Layer-by-layer films based on catechol-modified polysaccharides produced by dip- and spin-coating onto different...

Area of Science:

• Materials Science
• Biomaterials Engineering
• Surface Chemistry

Background:

• Developing advanced coatings for biomedical applications is crucial.
• Chitosan and hyaluronic acid are biocompatible natural polymers with potential for surface modification.
• Improving coating adhesion and bioactivity is a key challenge.

Purpose of the Study:

• To create and characterize layer-by-layer (LbL) films using catechol-modified chitosan and hyaluronic acid.
• To investigate the influence of dip-coating versus spin-coating techniques on film properties.
• To evaluate the effect of substrate surface roughness on coating morphology and wettability.

Main Methods:

• Layer-by-layer assembly of catechol-modified chitosan and hyaluronic acid.
• Dip-coating and spin-coating techniques applied to glass, stainless steel, and titanium substrates.
• Characterization using UV-Vis spectroscopy, FTIR imaging, SEM, AFM, and water contact angle measurements.

Main Results:

• Successful synthesis of modified polymers confirmed by UV-Vis.
• FTIR imaging provided novel insights into layer interdiffusion.
• Spin-coated films on glass exhibited superior smoothness and homogeneity with less interdiffusion compared to dip-coated films.
• Substrate surface roughness significantly impacted coating morphology and wettability for both methods.

Conclusions:

• Catechol modification enhances adhesive properties of chitosan and hyaluronic acid coatings.
• Spin-coating offers advantages in achieving smoother, more uniform LbL films, particularly on glass.
• Substrate characteristics play a critical role in determining the final properties of LbL coatings, necessitating tailored approaches for different materials.