Protein adsorption and endothelial cell attachment and proliferation on PAPI-based additive modified poly(ether...

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Cell Biology

Background:

• Poly(ether urethane urea) (PEUU) is a biomaterial with potential applications in vascular devices.
• Understanding surface interactions, including protein adsorption and cell behavior, is crucial for optimizing biomaterial performance.
• Modifications to PEUU, such as additive incorporation or polymer chain end-capping, can influence its biological interactions.

Purpose of the Study:

• To investigate the effects of poly(methylene-[polyphenyl isocyanate]) (PAPI) additives and end-capping moieties (diisopropylaminoethyl (DIPAA) and decyl (DA)) on PEUU material properties.
• To evaluate protein adsorption, endothelial cell attachment, and proliferation on modified PEUU formulations.
• To correlate surface properties, such as contact angle, with observed biological responses.

Main Methods:

• Preparation of PEUU formulations with PAPI additives and DA/DIPAA end-capping.
• Protein adsorption assays using various proteins.
• Endothelial cell attachment and proliferation assays.
• Contact angle measurements (advancing and receding) using the sessile drop method.

Main Results:

• PAPI-loaded PEUU formulations exhibited significantly lower protein adsorption compared to unloaded PEUU.
• PEUU films with PAPI-DA and polyethylene glycol-PAPI-DA showed enhanced endothelial cell attachment and proliferation, comparable to tissue culture polystyrene.
• PEUU films with PAPI-DIPAA and PEG-PAPI-DIPAA showed significantly reduced cell attachment and proliferation.
• DA and DIPAA end-capped PEUU films did not show consistent variations in protein adsorption or cell behavior compared to the base PEUU.
• Contact angle analysis indicated that PAPI additives migrated to the PEUU-water interface, while DA and DIPAA end-caps did not appear to be present at the hydrated surface.

Conclusions:

• PAPI additives incorporated into PEUU can favorably modify surface properties, leading to reduced protein adsorption and enhanced endothelial cell response.
• The specific nature of the additive (hydrophobic/amphiphilic) and its location at the surface significantly impacts biological interactions.
• End-capping with DA or DIPAA moieties did not substantially alter the surface properties or biological performance of PEUU in this study.
• Surface migration of additives during film formation is a key factor in determining the biological performance of modified PEUU biomaterials.