摘要
Microneedles have attracted increasing interest among various medical fields due to their painless,noninvasive,and efficient way of drug delivery.However,practical applications of these microneedles in different epidermal locations and environments are still restricted by their low adhesion and poor antimicrobial activity.Here,inspired by the antibacterial strategy of Paenibacillus polymyxa and adhesion mechanisms of mussel byssi and octopus tentacles,we develop hierarchical microneedles with multifunctional adhesive and antibacterial abilities.With polydopamine hydrogel as the microneedle base and a loop of suctioncup-structured concave chambers encircling each microneedle,the generated microneedles can fit the skin well;keep strong adhesion in dry,moist,and wet environments;and realize self-repair after being split into two parts.Besides,as polymyxin is loaded into both the hydrogel tips and the polydopamine base,the microneedles are endowed with excellent ability to resist common bacteria during storage and usage.We have demonstrated that these microneedles not only showed excellent adhesion when applied to knuckles and ideal antibacterial activity but also performed well in drug-sustained release and treatment for the osteoarthritis rat model.These results indicate that bioinspired multifunctional microneedles will break through the limitation of traditional methods and be ideal candidates for versatile transdermal drug delivery systems.
基金
This work was supported by the National Natural Science Foundation of China(grants 61927805 and 51522302)
the Natural Science Foundation of Jiangsu(Grant no.BE2018707)
the Scientific Research Foundation of Nanjing University and Drum Tower Hospital.
