Bioinspired Threonine-Based Polymers with Potent Ice Recrystallization Inhibition Activity

Area of Science:

• Materials Science
• Biochemistry
• Polymer Chemistry

Background:

• Ice growth poses challenges across industries.
• Natural ice-binding proteins (IBPs) inhibit ice recrystallization (IRI) but are costly and unstable.
• Bioinspired polymers are explored as alternatives to IBPs.

Purpose of the Study:

• To develop a synthetic polymer with potent ice recrystallization inhibition (IRI) activity.
• To mimic the ice-binding behavior of natural ice-binding proteins (IBPs).
• To inform the synthesis of a robust bioinspired polymer for ice growth mitigation.

Main Methods:

• Studied IRI activity of threonine polypeptide (pThr) in phosphate-buffered saline (PBS).
• Synthesized and characterized poly(2-hydroxypropyl methacrylamide) (pHPMA) using pThr as a molecular model.
• Evaluated pHPMA's IRI activity across different molecular weights and concentrations.

Main Results:

• Threonine polypeptide (pThr) showed significant IRI activity in PBS.
• Poly(2-hydroxypropyl methacrylamide) (pHPMA) demonstrated potent IRI activity at ultralow concentrations (0.01 mg/mL) in neutral PBS.
• pHPMA's IRI activity was effective at low molecular weights (2.3 kDa) and improved with higher molecular weights (32.8 kDa).

Conclusions:

• pHPMA is a robust bioinspired polymer that effectively mitigates ice crystal growth.
• pHPMA exhibits IRI activity comparable to native IBPs at similar concentrations.
• The developed polymer offers a promising, stable alternative for ice growth mitigation.