Zhang Xiaoxuan, Chen Guopu, Yu Yunru, Sun Lingyu, Zhao Yuanjin
Department of Rheumatology and Immunology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing 210008, China.
State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China.
Research (Wash D C). 2020 May 8;2020:3672120. doi: 10.34133/2020/3672120. eCollection 2020.
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 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 suction-cup-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.
由于微针具有无痛、无创且高效的药物递送方式，它们在各个医学领域中引起了越来越多的关注。然而，这些微针在不同表皮位置和环境中的实际应用仍然受到其低粘附性和抗菌活性差的限制。在此，受贻贝足丝和章鱼触手的抗菌策略及粘附机制的启发，我们开发了具有多功能粘附和抗菌能力的分级微针。以聚多巴胺水凝胶为微针基体，并在每个微针周围环绕一圈吸盘结构的凹腔，所制备的微针能够很好地贴合皮肤；在干燥、潮湿和湿润环境中保持较强的粘附力；并且在被分成两部分后能够实现自我修复。此外，由于在水凝胶尖端和聚多巴胺基体中均负载了多粘菌素，这些微针在储存和使用过程中具有优异的抵抗常见细菌的能力。我们已经证明，这些微针不仅在应用于指关节时表现出优异的粘附力和理想的抗菌活性，而且在药物缓释和骨关节炎大鼠模型治疗方面也表现良好。这些结果表明，受生物启发的多功能微针将突破传统方法的限制，成为通用透皮给药系统的理想候选者。
