writer：Weijiang Yu, ? Jieze Shen,? Chong Ji, Peng Zhang, Hao Chang, Youxiang Wang * and Jian Ji *
keywords：Microneedle, Shape Memory Polymers, Penetration
source：期刊
specific source：Materials Horizons
Issue time：2023年
The use of microneedle (MN) systems has the potential to benefit a
wide range of biomedical applications but is hindered by poorly
controlled insertion. Herein, a novel MN penetration strategy is
presented, which utilizes the recovery stress of near-infrared lighttriggered
shape memory polymers (SMPs) to drive MN insertion.
This strategy enables force control over MN application with the
precision of 15 mN through tunable light intensity. The pre-stretch
strain of SMP can be further predetermined to provide a safety
margin on penetration depth. Using this strategy, we demonstrate
that MNcan precisely insert into the stromal layer of the rabbit cornea.
Additionally, the MN unit array allows programmable insertion for
multistage and patterned payload delivery. This proof-of-concept
strategy promises remotely, precisely, and spatiotemporally controlled
MN insertion, which may inspire the further development of
MN-related applications.