Polysaccharide-based nano-engineered multilayers for controlled cellular adhesion in label-free biosensors.

Area of Science:

• Biomaterials Science
• Cell Biology
• Surface Chemistry

Background:

• Controlling cellular adhesion is crucial for biomaterial development and cell-based biosensing.
• Biocompatible layers are typically used to modulate cell adhesivity.

Purpose of the Study:

• To investigate the cellular adhesion properties of synthetic poly(diallyldimethylammonium chloride) (PDADMAC)/heparin and natural chitosan/heparin films.
• To correlate film properties with cell adhesion for biomaterial applications.

Main Methods:

• Fabrication and characterization of PDADMAC/heparin and chitosan/heparin multilayers.
• Physicochemical analysis using streaming potential measurements (SPM), quartz crystal microbalance (QCM-D), and optical waveguide lightmode spectroscopy (OWLS).
• Topographical imaging via atomic force microscopy (AFM) and cell adhesion evaluation using resonant waveguide grating (RWG) biosensors and digital holographic microscopy.

Main Results:

• PDADMAC/heparin films demonstrated significantly higher cellular adhesion of MC3T3-E1 preosteoblastic cells.
• Chitosan/heparin films exhibited negligible cell attachment.
• Efficient cell adhesion correlated with homogeneous and rigid multilayer structures (PDADMAC/heparin).
• Less effective adhesion was observed on "sponge-like" chitosan/heparin structures.

Conclusions:

• Polysaccharide-based multilayers offer versatile platforms for medical applications by enabling tunable control over cell adhesion.
• PDADMAC/heparin films are suitable for applications requiring enhanced cell adhesion, while chitosan/heparin films can be used to reduce it.
• The findings are relevant for both fundamental modeling and applied research in biomaterials and biosensing.