Self-healing polymers containing nanomaterials for biomedical engineering applications: A review

Materials that can recover the function of lost or damaged parts, called self-healing materials, have attracted attention due to their wide usage in different fields such as water refinery, coatings, robotics, and especially, biomedical applications. Depending on whether the self-healing component is added to the polymer or is inherent to the polymeric matrix, the self-healing properties of the polymeric materials can be classified into extrinsic and intrinsic self-healing. Hydrogels are one of the most used polymers in self-healing applications for various purposes, including tissue engineering, drug delivery, etc. Nanoparticles can endow some essential features to hydrogels, such as improving mechanical properties, more efficient healing ability, conductivity, and antibacterial and magnetic features. In the current study, various biomedical applications of self-healing polymers using nanoparticles are discussed in detail, showing the impact of addition of nanoparticles. Perfect antibacterial properties with the addition of copper sulfide or silver nanoparticles were achieved. In addition, enhancing compression modulus up to three times and endowing conductivity to the hydrogel as the effect of carbon nanotube addition and better mechanical properties caused by graphene oxide and iron oxide nanoparticles were reported. These are just a few examples of the results achieved by adding nanoparticles to the self-healing polymers described in this study.