Bioinspired nanotopographical design of drug delivery systems

Effective drug delivery is important in the treatment of various biomedical conditions, ranging from autoimmune disorders to cancer and bacterial infections. Nanostructured systems can help to overcome challenges to efficient drug delivery such as poor drug distribution, inefficient penetration across biological barriers and off-target effects. The bioinspired nanotopography of drug carrier surfaces provides a physical cue to modulate their interaction with biological systems. In this Review, we discuss how naturally occurring nanotopographical systems can inspire the design of biomaterials for drug delivery. We highlight nanoscale surface modifications of drug carriers and fabrication strategies, followed by a discussion about nanotopographical biointerfaces to regulate biological functions. Key bioinspired nanotopographical functionalities include bio-adhesion, barrier remodelling, drug uptake and subcellular trafficking, cellular signalling and modulation, and antimicrobial interfaces. Finally, we provide an outlook on the future of nanotopographical applications in drug delivery, with a focus on key challenges and exciting opportunities from bench to bedside. Three-dimensional nanotopography plays a key role in the interaction of nanoscale drug delivery systems and biological components. This Review discusses bioinspired nanotopographies that can improve muco-adhesion and cyto-adhesion, drug uptake and trafficking, barrier remodelling, cellular modulation and antimicrobial activities of various drug delivery platforms.