Requirements and properties of biomaterials for biomedical applications

Abstract During the last decades, different nanosystems have been developed to deliver therapeutic agents and improve their solubility and pharmacokinetic properties, reducing their systemic side effects. To achieve this, nanomedicines need to be rationally designed and tailored to reach a specific site of action, modulate their biodistribution, and circumvent the biological barriers upon in-vivo administration. In this chapter, after presenting the main biological barriers that nanomedicines can face after administration, we address the parameters/strategies that should be taken into consideration when engineering nanoparticles (NPs) for biomedical applications, including the composition and physicochemical properties of NPs (e.g., size, charge, shape, and surface chemistry). Finally, we present several surface functionalization strategies for active targeting and improved stability of NPs, and stimuli-responsive approaches for a controlled release of the therapeutics at the target tissue, which can be used for different applications, including cancer therapy and immunotherapy, oral delivery, and regenerative medicine.