Self-Assembled Homopolymeric Spherulites from Small Molecules in Solution

Area of Science:

• Materials Science
• Polymer Chemistry
• Supramolecular Chemistry

Background:

• Polymeric spherulites typically form via melt crystallization, with solution-based growth being uncommon.
• Complex polymers and dilute solutions are usually required for solution-based spherulite formation.

Purpose of the Study:

• To report a novel, mild method for forming luminescent spherulites at room temperature.
• To explore the self-assembly and properties of spherulites derived from a simple molecule, benzene-1,4-dithiol (BDT).

Main Methods:

• Benzene-1,4-dithiol (BDT) was polymerized into oligomers (PBDT) via disulfide bonds in aqueous buffer.
• PBDT nanoparticles were dissolved in dimethylformamide and underwent chain elongation to form spherulites (rPBDT) within 10 minutes.
• Spherulite geometry was controlled by adjusting PBDT concentration and reaction time.

Main Results:

• Uniform, luminescent spherulites were successfully formed at room temperature.
• The resulting spherulites (rPBDT) demonstrated robust structures and clusterization-triggered emission.
• Biocompatibility and efficient cellular uptake were observed, indicating potential as traceable drug carriers.

Conclusions:

• A new pathway for creating versatile superstructures from small molecules was established.
• The developed system facilitates hierarchical assembly relevant to complex biological systems.
• The luminescent spherulites show promise for applications in drug delivery and bio-imaging.