Photopolymerizable and injectable polyurethanes for biomedical applications: synthesis and biocompatibility

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Injectable biomaterials are crucial for minimally invasive medical procedures.
• Photopolymerizable materials offer advantages in controlled in-situ fabrication.
• Developing cytocompatible and mechanically suitable polymers is essential for tissue engineering and regenerative medicine.

Purpose of the Study:

• To synthesize and characterize photopolymerizable and injectable polyurethane acrylates (PUAs).
• To evaluate the suitability of these PUAs for biomedical applications, focusing on injectability, mechanical properties, and cytocompatibility.
• To assess the in vitro and in vivo performance of the synthesized PUAs.

Main Methods:

• Synthesis of two types of PUAs using poly(propylene glycol) or poly(caprolactone diol) and hydroxyethyl methacrylate.
• Characterization using Fourier transform infrared spectroscopy (FTIR) for structural analysis.
• Evaluation of injectability, mechanical properties, and in vitro/in vivo cytocompatibility using mesenchymal stem cells and histology.

Main Results:

• Synthesized PUAs demonstrated suitable viscosity for injection and photopolymerization with visible light.
• Cured polymers exhibited mechanical properties comparable to soft tissues like skin.
• In vitro assays (MTT, collagen synthesis, alkaline phosphatase) and in vivo studies confirmed the cytocompatibility and low toxicity of the PUAs.
• Histology revealed no significant inflammatory response.

Conclusions:

• The synthesized photocurable PUAs are cytocompatible and possess favorable mechanical properties for biomedical applications.
• These injectable polymer systems support minimally invasive procedures and allow for in situ molding before visible light photopolymerization.
• The study highlights the potential of these PUAs as versatile biomaterials for various medical interventions.