Mucin-chitosan complexes at the solid-liquid interface: multilayer formation and stability in surfactant solutions.

Area of Science:

• Surface science
• Biomaterials science
• Physical chemistry

Background:

• Mucin, a biologically significant glycoprotein, plays crucial roles in lubrication and protection.
• Understanding mucin adsorption and layer stability is vital for biomaterial applications.
• The interaction of adsorbed layers with surfactants requires investigation for controlled surface modification.

Purpose of the Study:

• To investigate mucin and mucin-chitosan complex layer formation on negatively charged surfaces.
• To evaluate the stability of these adsorption layers in the presence of an anionic surfactant, sodium dodecyl sulfate (SDS).
• To develop a method for protecting mucin layers from surfactant-induced desorption.

Main Methods:

• Ellipsometry and interferometric surface apparatus were used to study adsorption layer formation and thickness.
• Atomic force microscopy (AFM) provided high-resolution imaging of surface structures.
• Controlled exposure to varying concentrations of sodium dodecyl sulfate (SDS) assessed layer stability.

Main Results:

• Mucin adsorbed onto negatively charged silica and mica surfaces, forming highly hydrated layers.
• These mucin layers were susceptible to desorption by SDS at concentrations above 0.2 cmc.
• Mucin-chitosan complexes exhibited enhanced stability, resisting SDS desorption up to 1 cmc.
• The formation of mucin-chitosan multilayers was demonstrated.

Conclusions:

• Mucin adsorption layers are sensitive to anionic surfactants like SDS.
• Complexation with chitosan significantly enhances the stability of mucin layers against surfactant removal.
• This study presents a novel method for stabilizing mucin layers, with potential applications in biomaterials and surface coatings.