Reusable chromium-coated quartz crystal microbalance for immunosensing

Area of Science:

• Materials Science
• Biotechnology
• Analytical Chemistry

Background:

• Development of robust and reusable platforms is crucial for efficient immunosensor technology.
• Quartz crystal microbalances (QCMs) are sensitive devices for monitoring mass changes, ideal for biosensing applications.
• Chromium films offer a stable substrate for surface modification and biomolecule immobilization.

Purpose of the Study:

• To investigate the utility of oxidized chromium films on QCMs as a reusable platform for immunosensor development.
• To explore the covalent immobilization of immunoglobulins (IgG) onto chromium surfaces using silane chemistry.
• To analyze the binding interactions between rabbit IgG and goat anti-rabbit IgG on functionalized chromium surfaces.

Main Methods:

• Deposition of chromium films onto quartz crystal microbalances.
• Surface functionalization of chromium films using silane chemistry for covalent antibody grafting.
• Immobilization of rabbit IgG and goat anti-rabbit IgG on modified chromium surfaces.
• Investigation of binding affinity using QCM measurements.
• Regeneration of the chromium surface using piranha etch for reusability.

Main Results:

• Successful covalent immobilization of rabbit IgG and goat anti-rabbit IgG on silane-modified chromium surfaces.
• Demonstration of specific binding interactions between the immobilized antibodies and their targets.
• Oxidized chromium platform exhibited high repeatability and reusability after regeneration.
• Investigated differences in binding based on the orientation of immobilized antibodies.

Conclusions:

• Oxidized chromium is a promising reusable substrate for immunosensor fabrication.
• Silane chemistry provides an effective method for covalent antibody immobilization on chromium.
• The developed immunosensor platform shows potential for sensitive and repeatable detection of IgG.
• The reusability of the chromium platform reduces costs and enhances the efficiency of biosensing protocols.