Related Experiment Video
Updated: Oct 20, 2025

Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
3D Hydrazone-Functionalized Covalent Organic Frameworks as pH-Triggered Rotary Switches
Wenjuan Zhao1, Chengyang Yu1, Jie Zhao2
1State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun, 130012, P. R. China.
Researchers developed novel 3D functionalized covalent organic frameworks (COFs) that act as pH-triggered molecular switches for smart drug delivery. These hydrazone-decorated COFs demonstrate controlled release of cytarabine (Ara-C), improving drug targeting.
Area of Science:
- Materials Science
- Nanotechnology
- Chemical Engineering
Background:
- 3D functionalized covalent organic frameworks (COFs) are crucial for advanced applications.
- Developing stimuli-responsive COFs is key for targeted therapies.
- Hydrazone groups offer potential for molecular switching functionalities.
Purpose of the Study:
- To report the first 3D hydrazone-decorated COFs functioning as pH-triggered molecular switches.
- To explore their application in stimuli-responsive drug delivery systems.
- To investigate the controlled release of cytarabine (Ara-C) using these COFs.
Main Methods:
- Utilized a multi-component bottom-up synthesis strategy to create 3D functionalized COFs.
- Incorporated hydrazone groups onto the channel walls of the COFs.
- Investigated pH-triggered E/Z isomerization using UV-vis spectroscopy and proton conduction.
- Loaded cytarabine (Ara-C) into the COFs for drug delivery studies.
Main Results:
- Successfully synthesized 3D hydrazone-decorated COFs with reversible pH-triggered E/Z isomerization.
- Demonstrated pH-dependent proton conduction properties.
- Achieved an intelligent sustained-release effect for cytarabine (Ara-C).
- Observed a significant increase in Ara-C release at acidic pH (4.8) compared to neutral pH (7.4).
Conclusions:
- These novel 3D functionalized COFs act as effective pH-triggered molecular switches.
- The developed COFs show great potential as intelligent drug carriers for targeted disease treatment.
- This work paves the way for designing advanced stimuli-responsive COF materials.
More Related Videos
06:24High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
Published on: October 31, 2019
08:42Microfluidic-based Synthesis of Covalent Organic Frameworks COFs: A Tool for Continuous Production of COF Fibers and Direct Printing on a Surface
Published on: July 10, 2017
Related Concept Videos
ortho–para-Directing Deactivators: Halogens
Diazonium Group Substitution with Halogens and Cyanide: Sandmeyer and Schiemann Reactions
ortho–para-Directing Activators: –CH3, –OH, –⁠NH2, –OCH3
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Woodward–Hoffmann Selection Rules and Microscopic Reversibility
[4+2] Cycloaddition of Conjugated Dienes: Diels–Alder Reaction