Liposomes are small, spherical vesicles containing at least one lipid bilayer. They can be made from natural or synthetic phospholipids. The building blocks of liposomes, lipids, are amphiphilic molecules, meaning that liposomes can entrap both hydrophilic and lipophilic molecules. They have great utility in pharmacy, as they serve as carriers for many active substances. In the thesis, we prepared three liposomal mixtures, where soya lecithin was the main lipid source. The first mixture contained soya lecithin, water and glycerol, the second mixture contained chia seed extract instead of water and the last mixture contained hemp seed extract instead of water. Before analysis, the first mixture was diluted with water and with a mixture of water and glycerol, while the other two mixtures were diluted with water only.
The diameter, concentration and polydispersity of the vesicles were determined using the dynamic light scattering method (DLS) and the interferometric light microscopy (ILM; instrument Videodrop) method, and we found that the use of different solvents to dilute the first mixture affects all three parameters. When the mixture was diluted with water, the formed particles had larger diameters, lower total concentration and a narrower size distribution. These methods and the spectrophotometric method (instrument Nanodrop) were also used to observe how the addition of chia or hemp seed extracts affects the size and composition of the vesicles. The mixture containing chia seed extract had larger particles compared to the mixture containing hemp seed extract. The same was found when measuring the seed extracts, where the particles in the chia seed extract were about 2 times larger than those in the hemp seed extract.
By measuring the absorbance at specific wavelengths using the spectrophotometric method, we found that hemp seeds and the mixture containing hemp seed extract had a higher content of organic compounds, while chia seeds and the mixture containing chia seed extract had a higher content of nucleic acids and proteins. However, by observing the liposomes under an optical microscope, we found that the liposomes differed in shape, size and lamellarity between the three mixtures and in the two different media (washout and foam of chia or hemp seeds).
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