Thermoresponsive anionic copolymer brush-grafted surfaces for cell separation.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Regenerative Medicine

Background:

• Cell separation without surface modification is critical for tissue engineering and regenerative medicine.
• Existing methods often require invasive cell treatments, limiting their applicability.

Purpose of the Study:

• To develop a novel thermoresponsive anionic polymer brush system for label-free cell separation.
• To evaluate the efficacy of this system in separating different cell types relevant to cardiovascular tissue engineering.

Main Methods:

• Synthesis of a thermoresponsive anionic polymer brush P(NIPAAm-co-tBAAm-co-AAc) using activator regenerated by electron transfer atom transfer radical polymerization (ARGET-ATRP).
• Modification of glass surfaces with the synthesized polymer brushes.
• Evaluation of surface properties including negative charge (zeta potential) and thermal responsiveness (phase transition temperature).
• Investigation of cell adhesion and detachment behavior of human umbilical vein endothelial cells (HUVEC) and human aortic smooth muscle cells (SMC).

Main Results:

• The polymer brush exhibited tunable phase transition temperatures between 37-20°C for controlled cell adhesion and detachment.
• HUVEC showed prompt detachment, while SMC displayed higher adhesion on the anionic polymer brush surfaces.
• A mixture of HUVEC and SMC was successfully separated by simply adjusting the temperature, leveraging differential adhesion properties.

Conclusions:

• The developed thermoresponsive anionic polymer brush-modified surface provides a promising tool for label-free cell separation.
• This technique is applicable to separating cell types in cardiovascular tissue engineering, offering a non-invasive approach.