Abstract
Nanotechnology is a diverse field with applications across all sectors, including biomedical sciences. While it was propelled into the spotlight because of the use of lipid- based nanotechnology for the COVID mRNA vaccines, this field has been thoroughly researched for decades. While the mRNA vaccines many are familiar with had no need for tissue or receptor specific targeting, there are many biomedical applications that require the ability to localize to certain tissues or molecules. In this work, the utilization of peptide and protein ligands to specifically target certain cells or cell markers was studied in applications in therapeutics and diagnostics. The use of biological targeting ligands enables high specificity and biocompatibility, and peptides and antibody-mimetic proteins such as affibodies have the advantage of keeping the overall molecule size very small.
Specifically, three different applications of nanotechnology utilizing biological targeting ligands was explored. In one study, a polyamidoamine dendrimer-based nanoparticle was modified with peptides that targeted skeletal muscle cells and improved intracellular delivery in order to deliver a therapeutic gene for muscular dystrophy treatment. In another study, dendrimer nanocarriers were used with EGFR-targeting affibodies to localize bioluminescent proteins for in vivo imaging of pancreatic cancer cells, identifying both localized and metastatic disease. In a last study, a PD-L1-targeting affibody fused to a bioluminescent protein was used for detection of nanoscale extracellular vesicles known as exosomes. As opposed to using a synthetic nanocarrier, the third study involved using the bioluminescent fusion protein as a standalone nanoscale molecule capable of identifying specific receptors. In all studies, functional peptides or small antibody-mimetic proteins were utilized to target specific tissues, cells, or receptors for diverse biomedical applications. This work highlights some of the many advantages of biological targeting ligands for nanotechnology applications in medicine.