| dc.description.abstract | Nanoparticles (NPs) are particles within the size range of 1-100 nm with distinctive surface structures that can act as transport particles of numerous substances. These properties allow for applications in a variety of fields, from industry to biomedicine. Lipid-based particles such as liposomes and lipid nanoparticles (LNPs) are becoming important because of their ability to transport nucleic acids that otherwise would be problematic to deliver as naked molecules. This is especially important in the field of drug delivery, as NPs can increase efficiency and decrease toxicity in the body. Safe transport of therapeutic molecules like mRNA and siRNA is fundamental in the development of new vaccines and drugs, making NPs an exciting and important prospect in drug delivery, cancer research, and gene therapy.
Much research is devoted to the further development of lipid-based NPs. To achieve this, new material components will have to be tested. One challenge that scientists face is that the biodistribution of these NPs is difficult to view in vivo when using mice as an animal model. For this reason, using zebrafish is an excellent alternative. Zebrafish have high fertility, rapid development, and most importantly, a transparent vertebrate system that allows for real-time observation of NPs in the bloodstream.
With this thesis, we wanted to observe the behaviour of lipid-based NPs by injecting liposomes into zebrafish. Liposomes were made in the laboratory and filtered to sizes of 200 nm and 1000 nm. The biodistribution of liposomes was studied by using ATTO550 as a fluorescent dye and confocal microscopy to create an image that showed the liposomes in the zebrafish vascular system.
The main findings were that liposomes of both sizes were still circulating in the zebrafish four hours after injection. It was also possible to observe bioaccumulation in some cells, likely blood resident macrophages. Given that liposomes are very similar to other lipid-based NPs, this could suggest that other lipid-based NPs would also show highly comparable behaviour in zebrafish, and possibly in humans. This relation indicates that NPs are suitable drug delivery systems that allow the slow release of drugs. | |