Thermoresponsive Poly(vinyl methyl ether) (PVME) Retained by 3-Aminopropyltriethoxysilane (APTES) Network

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomedical Engineering

Background:

• Thermoresponsive polymers (TRPs) are crucial for applications like membrane fouling control and cell sheet harvesting.
• Poly(vinyl methyl ether) (PVME) offers a cost-effective, easily processed alternative to poly(N-isopropylacrylamide) (pNIPAAm), with a transition near physiological temperatures (32-35 °C).

Purpose of the Study:

• Investigate processing conditions for stable poly(vinyl methyl ether) (PVME) thin films on silica surfaces.
• Evaluate the thermoresponsive behaviors (TRB) of these retained PVME films.
• Assess potential applications in low-fouling and cell harvesting.

Main Methods:

• PVME/3-aminopropyltriethoxysilane (APTES) blend thin films (90:10 and 50:50 ratios) were spin-coated and annealed at various temperatures (40-120 °C) and durations (1-3 days).
• Film retention was assessed after rinsing and soaking in water.
• Thermoresponsive behavior was evaluated using water contact angle measurements.
• Protein adsorption and particle attachment were measured at room temperature and 37 °C.
• Human mesenchymal stem cell adhesion and detachment were observed at different temperatures.

Main Results:

• Annealing at ≥40 °C was essential for PVME film retention on silica, with higher temperatures enhancing stability.
• All retained PVME films exhibited thermoresponsive behavior, confirmed by contact angle changes.
• PVME films reduced particle attachment and protein adsorption at room temperature compared to 37 °C, with greater effect in 90:10 blends.
• Human mesenchymal stem cells adhered and proliferated at 37 °C and detached readily at room temperature.

Conclusions:

• Stable, thermoresponsive PVME films can be prepared on silica surfaces using APTES entrapment and appropriate annealing.
• These PVME surfaces demonstrate potential for developing low-fouling materials.
• The thermoresponsive nature of PVME films facilitates noninvasive cell harvesting, particularly for stem cells.