Adjusting the length of supramolecular polymer bottlebrushes by top-down approaches

Abstract

Controlling the length of one-dimensional (1D) polymer nanostructures remains a key challenge on the way toward the applications of these structures. Here, we demonstrate that top-down processing facilitates a straightforward adjustment of the length of polyethylene oxide (PEO)-based supramolecular polymer bottlebrushes (SPBs) in aqueous solutions. These cylindrical structures self-assemble via directional hydrogen bonds formed by benzenetrisurea (BTU) or benzenetrispeptide (BTP) motifs located within the hydrophobic core of the fiber. A slow transition from different organic solvents to water leads first to the formation of µm-long fibers, which can subsequently be fragmented by ultrasonication or dual asymmetric centrifugation. The latter allows for a better adjustment of applied shear stresses, and thus enables access to differently sized fragments depending on time and rotation rate. Extended sonication and scission analysis further allowed an estimation of tensile strengths of around 16 MPa for both the BTU and BTP systems. In combination with the high kinetic stability of these SPBs, the applied top-down methods represent an easily implementable technique toward 1D polymer nanostructures with an adjustable length in the range of interest for perspective biomedical applications.

Precision polymer nanofibers with a responsive polyelectrolyte corona designed as a modular, functionalizable nanomedicine platform

“…This would yield low dispersity seed nanofibers in one step in a manner analogous to that used for supramolecular polymers. 93,94 The single-step formation of seed nanofibers has been previously reported for polyselenophene as the coreforming block, 95 however sonication was not utilized in this process. P1 unimer was dissolved in THF/MeOH (5 : 95 v/v) and immediately sonicated for 3 h between 0 °C and 23 °C, and aged overnight.…”

Elucidating the role of multivalency, shape, size and functional group density on antibacterial activity of diversified supramolecular nanostructures enabled by templated assembly

“…As these cylinders are formed through relatively weak noncovalent bonds, they can be broken into smaller cylinders using external forces, such as ultrasonication. 52,53 Here, we generated the desired length cylinders by adjusting the sonication time ( As the nanoparticles showed distinct growth inhibition propensities in the liquid cultures, we next assessed their antibacterial activity on…”

“…As these cylinders are formed through relatively weak noncovalent bonds, they can be broken into smaller cylinders using external forces, such as ultrasonication. 52,53 Here, we generated the desired length cylinders by adjusting the sonication time (Fig. 2b, and Fig.…”