Multistimuli Responsive Supramolecular Polymeric Nanoparticles Formed by Calixpyridinium and Chondroitin 4-Sulfate

We have successfully constructed multistimuli responsive supramolecular polymeric nanoparticles based on the complexation of calixpyridinium with polyanionic chondroitin 4-sulfate. The nanoparticles are disassembled upon increasing pH from 6 to 9, while a pH-responsive morphological conversion from spherical nanoparticles to nanorods is observed upon decreasing pH from 6 to 2. Adding a competitive guest can also disrupt the assembly, representing the host-guest inclusion response. Interestingly, an unexpected hyaluronidase-responsive morphological conversion from spherical nanoparticles to wire-like suprastructures rather than disassembly is also observed, as a result of the hyaluronidase-induced cleavage of chondroitin 4-sulfate. The multistimuli responsive morphological conversion property with various dimensions, along with the facile preparation, will make this supramolecular polymeric assembly approach well-suitable for a variety of important material applications.