Meta-DNA Strand Displacement for Sub-Micron-Scale Autonomous Reconfiguration.

Dynamic molecular interactions in chemical reaction networks lead to complex behaviors in living systems. Whereas recent advances in programming DNA molecular reactions have reached a high level of complexity at molecular and nanometer scales, achieving programmable autonomous behavior at submicron or even larger scales remains challenging. Here, we present a mechanism of meta-DNA strand displacement reactions (M-SDRs) that is mediated solely by meta-toehold (M-toehold) using versatile submicron building blocks of meta-DNA (M-DNA).

Janus Nanoparticle Coupled Double-Network Hydrogel.

For double network (DN) hydrogels, their performance can be tuned by adjusting the interaction between their two networks. A novel DN hydrogel toughening approach is proposed by employing Janus nanoparticles (JNs) as crosslinkers to gain a conjoined-network hydrogel. First, a kind of JNs modified by amino groups and quaternary ammonium salt is synthesized, named R N -JN-NH .

Nanogel Multienzyme Mimics Synthesized by Biocatalytic ATRP and Metal Coordination for Bioresponsive Fluorescence Imaging.

The design of enzyme mimics from stable and nonprotein systems is especially attractive for applications in highly specific cancer diagnosis and treatment, and it has become an emerging field in recent years. Herein, metal crosslinked polymeric nanogels (MPGs) were prepared using Fe ion coordinated biocompatible acryloyl-lysine polymer brushes obtained from an enzyme-catalyzed atomic transfer radical polymerization (ATRPase) method. The monoatomic and highly dispersed Fe ions in the MPGs serve as efficient crosslinkers of the gel network, and also as active centers of multienzyme mimics of superoxide dismutase (SOD) and peroxidase (POD).

Strength-tunable printing of xanthan gum hydrogel via enzymatic polymerization and amide bioconjugation.

Amide bioconjugation and interfacial enzyme polymerization are designed to provide a general strategy for regulating the mechanical strength (storage modulus from 3 kPa to 100 kPa) of printable hydrogel inks.

One-Step Nanosurface Self-Assembly of d-Peptides Renders Bubble-Free Ultrasound Theranostics.

The surface bioinspired modification of particles and films is a mainstream direction in biomaterial design and application. The interfacial coating of extracellular-matrix-like hydrogel can endow functional inorganic nanoparticles high circulation stability and biocompatibility but remains challenging due to large surface tension difference between organic gelators and solid nanosurfaces. Herein, the supramolecular hydrogel of NapGFFK around gold nanorods (Au NRs-Gel) has been constructed by the amidation-grafting modification and the protonation-induced interface-assistant assembly of peptide precursors.