Hierarchically Templated Synthesis of 3D-Printed Crosslinked Cyclodextrins for Lycopene Harvesting.

Plants produce a wide range of bioactive phytochemicals, such as antioxidants and vitamins, which play crucial roles in aging prevention, inflammation reduction, and reducing the risk of cancer. Selectively harvesting these phytochemicals, such as lycopene, from tomatoes through the adsorption method is cost-effective and energy efficient. In this work, a templated synthesis of 3D-printed crosslinked cyclodextrin polymers featuring nanotubular structures for highly selective lycopene harvesting is reported.

Study on the Friction and Wear Properties of PEEK against Cortical Bone Tissue Under Different Lubricating Conditions.

The tribological behavior between orthopedic implants and cortical bone is important but usually neglected. Poly(ether-ether-ketone) (PEEK) is a promising material for orthopedic applications. To further understand and improve the interfacial tribological properties between PEEK implant and host bone tissue, a PEEK-cortical bone tribo-pair is designed and fabricated.

Enhanced Bacterial-Infected Wound Healing by Nitric Oxide-Releasing Topological Supramolecular Nanocarriers with Self-Optimized Cooperative Multi-Point Anchoring.

Polymeric systems that provide cationic charges or biocide-release therapeutics are used to treat the bacteria-infected wound. However, most antibacterial polymers based on topologies with restricted molecular dynamics still do not satisfy the clinical requirements due to their limited antibacterial efficacy at safe concentrations in vivo. Here a NO-releasing topological supramolecular nanocarrier with rotatable and slidable molecular entities is reported to provide conformational freedom to promote the interactions between the carrier and the pathogenic microbes, hence greatly improving the antibacterial performance.

Conductive and anti-freezing hydrogels constructed by pseudo-slide-ring networks.

Stretchable, tough, and anti-freezing hydrogels were prepared using partially carboxymethylated polyrotaxanes and polyacrylamides. The carboxylic acid groups of α-cyclodextrins in the polyrotaxane and the amide groups in polyacrylamide are hydrogen-bonded, affording a pseudo-slide-ring network, greatly enhancing the hydrogels' macroscale mechanical properties, anti-freezing features, and electrical conductivity for the fabrication of a cold-temperature strain sensor.

An Integrated Design of a Polypseudorotaxane-Based Sea Cucumber Mimic.

The development of integrated systems that mimic the multi-stage stiffness change of marine animals such as the sea cucumber requires the design of molecularly tailored structures. Herein, we used an integrated biomimicry design to fabricate a sea cucumber mimic using sidechain polypseudorotaxanes with tunable nano-to-macroscale properties. A series of polyethylene glycol (PEG)-based sidechain copolymers were synthesized to form sidechain polypseudorotaxanes with α-cyclodextrins (α-CDs).

Advanced Polymer Designs for Direct-Ink-Write 3D Printing.

The rapid development of additive manufacturing techniques, also known as three-dimensional (3D) printing, is driving innovations in polymer chemistry, materials science, and engineering. Among current 3D printing techniques, direct ink writing (DIW) employs viscoelastic materials as inks, which are capable of constructing sophisticated 3D architectures at ambient conditions. In this perspective, polymer designs that meet the rheological requirements for direct ink writing are outlined and successful examples are summarized, which include the development of polymer micelles, co-assembled hydrogels, supramolecularly cross-linked systems, polymer liquids with microcrystalline domains, and hydrogels with dynamic covalent cross-links.

Hierarchical-Coassembly-Enabled 3D-Printing of Homogeneous and Heterogeneous Covalent Organic Frameworks.

Covalent organic frameworks (COFs) are crystalline polymers with permanent porosity. They are usually synthesized as micrometer-sized powders or two-dimensional thin films and membranes for applications in molecular storage, separation, and catalysis. In this work, we report a general method to integrate COFs with imine or β-ketoenamine linkages into three-dimensional (3D)-printing materials.

Hierarchical Co-Assembly Enhanced Direct Ink Writing.

Integrating intelligent molecular systems into 3D printing materials and transforming their molecular functions to the macroscale with controlled superstructures will unleash great potential for the development of smart materials. Compared to macromolecular 3D printing materials, self-assembled small-molecule-based 3D printing materials are very rare owing to the difficulties of facilitating 3D printability as well as preserving their molecular functions macroscopically. Herein, we report a general approach for the integration of functional small molecules into 3D printing materials for direct ink writing through the introduction of a supramolecular template.

Ring Shuttling Controls Macroscopic Motion in a Three-Dimensional Printed Polyrotaxane Monolith.

Amplification of molecular motions into the macroscopic world has great potential in the development of smart materials. Demonstrated here is an approach that integrates mechanically interlocked molecules into complex three-dimensional (3D) architectures by direct-write 3D printing. The design and synthesis of polypseudorotaxane hydrogels, which are composed of α-cyclodextrins and poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymers, and their subsequent fabrication into polyrotaxane-based lattice cubes by 3D printing followed by post-printing polymerization are reported.

Injectable supramolecular hydrogel formed from α-cyclodextrin and PEGylated arginine-functionalized poly(l-lysine) dendron for sustained MMP-9 shRNA plasmid delivery.

Unlabelled: Hydrogels have attracted much attention in cancer therapy and tissue engineering due to their sustained gene delivery ability. To obtain an injectable and high-efficiency gene delivery hydrogel, methoxypolyethylene glycol (MPEG) was used to conjugate with the arginine-functionalized poly(l-lysine) dendron (PLLD-Arg) by click reaction, and then the synthesized MPEG-PLLD-Arg interacted with α-cyclodextrin (α-CD) to form the supramolecular hydrogel by the host-guest interaction. The gelation dynamics, hydrogel strength and shear viscosity could be modulated by α-CD content in the hydrogel.

A star-shaped porphyrin-arginine functionalized poly(L-lysine) copolymer for photo-enhanced drug and gene co-delivery.

The co-delivery of drug and gene has become the primary strategy in cancer and other disease therapy. To co-deliver hydrophobic drug and functional gene efficiently into tumor cells, a star-shaped copolymer (PP-PLLD-Arg) with a photochemical internalization effect consisting of a porphyrin (PP) core and arginine-functionalized poly(L-lysine) dendron (PLLD-Arg) arms has been designed, and used to co-deliver docetaxel (DOC) and MMP-9 shRNA plasmid for nasopharyngeal cancer therapy. It was found that PP-PLLD-Arg/MMP-9 nanocomplex showed the photo-enhanced gene transfection efficiency in vitro, and could mediate a significant reduce of MMP-9 protein expression in HNE-1 cells.

Photoenhanced gene transfection by a star-shaped polymer consisting of a porphyrin core and poly(L-lysine) dendron arms.

A star-shaped polymer (PP-PLLD) consisting of a porphyrin (PP) core and poly(L-lysine) dendron arms (PLLD) is synthesized by the click reaction, and its ability to deliver pEGFP is investigated in this paper. It is found that PP-PLLD has a good buffer capacity and can form compact complexes with pEGFP. In vitro assay indicates that PP-PLLD shows photoenhanced gene transfection efficiency.