Reducing Agent Triggered Templated Synthesis of Dynamic Covalent Poly(disulfide)s Nanonetwork: Remarkable Tuning in Noncovalent Encapsulation Stabilities and Cargo Release

Abstract

Here, we demonstrated a new methodology for the templated synthesis of cross-linked poly(disulfide)s based dynamic covalent nanonetwork as highly stable potential delivery vehicle in the field of chemotherapeutic applications. The synthesis is carried out by the treatment of nanoaggregate of biomass-derived lipoic acid based amphiphilic monomer with reducing agent at room temperature in open air condition and aqueous medium. The hydrodynamic diameter of the naoaggregate is found to be ~130 nm as probed by dynamic light scattering experiment. The control over cross-linking density is achieved by varying the ratio of monomer to reducing agent. The crosslinking percentage varied from ~13% to ~100%. This gives the opportunity of fine-tuning the stability of the nanocarrier itself, noncovalent encapsulation stabilities and kinetics of cargo release, which are highly relevant in the field of drug delivery applications. For highly crosslinked nanonetwork, in simulated redox condition of cancer cell, ~80% guest release was noted from the nanonetwork in a sustained manner. The controlled depolymerization of the polymer is accomplished by the use of specific mol% of the same reducing agent. Finally, the reversibility and recyclability of the poly(disulfide)s to the monomeric form is achieved by the treatment of the polymer with the external thiol in presence of an organic base.