Dip-pen nanolithography on SiOx and tissue-derived substrates: comparison with multiple biological inks

Area of Science:

• Biomaterials Science
• Nanolithography
• Tissue Engineering

Background:

• Micro and nanoscale manipulation of substrates is crucial for understanding cell behavior.
• Tissue-derived substrates offer unique biological relevance for cell-substrate interaction studies.
• Bruch's membrane (BM) presents a complex biological substrate for advanced patterning.

Purpose of the Study:

• To investigate the feasibility of dip-pen nanolithography for patterning biomolecules on tissue-derived substrates.
• To functionalize the Bruch's membrane (BM) with peptides and extracellular matrix (ECM) proteins.
• To enhance control over cell morphology and cell-substrate interactions on biological surfaces.

Main Methods:

• Dip-pen nanolithography was employed to pattern collagen-binding peptides and ECM proteins (laminin, fibronectin).
• Bruch's membrane (BM) was used as a tissue-derived substrate, with SiO(x) as a control.
• Triton X-100 was utilized for cleaning the BM, enhancing collagen exposure and surface hydrophilicity.

Main Results:

• Successful patterning of peptides and ECM proteins onto the inner collagenous zone of the BM.
• Triton X-100 cleaning resulted in a more hydrophilic BM surface (contact angle 67° ± 8.49°) while maintaining surface roughness (80 nm ± 18 nm) and collagen exposure.
• The modified BM surface allowed for patterning under lower humidity conditions.

Conclusions:

• Dip-pen nanolithography is a viable technique for patterning biomolecules on complex tissue-derived substrates like Bruch's membrane.
• The optimized cleaning protocol enhances substrate properties for nanolithographic applications.
• This approach facilitates the development of advanced biomaterials for studying cell-matrix interactions.