An eco-friendly photo-responsive hyaluronic acid-based supramolecular polysaccharide hybrid hydrogels for plant growth regulation and heavy metal ions adsorption.

Agrochemicals are widely used in agricultural production, but they may cause agrochemicals residues and environmental pollution. Polysaccharide-based materials have emerged as a promising biopolymer carrier for agrochemicals delivery. Herein, an eco-friendly, photo-responsive supramolecular polysaccharide hybrid hydrogels (HA-AAP-Guano-CD@LP) was constructed from arylazopyrazole-modified hyaluronic acid (HA-AAP), guanidinium functionalized ß-cyclodextrin (Guano-CD), and laponite clay (LP) via synergistic host-guest and electrostatic interactions, which could realize the controlled release of plant growth regulators such as naphthalene acetic acid (NAA) and gibberellin (GA) and promote the growth of Chinese cabbage and alfalfa. More interestingly, after releasing the cargo, the hydrogels could be used to capture heavy metal ions via strong complexation between the ions and carboxyl groups. This polysaccharide-based supramolecular hybrid hydrogels may provide a new strategy to realize the precision agriculture by the controlled delivery of plant growth regulators and synergetic adsorption of pollutants.

Fluorescent Supramolecular Assembly with Coronene Centers for Controlled DNA Condensation and Drug Delivery.

A multifunctional supramolecular assembly was successfully constructed by the host-guest complexation of doubly positively charged adamantane (ADA) with ß-CD-modified hexabenzocoronene and the π-stacking of coronene with mitoxantrone, which was characterized by transmission electron microscopy, scanning electron microscopy, dynamic light-scattering, and zeta potential experiments. Possessing a small size and rigid backbone coronene center, the water-soluble biocompatible supramolecular assembly has intracellular imaging abilities. Moreover, after the ester group of ADA was hydrolyzed into a carboxyl group, the positively charged quaternary amine strand converted into a zwitterion structure, which realized the controlled plasmid DNA binding and release. Besides, the cytotoxicity experiments showed that the supramolecular assembly possesses slightly lower toxicity and a slightly higher anticancer activity than free drug. We believe that this work might present a convenient method for synergetic cancer treatment.