Synthesis and cellular compatibility of multi-block biodegradable poly(ε-caprolactone)-based polyurethanes.

Area of Science:

• Polymer Chemistry
• Materials Science
• Biomaterials

Background:

• Block copolymers are versatile materials with tunable properties.
• Controlling copolymer structure is key to optimizing performance for specific applications.

Purpose of the Study:

• To synthesize and characterize a library of poly(ε-caprolactone) (PCL)-based block copolymers.
• To investigate the influence of soft segment molecular weight and diisocyanate type on copolymer properties.
• To evaluate the degradation behavior and cellular compatibility of the synthesized copolymers.

Main Methods:

• Synthesis of block copolymers by reacting PCL-diols of varying molecular weights with different diisocyanates and chain extenders.
• Thermal analysis (DSC, TGA) and X-ray diffraction (XRD) to determine copolymer structure and crystallinity.
• In vitro hydrolytic degradation studies.
• In vitro cell culture assays using a microarray format to assess cellular attachment and growth.

Main Results:

• Copolymer crystallinity was dependent on PCL-diol molecular weight and diisocyanate choice.
• Lower molecular weight PCL-diol (850 g/mol) with 1,4-phenylene diisocyanate (PDI) yielded crystalline copolymers, while other diisocyanates resulted in amorphous structures.
• Amorphous copolymers exhibited faster hydrolytic degradation rates compared to semi-crystalline ones.
• All 57 synthesized copolymers demonstrated excellent cellular compatibility, supporting cell attachment and proliferation.

Conclusions:

• The molecular weight of the PCL-diol soft segment and the type of diisocyanate significantly influence the crystalline structure and degradation profiles of the resulting block copolymers.
• The synthesized block copolymers, regardless of their crystallinity or degradation rate, are biocompatible and support cell growth, highlighting their potential as biomaterials.