Engineered Polymeric Materials for Biological Applications: Overcoming Challenges of the Bio–Nano Interface

Nanomedicine has generated significant interest as an alternative to conventional cancer therapy due to the ability for nanoparticles to tune cargo release. However, while nanoparticle technology has promised significant benefit, there are still limited examples of nanoparticles in clinical practice. The low translational success of nanoparticle research is due to the series of biological roadblocks that nanoparticles must migrate to be effective, including blood and plasma interactions, clearance, extravasation, and tumor penetration, through to cellular targeting, internalization, and endosomal escape. It is important to consider these roadblocks holistically in order to design more effective delivery systems. This perspective will discuss how nanoparticles can be designed to migrate each of these biological challenges and thus improve nanoparticle delivery systems in the future. In this review, we have limited the literature discussed to studies investigating the impact of polymer nanoparticle structure or composition on therapeutic delivery and associated advancements. The focus of this review is to highlight the impact of nanoparticle characteristics on the interaction with different biological barriers. More specific studies/reviews have been referenced where possible.