Polydopamine-intercalated montmorillonite to mitigate polymerization inhibition for preparation of photothermal antibacterial and hemostatic hydrogel

The mechanical properties of hydrogels with in situ introduced polydopamine (PDA) will always be unsatisfactory owing to the polymerization inhibition of the catechol structure. Therefore, it is necessary to find a way to mitigate the inhibition. In this work, PDA-inserted montmorillonite (MMT) was first prepared. The micro-spacing of the MMT nanolayers limited the oxygen content which prevented the complete oxidation of the dopamine adsorbed between the MMT nanosheet layers and retained the catechol moiety. Then, polydopamine montmorillonite polyacrylamide (PMP) hydrogel was prepared under green LED irradiation. The hydrogel exhibited excellent mechanical properties and adhesive strength, as well as excellent photothermal properties and antimicrobial ability. After irradiation by NIR laser, the PMP hydrogel can be heated up and maintained at 50 ℃ within 2 min, and the antimicrobial rate reached 98 %. Meanwhile, PMP hydrogel presents excellent biocompatibility and hemostatic ability. Therefore, PMP hydrogel has a great potential in the field of photothermal therapy and hemostasis.