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.