Surface modification of silicon and gold-patterned silicon surfaces for improved biocompatibility and cell patterning...

Area of Science:

• Biomaterials Science
• Surface Chemistry
• BioMEMS Technology

Background:

• Silicon-based microelectromechanical systems (BioMEMS) require biocompatible surfaces.
• Controlling protein adsorption and cell attachment is crucial for biosensor functionality.
• Existing surface modification techniques may not offer sufficient selectivity.

Purpose of the Study:

• To develop and evaluate methoxy-polyethylene glycol (M-PEG silane) coatings for silicon and gold-patterned silicon substrates.
• To assess the efficacy of M-PEG silane in resisting plasma protein adsorption.
• To investigate selective cell patterning on modified surfaces and understand the influence of gold electrodes.

Main Methods:

• Self-assembly technique used to modify clean silicon and gold-patterned silicon platforms with M-PEG silane.
• Fibrinogen and immunoglobulin G (IgG) employed as model plasma proteins to quantify protein adsorption.
• Macrophage and fibroblast cells utilized to evaluate cell patterning selectivity and tissue compatibility.

Main Results:

• M-PEG silane modification significantly enhanced protein resistance on silicon surfaces.
• PEGylated gold-patterned silicon surfaces demonstrated near-complete elimination of protein adsorption and cell attachment on silicon regions.
• Selective cell patterning was observed on the gold regions of the PEG-modified gold-patterned silicon substrate.

Conclusions:

• M-PEG silane coatings offer a promising strategy for creating biocompatible surfaces for silicon-based BioMEMS.
• This approach effectively prevents non-specific protein and cell adhesion on silicon, enabling selective patterning.
• The developed surfaces are particularly suitable for biosensor applications requiring a metal-insulator format.