase separation of the system.
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Study of interaction between hyaluronan and phospholipid in a presence of biocompatible non-ionic surfactant
Burdíková, Jana ; Klučáková, Martina (referee) ; Mravec, Filip (advisor)
This work is based on investigation of aggregation behavior of sugar surfactants and sn-glycero-dipalmitoylphosphatidylcholin (DPPC) in aqueous environment and on study of the interactions in nonionic surfactant-DPPC and DPPC-nonionic surfactant-hyaluronan systems. Sugar surfactants were used from non-ionic surfactants. The behavior of each systems was studied by fluorescence spectroscopy. Values of critical micellar concentrations (CMC) of sugar surfactants, begining of aggregation of DPPC, DPPC aggregation effect of sugar surfactants and the effect of hyaluronan on the system non-ionic surfactant-DPPC has been investigated. Also CMC of the CPC (cetylpyrimidium chloride), which was used for fluorescence quenching in the determination of aggregate numbers of sugar surfactants, has been determined. Fluorescent probes pyrene, perylene, nile red, acridine orange and hydrophobic dye sudan red were used for measurements.
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Preparation and characterisation of mRNA/DNA transfection vectors
Horák, Tomáš ; Chmelíková, Larisa (referee) ; Skopalík, Josef (advisor)
This diploma thesis deals with genetic engineering, especially the transfection of DNA into MSCs (Mesenchymal stromal cells) and dendritic cells. Both lipoplexes and metal magnetic nanoparticles were tested to introduce the vector into cells. The research was focused on finding more efficient methods of transfection. According to analysis on MADLS and gel electrophoresis, aspects playing an important role in conjugation and subsequent transfection were found. Conjugation occurs after only 4 minutes, as evidenced by an increase in zeta potential, but to achieve full conjugation it is necessary to incubate the sample for 20 minutes. Incomplete conjugation to iron nanoparticles resulted in strong carrier-carrier interactions, which formed an unwanted conglomerates. Encapsulation into liposomes with cationic surface treatment was without complications. The success rate of GFP-labeled protein expression after transfection by these methods was calculated to be 95%, resp. 91%. This result is due to low cytotoxicity. However, commercial tested kits on dendritic cells had a success rate below 5% with high cytotoxicity.
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Preparation and characterisation of mRNA/DNA transfection vectors
Horák, Tomáš ; Chmelíková, Larisa (referee) ; Skopalík, Josef (advisor)
This diploma thesis deals with genetic engineering, especially the transfection of DNA into MSCs (Mesenchymal stromal cells) and dendritic cells. Both lipoplexes and metal magnetic nanoparticles were tested to introduce the vector into cells. The research was focused on finding more efficient methods of transfection. According to analysis on MADLS and gel electrophoresis, aspects playing an important role in conjugation and subsequent transfection were found. Conjugation occurs after only 4 minutes, as evidenced by an increase in zeta potential, but to achieve full conjugation it is necessary to incubate the sample for 20 minutes. Incomplete conjugation to iron nanoparticles resulted in strong carrier-carrier interactions, which formed an unwanted conglomerates. Encapsulation into liposomes with cationic surface treatment was without complications. The success rate of GFP-labeled protein expression after transfection by these methods was calculated to be 95%, resp. 91%. This result is due to low cytotoxicity. However, commercial tested kits on dendritic cells had a success rate below 5% with high cytotoxicity.
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Theranostic systems in sonography
Říkovská, Klára ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
This work deals with preparation of microbubble suspension from a mixture of phospholipids, palmitic acid and polyethylene glycol. Properties of prepared systems were studied using bubble tensiometry and dynamic light scattering method and were compared with commercial contrast agent SonoVue®. Suspensions were prepared in various conditions including different atmosphere and increased temperature in some steps of preparation and different solution. Effect of polyethylene glycol addition on surface activity of the system was studied. Surface activity of phospholipids was insignificant. Surface tension decreased with increasing concentration and molecular weight of polyethylene glycol in the system. Effect of different atmosphere and increased temperature showed no substantial trend. It emerged that dynamic light scattering is not suitable for this type of samples because of high polydispersity and phase separation of the system.
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Phospholipids as the basis of biodegradable delivery systems
Burdíková, Jana ; Čeppan, Michal (referee) ; Mravec, Filip (advisor)
This thesis is focused on investigation of phospholipid-hyaluronan system. First, appropriate method for preparation of bulk solution of phospholipid/lipid and suitable fluorescence probe were chosen. Sonification was selected as a method for preparation of bulk solution and pyrene was chosen as a fluorescence probe. From the group of phospholipids lecithin was selected. Next to phospholipid, lipid with no phosphate group (DPTAP) was utilized for comparison, alternatively a mixture of lipid (DPTAP) and phospholipid (DPPC). Instead of hyaluronan another polyelectrolytes (sodium polystyrene sulfonate, sodium alginate) were used too. Measurements were performed in water environment and in phosphate buffer saline (PBS). All investigation was accomplished by fluorescence spectroscopy and dynamic light scattering.
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Study of surface tension of systems applied in ultrasonography.
Říkovská, Klára ; Pekař, Miloslav (referee) ; Mravec, Filip (advisor)
Surface tension of sonography systems was investigated using several experiments. These experiments were comprised of measurements of surface tension using BPA-800P tensiometer. The influence of surface tension of commercial substance SonoVue®, which contains in its structure two types of phospholipids, was studied more detailed. Other phospholipids were studied to comparison with SonoVue®. All substances were dissolved in saline (0,15 M NaCl). Effect of gas type on microbubbles formation and surface tension was investigated. Some samples were studied using du Nüy ring method. It was found that gas constructing the microbubbles (air or SF6) has no impact to the surface tension value. Production of foam on the surface of solutions has an impact on the value of the surface tension. This foam degreases the surface tension. Gas pressure is significant to comparison of measured data.
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