A Simple Photochemical Route to Hyperbranched Polymers by Using Photolatent Inimer

Preparation and Self-Assembly of pH-Responsive Hyperbranched Polymer Peptide Hybrid Materials

In recent years, the coupling of structurally and functionally controllable polymers with biologically active peptide materials to obtain polymer-peptide hybrids with excellent properties and biocompatibility has led to important research progress in the field of polymers. In this study, a pH-responsive hyperbranched polymer hPDPA was prepared by combining atom transfer radical polymerization (ATRP) with self-condensation vinyl polymerization (SCVP) using a three-component reaction of Passerini to obtain a monomeric initiator ABMA containing functional groups. The pH-responsive polymer peptide hybrids hPDPA/PArg/HA were obtained by using the molecular recognition of polyarginine (β-CD-PArg) peptide modified with β-cyclodextrin (β-CD) on the hyperbranched polymer, followed by the electrostatic adsorption of hyaluronic acid (HA). The two hybrid materials, h₁PDPA/PArg₁₂/HA and h₂PDPA/PArg₈/HA could self-assemble to form vesicles with narrow dispersion and nanoscale dimensions in phosphate-buffered (PB) at pH = 7.4. The assemblies exhibited low toxicity as drug carriers of β-lapachone (β-lapa), and the synergistic therapy based on ROS and NO generated by β-lapa had significant inhibitory effects on cancer cells.

One-step synthesis of sequence-controlled multiblock polymers with up to 11 segments from monomer mixture

Switchable polymerization holds considerable potential for the synthesis of highly sequence-controlled multiblock. To date, this method has been limited to three-component systems, which enables the straightforward synthesis of multiblock polymers with less than five blocks. Herein, we report a self-switchable polymerization enabled by simple alkali metal carboxylate catalysts that directly polymerize six-component mixtures into multiblock polymers consisting of up to 11 blocks. Without an external trigger, the catalyst polymerization spontaneously connects five catalytic cycles in an orderly manner, involving four anhydride/epoxide ring-opening copolymerizations and one L-lactide ring-opening polymerization, creating a one-step synthetic pathway. Following this autotandem catalysis, reasonable combinations of different catalytic cycles allow the direct preparation of diverse, sequence-controlled, multiblock copolymers even containing various hyperbranched architectures. This method shows considerable promise in the synthesis of sequentially and architecturally complex polymers, with high monomer sequence control that provides the potential for designing materials.