Development of Sequence-Controlled, Degradable, and Cytocompatible Oligomers with Explicit Fragmentation Pathways

Area of Science:

• Polymer Chemistry
• Materials Science
• Biomaterials

Background:

• Sequence-defined polymers mimic biopolymers like peptides and DNA.
• Understanding polymer degradation and products is crucial for applications.
• Limited research exists on the degradation of well-structured, sequence-defined polymers.

Purpose of the Study:

• To synthesize degradable pentamers using specific single unit monomer insertion (SUMI) techniques.
• To investigate the degradation mechanisms and products of these novel polymers.
• To evaluate the precise structures, cytotoxicity, and potential biomedical applications of the synthesized polymers and their degradation products.

Main Methods:

• Alternating photo-reversible addition-fragmentation chain-transfer (photo-RAFT) SUMI with N-substituted maleimides.
• Thermal radical ring-opening SUMI with 5,6-benzo-2-methylene-1,3-dioxepane (BMDO).
• High-resolution mass spectrometry (HRMS) and liquid chromatography-mass spectrometry (LC-MS) for degradation analysis.

Main Results:

• Two degradable pentamers were synthesized, featuring ester bonds formed from the BMDO monomer's exo-methylene group.
• The degradation pathways of the pentamers were elucidated for the first time using advanced mass spectrometry techniques.
• Precise structures and cytotoxicity data for both the SUMI products and their degraded compounds were obtained.

Conclusions:

• The study successfully produced sequence-defined, degradable polymers with potential for mimicking biopolymers.
• Novel insights into polymer degradation mechanisms were achieved through integrated analytical methods.
• The findings provide a credible foundation for the future development of these polymers in biomedical applications.