Drug delivery carriers with therapeutic functions

Design of micro-or nanocarriers for drug delivery has primarily been focused on properties such as hydrophobicity, biodegradability, size, shape, surface charge, and toxicity, so that they can achieve opti-mal delivery with respect to drug loading, release kinetics, biodistribution, cellular uptake, and biocom-patibility. Incorporation of stimulus-sensitive moieties into the carriers would lead to "smart" delivery systems. A further evolution would be to endow the carrier with a therapeutic function such that it no longer serves as a mere passive entity to release the drug at the target tissue but can be viewed as a ther-apeutic agent in itself. In this review, we will discuss recent and ongoing efforts over the past decade to design therapeutic drug carriers that confer a biological benefit, including ROS scavenging or generating, pro-or anti-inflammatory, and immuno-evasive properties, to enhance the overall therapeutic efficacy of the delivery systems. (c) 2021 Elsevier B.V. All rights reserved.