Smart polymers driven by multiple and tunable hydrogen bonds for intact phosphoprotein enrichment

Area of Science:

• Biochemistry
• Materials Science
• Analytical Chemistry

Background:

• Phosphoprotein separation is crucial for understanding biological processes and diseases.
• Current methods using transition metal receptors or antibodies have limitations in sensitivity, recovery, and coverage.

Purpose of the Study:

• To synthesize and evaluate a novel smart copolymer material for enhanced phosphoprotein enrichment.
• To investigate the adsorption mechanism and tunable properties of the new material.

Main Methods:

• Synthesis of a smart copolymer material by modifying porous silica gel with poly[(N-isopropylacrylamide-co-4-(3-acryloylthioureido)benzoic acid)0.35] (NIPAAm-co-ATBA0.35@SiO2).
• Utilizing hydrogen bond complexation between ATBA monomers and phosphate groups for adsorption.
• Employing dispersive solid-phase extraction (dSPE) mode for selective phosphoprotein enrichment.

Main Results:

• The NIPAAm-co-ATBA0.35@SiO2 material demonstrated remarkable adsorption of α-casein, a model phosphoprotein.
• Adsorption was driven by hydrogen bonds and showed significant changes in surface viscoelasticity and roughness.
• Selective phosphoprotein enrichment was achieved, dependent on the carrier solvent's polarity.

Conclusions:

• The novel smart copolymer material offers a promising approach for selective phosphoprotein enrichment.
• This material has potential applications in facilitating top-down phosphoproteomics studies.
• The tunable adsorption properties highlight the utility of smart polymeric materials in biomolecule separation.