Gas Cluster Ion Beam-Assisted Deposition for Fabricating Dry Multilayers Containing Enzyme and Substrate with...

Area of Science:

• Biomaterials Science
• Surface Science
• Protein Engineering

Background:

• Proteins often lack long-term stability in aqueous solutions.
• Dry storage of proteins is desirable for sample conservation.
• Fabricating functional multilayered protein structures requires precise deposition techniques.

Purpose of the Study:

• To investigate the efficacy of gas cluster ion beam (GCIB)-assisted deposition for creating stable, multilayered protein structures.
• To assess the impact of deposition parameters on protein activity and integrity.
• To demonstrate the creation of functional, dry-state enzymatic materials.

Main Methods:

• Gas cluster ion beam (GCIB)-assisted deposition using Ar$_{3000-5000}$$^+$ clusters.
• Sequential deposition of peptides, lysozyme, trypsin, glucose oxidase (GOx), and horseradish peroxidase.
• Analysis of protein activity via bioassays and integrity via SDS-PAGE.
• Fabrication of a dry trilayer enzymatic material.

Main Results:

• Successful fabrication of stable, well-separated peptide multilayers.
• Protein activity after deposition is linearly proportional to argon ion dose.
• Increased energy per atom (E/n) negatively affects lysozyme activity.
• Intact detection of proteins up to 80 kDa (GOx) using SDS-PAGE and bioassays.
• Demonstrated on-demand enzymatic reaction in a dry trilayer material.

Conclusions:

• GCIB-assisted deposition is a versatile technique for building stable, multilayered protein structures under vacuum.
• Protein activity can be preserved and modulated by controlling deposition parameters like ion dose and energy.
• This method facilitates the creation of functional dry-state protein-based materials for various applications.