Facile Dissolution of Zein Using a Common Solvent Dimethyl Sulfoxide

Area of Science:

• Materials Science
• Polymer Chemistry
• Biomaterials

Background:

• Zein protein conformation and stability are crucial for material properties.
• Traditional zein solvents like aqueous ethanol and acetic acid have limitations.

Purpose of the Study:

• To investigate dimethyl sulfoxide (DMSO) as a novel solvent for zein.
• To characterize zein solutions and films prepared using DMSO.
• To evaluate the mechanical properties of DMSO-derived zein films.

Main Methods:

• Zein dissolution in DMSO.
• Rheological analysis to determine solvent quality (Huggins coefficient).
• Small-angle X-ray scattering (SAXS) for conformational analysis.
• Thermogravimetric analysis (TGA) for residual solvent quantification.
• Mechanical testing of fabricated zein films.

Main Results:

• DMSO readily dissolved zein, forming stable solutions for over two weeks.
• Rheological analysis indicated DMSO as a good solvent for zein (Huggins coefficient = 0.24).
• SAXS revealed an elongated zein conformation (2.8 nm × 2.8 nm × 14.8 nm) in DMSO.
• Zein films exhibited high mechanical strength (320.6% strain, 1.9 MPa stress) with 15 wt% residual DMSO.
• Thermogravimetric analysis confirmed residual DMSO content.

Conclusions:

• Dimethyl sulfoxide (DMSO) is an effective solvent for zein processing.
• DMSO facilitates the fabrication of robust zein-based materials with superior mechanical performance.
• DMSO offers a promising alternative solvent for expanding the practical applications of zein.