Azobenzene-Based Conjugated Polymers: Synthesis, Properties, and Biological Applications

Area of Science:

• Materials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Conjugated polymers (CPs) are functional materials with applications in optical and electronic devices due to their delocalized backbones and processable side groups.
• Incorporating azobenzene functionality into CPs imparts multistimuli responsiveness and fluorescence quenching properties.
• Significant advancements have been made in azobenzene-based conjugated polymers (azo-CPs) through diverse molecular designs and synthetic routes.

Purpose of the Study:

• To comprehensively review the research field of azo-CPs.
• To focus on structural characteristics, synthesis methods, and applications of general azo-CPs and charged azo-CPs (azo-CPEs).

Main Methods:

• Categorization of azo-CPs based on molecular structure: side-chain incorporation, main-chain integration, and branched structures.
• Review of diverse molecular design strategies and synthetic pathways for azo-CPs.
• Exploration of applications, particularly in charged azo-CPs (azo-CPEs).

Main Results:

• Azo-CPs can be classified into three main structural types: linear with side-chain azobenzene, linear with main-chain azobenzene, and branched azo-CPs.
• Azobenzene incorporation leads to stimuli-responsive and fluorescence-quenching behaviors.
• Charged azo-CPs (azo-CPEs) show potential for advanced applications.

Conclusions:

• Azo-CPs represent a rapidly evolving research area with versatile structural designs.
• These polymers are highly promising for biomedical applications, including biosensing, bioimaging, targeted protein degradation, and cellular apoptosis induction.