Three-Dimensional Hydrazone-Equipped Covalent Organic Frameworks as pH-Triggered Rotary Switches

Wenjuan Zhao (1) , Chengyang Yu (1) , Jie Zhao (2) , Fengqian Chen (1) , Xinyu Guan (1) , Hui S Li (1) , Bin Tang (3) , Guangtao Yu (4) , Valentin Valtchev (5) , Yushan Yan (6) , Shilun Qiu (1) , Qianrong Fang (1)

1 JLU - Jilin University
2 RIPP - Research Institute of Petroleum processing
3 Deakin University [Burwood]
4 Fujian Normal University [Fujian]
5 LCS - Laboratoire catalyse et spectrochimie
6 University of Delaware [Newark]

The properties expansion of three-dimensional (3D) functionalized covalent organic frameworks (COFs) is important for developing their potential applications. Herein, we report the first case of 3D hydrazone-based COFs as pH-triggered molecular switches and explore their application in the stimuli-responsive drug delivery system. These functionalized COFs with hydrazone groups on the channel walls were obtained via a multi-component bottom-up synthesis strategy. They exhibit a good invertibility E/Z isomerization at various pH values, confirmed by UV-vis absorption spectroscopy and favorable proton conduction. Remarkably, after loading cytarabine (Ara-C) as a model drug molecule, these pH-responsive COFs showed an excellent and intelligent sustained-release effect. They showed an almost 4-fold increase in the Ara-C release at pH=4.8 than at pH=7.4, which will effectively improve drug-targeting and reduce drug side effects. Thus, these results open a way toward designing 3D stimuli-responsive functionalized COF materials and promote their potential applications as carriers in the field of disease treatment.

Mots clés: covalent organic frameworks; functionalization; stimuli-responsive; drug release

Domaines: Chimie

Wenjuan Zhao, Chengyang Yu, Jie Zhao, Fengqian Chen, Xinyu Guan, et al.. Three-Dimensional Hydrazone-Equipped Covalent Organic Frameworks as pH-Triggered Rotary Switches. Small, 2021, 17 (41), pp.2102630. ⟨10.1002/smll.202102630⟩. ⟨hal-03424360⟩