New strategies for multifunctional antibacterial materials

Licentiate thesis, 2023

Healthcare-associated infections (HAI) are responsible for significant financial and human costs in healthcare systems. Therefore, a substantial amount of research has been devoted to developing biopolymer-based strategies that prevent bacterial attachment and biofilm formation on surfaces. Gelatin hydrogels have been used in the last decades for different biomedical applications due to the excellent biocompatibility, easy processability, bioactivities to mimic the extracellular matrix (ECM). However, their poor mechanical properties and thermal stability limited their potential applications. Herein, a facile and economical approach of introducing dopamine and [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA) via in situ synthesis into gelatin hydrogels with the existence of ZnSO4 was applied to overcome these disadvantages. This fabrication method allows the obtaining of gelatin-based hydrogels with fatigue resistance and mechanical stability from -100 to 80 ℃. Moreover, the hydrogels showed adhesive, self-healing, electrical and excellent antibacterial properties leading to their potential use as wearable monitoring sensors and antibacterial coatings. In particular, the hydrogels showed adhesion to various types of surfaces such as paper, skin, wood, plastic, rubber and steel, as well as 99.99% and 100% of antibacterial efficiency against Gram-positive and Gram-negative bacteria respectively. The results indicate widespread applications of the new hydrogels in many biomedical areas.