Self-Healable, Injectable, and Conductive Supramolecular Eutectogel for the Encapsulation and Sustained Release of the Anticancer Drug Curcumin

The intriguing properties such as high environmental compatibility of supramolecular gels made solely through reversible noncovalent interactions are of recent interest. To offer proof of concept for the new-age sustainable materials, herein we have designed the self-healable, injectable, and ionic conductive supramolecular eutectogel in natural deep eutectic solvent (NADES). The studied eutectogels were prepared by dissolving the pharmaceutically active cetylpyridinium chloride (C16PyCl) and cetylpyridinium bromide (C16PyBr) in the NADES. The NADES was formed by interacting choline chloride (ChCl) with mono-, di-, and trimeric acids, i.e., formic acid (FA), oxalic acid (OA), and citric acid (CA) through hydrogen bonding. The gelation kinetics of the eutectogel was assessed using turbidity measurement as a function of time, whereas the morphology and mechanical properties were assessed using scanning electron microscopy (SEM) and rheology. To further verify the shape and size of the aggregate within the eutectogel, small angle neutron scattering (SANS) was performed. The eutectogel offers excellent self-healing, injectable, and ionic conductive properties as well as excellent antimicrobial properties, and offers high encapsulation efficiency for curcumin. The sustained release characteristics and release kinetics of curcumin was also investigated. Gel phases, in particular, show high colloidal forces, which, along with their environmentally benign nature, make them a great candidate not only for biomedical applications but also for the industries that require high performance with minimal environmental impact.