Spatial control over catalyst positioning on biodegradable polymeric nanomotors

Abstract

Scientists over the world are inspired by biological nanomotors and try to mimic these complex structures. In recent years multiple nanomotors have been created for various fields, such as biomedical applications or environmental remediation, which require a different design both in terms of size and shape, as well as material properties. So far, only relatively simple designs for synthetic nanomotors have been reported. Herein, we report an approach to create biodegradable polymeric nanomotors with a multivalent design. PEG-PDLLA (poly(ethylene glycol)-b-poly(D,L-lactide)) stomatocytes with azide handles were created that were selectively reduced on the outside surface by TCEP (tris(2-carboxyethyl)phosphine) functionalized beads. Thereby, two different functional handles were created, both on the inner and outer surface of the stomatocytes, providing spatial control for catalyst positioning. Enzymes were coupled on the inside of the stomatocyte to induce motion in the presence of fuel, while fluorophores and other molecules can be attached on the outside.

LipoBots: Using Liposomal Vesicles as Protective Shell of Urease‐Based Nanomotors

“…Thus, entire libraries of enzyme/biomolecule (engine/fuel) combinations could be designed for specific on-demand applications. [35][36][37] Enzymes used in catalytic nanomotors include urease, [38][39][40][41][42][43][44] acetylcholine esterase, [44] glucose-oxidase, [39,44,45] lipase, [46] catalase, [39,42,[47][48][49][50] and combinations thereof, all which can induce propulsion of various nano-and/or microparticles. Nevertheless, the use of enzymepowered nanomotors in vivo demands additional application requirements beyond biocompatibility and fuel bioavailability.…”

Enzyme catalysis powered micro/nanomotors for biomedical applications

“…The stomach of the stomatocytes was functionalized with GOx and catalase, showing propelled motion with speeds reaching up to 15.8 mm s À1 in the presence of glucose. 129 The same group also fabricated asymmetric hydrogel based micromotors composed of dextran and poly(ethylene glycol) diacrylate (PEGDA) with entrapped catalase (Fig. 4c).…”

Recent Advances in the Synthesis and Application of Polymer Compartments for Catalysis

“…However, in the case of ATP sensitive stomatocytes, the ATP concentration and its conversion to AMP served as a time-programmed valve controlling the accessibility of the Pt catalyst and the lifetime of movement speed. Using a similar synthetic strategy, the cup shape of the stomatocytes also allowed selective modification of the inside and outside of the wall [ 160 ] essentially resulting in Janus nanocups [ 161 ]. For that, N 3 -PEO- b -PLA and PEO- b -PLA were synthesized by AROP and co-assembled into stomatocytes with azide functionality on the surface.…”