Abstract
For effective treatment of diseases such as cancer or fibrosis, it is essential to deliver therapeutic agents such as drugs to the diseased tissue, but these diseased sites are surrounded by a dense network of fibers, cells, and proteins known as the extracellular matrix (ECM). The ECM forms a barrier between the diseased cells and blood circulation, the main route of administration of most drug delivery nanoparticles. Hence, a stiff ECM impedes drug delivery by limiting the transport of drugs to the diseased tissue. The use of self-propelled particles (SPPs) that can move in a directional manner with the application of physical or chemical forces can help in increasing the drug delivery efficiency. Here, we provide a comprehensive look at the current ECM models in use to mimic the in vivo diseased states, the different types of SPPs that have been experimentally tested in these models, and suggest directions for future research toward clinical translation of SPPs in diverse biomedical settings.
Highlights
Penetration and Payload Delivery inThe extracellular matrix (ECM) is a complex three-dimensional network of proteins, sugars, cells, and biomolecules [1] that provides support to biological tissue and aids cellular processes [2] such as differentiation and signaling [3,4]
Our primary focus is on experimental demonstrations of self-propelled particles (SPPs) designs that have been shown to effectively move in models of the ECM; theoretical investigations have the potential to inform the design of future microswimmers, a topic we revisit in Section 4, which identifies open questions and suggests future research directions
Hyaluronic acid (HA) is a naturally occurring linear polysaccharide with repeating units of D-glucuronic acid and N-acetyl-D-glucosamine linked by glycosidic bonds [90], which is found in natural ECM as well as biofilms [91], and can be readily modified to create hydrogels
Summary
The extracellular matrix (ECM) is a complex three-dimensional network of proteins, sugars, cells, and biomolecules [1] that provides support to biological tissue and aids cellular processes [2] such as differentiation and signaling [3,4]. The ECM is a dynamic environment that often undergoes remodeling and plays an instructive role in regulating tissue homeostasis [5] In diseases such as cancer [2,6] or fibrosis, which is implicated in over 45% of deaths in the developed world [7], the ECM undergoes abnormal growth or repair, which can cause it to become dense and stiff [8], forming a mechanical and biochemical barrier for drug delivery systems since the ECM limits the transport of drugs to diseased cells [9]. Better patient outcomes necessitate improved penetration of drug delivery systems through the ECM [15] Conventional nanocarriers, such as liposomes [16,17], polymeric nanoparticles [18,19], or metallic nanoparticles [20,21], rely on passive diffusion for transport through the ECM and so cannot penetrate diseased ECM effectively. One potential way to realize this vision is to use self-propelled particles (SPPs) as
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
