Morphological Transformation and Surface Engineering of Glycovesicles Driven by Bioinspired Hydrogen Bonds of Nucleobases.

Glycopolymer-based supramolecular glycoassemblies with signal-driven cascade morphological deformation and accessible surface engineering toward bioinspired functional glycomaterials have attracted much attention due to their diverse applications in fundamental and practical scenarios. Herein, we achieved the cascade morphological transformation and surface engineering of a nucleobase-containing polymeric glycovesicle through exploiting the bioinspired complementary multiple hydrogen bonds of complementary nucleobases. First, the synthesized thymine-containing glycopolymers (PGal30-b-PTAm249) are capable of self-assembling into well-defined glycovesicles. Several kinds of amphiphilic adenine-containing block copolymers with neutral, positive, and negative charges were synthesized to engineer the glycovesicles through the multiple hydrogen bonds between adenine and thymine. A cascade of morphological transformations from vesicles to ruptured vesicles with tails, to worm-like micelles, and finally to spherical micelles were observed via continuously adding the adenine-containing polymer into the thymine-containing glycovesicles. Furthermore, the surface charge properties of these glyconano-objects can be facilely regulated through incorporating various adenine-containing polymers. This work demonstrates the potential application of a unique bioinspired approach to precisely engineer the morphology and surface properties of glycovesicles for boosting their biological applications.

Fluorine-Rich Supramolecular Nano-Container Crosslinked Hydrogel for Lithium Extraction with Super-High Capacity and Extreme Selectivity.

Extraction and recovery of lithium from reserves play a critical role in the sustainable development of energy due to the explosive growth of the lithium-battery market. However, the low efficiency of extraction and recovery seriously threatens the sustainability of lithium supply. In this contribution, we fabricate a novel mechanically robust fluorine-rich hydrogel, showing highly efficient Li+ extraction from Li-containing solutions. The hydrogel was facilely fabricated by simple one-pot polymerization of supramolecular nanosheets of fluorinated monomers, acrylic acid and a small amount of chemical crosslinkers. The hydrogel exhibits a remarkable lithium adsorption capacity (Qm Li+ =122.3 mg g-1 ) and can be reused. Moreover, it can exclusively extract lithium ions from multiple co-existing metal ions. Notably, the separation of Li+ /Na+ in actual wastewater is achieved with a surprising separation factor of 153.72. The detailed characterizations as well as calculation showed that the specific coordination of Li-F plays a central role for both of the striking recovery capability and selectivity for Li+ . Furthermore, an artificial device was constructed, displaying high efficiency of extracting lithium in various complex actual lithium-containing wastewater. This work provides a new and promising avenue for the efficient extraction and recovery of lithium resource from complex lithium-containing solutions.

Polyacrylamide-Based Block Copolymer Bearing Pyridine Groups Shows Unexpected Salt-Induced LCST Behavior.

Thermal-responsive block copolymers are a special type of macromolecule that exhibit a wide range of applications in various fields. In this contribution, we report a new type of polyacrylamide-based block copolymer bearing pyridine groups of polyethylene glycol-block-poly(N-(2-methylpyridine)-acrylamide; Px) that display distinct salt-induced lower critical solution temperature (LCST) behavior. Unexpectedly, the phase-transition mechanism of the salt-induced LCST behavior of Px block copolymers is different from that of the reported LCST-featured analogues. Moreover, their thermo-responsive behavior can be significantly regulated by several parameters such as salt species and concentration, urea, polymerization degree, polymer concentration and pH values. This unique thermal behavior of pyridine-containing block copolymers provides a new avenue for the fabrication of smart polymer materials with potential applications in biomedicine.