Towards a molecular-level understanding of the protein corona around nanoparticles - Recent advances and persisting challenges

Presently, the enormous research activities in the design and engineering of nanomaterials for biomedicine are sharply contrasted by the small number of nanomaterials in clinical use. One of the key hurdles toward biomedical applications of nanoparticles (NPs), apart from the lack of definition and batch-to-batch reproducibility of many NP preparations, is the incomplete understanding of the protein corona around NPs, which strongly affects the interactions with the biological environment. While gaps in our molecular-level knowledge of the corona are continuously being filled, the field is moving toward the design of NPs that control and even exploit the properties of the protein corona. Another important issue gaining increasing attention is a shift from in vitro to in vivo studies, which are essential for successful translation to clinical applications. This review highlights a selection of the latest developments, persistent challenges, as well as exciting new advancements.