Interactions among proteins and hydrophobically modified polyelectrolytes

Area of Science:

• Polymer Chemistry
• Biomaterials Science
• Drug Delivery

Background:

• Hydrophobically modified polyelectrolytes offer unique properties for advanced applications.
• Pluronic block copolymers are widely used in biomedical fields.
• Protein stabilization and controlled release are critical in pharmaceutical development.

Purpose of the Study:

• To synthesize and characterize Pluronic-PAA copolymers.
• To investigate the gelation properties of Pluronic-PAA solutions at body temperature.
• To evaluate the potential of Pluronic-PAA gels for protein stabilization and protection against degradation.

Main Methods:

• Synthesis of poly(acrylic acid) conjugated with Pluronic F127 NF surfactant.
• Rheological measurements to assess gelation behavior.
• Circular dichroism spectroscopy to study protein tertiary structures.
• Shaking tests to evaluate protein aggregation.
• Enzymatic degradation assays using alpha-chymotrypsin and trypsin.

Main Results:

• Pluronic-PAA copolymer solutions formed gels at low concentrations and body temperature.
• Gelled solutions demonstrated enhanced retention properties.
• Tertiary structures of human insulin, hemoglobin, and albumin were stabilized.
• Insulin aggregation was impeded in Pluronic-PAA gels.
• Pluronic-PAA significantly hindered insulin degradation by alpha-chymotrypsin (7-fold).
• Pluronic-PAA inhibited trypsin activity by extracting calcium ions, preventing protein degradation.

Conclusions:

• Pluronic-PAA copolymers form thermoreversible gels with potential for topical applications.
• These gels effectively stabilize protein structures and prevent aggregation.
• Pluronic-PAA acts as a protective agent against enzymatic degradation of proteins, offering a novel approach for protein stabilization.