Multiplexed immunoassay using the stabilized enzymes in mesoporous silica

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• Enzyme immobilization is crucial for improving enzyme stability and activity in assays.
• Mesoporous silica offers a high surface area for efficient enzyme loading.
• Conventional immunoassays can face limitations in sensitivity and multiplexing capabilities.

Purpose of the Study:

• To develop a multiplexed immunoassay system using enzyme-immobilized mesoporous silica as nanoscale enzyme reactors (NERs).
• To enhance enzyme loading, activity, and stability for improved immunoassay performance.
• To demonstrate the capability of the developed system for sensitive and simultaneous detection of multiple antigens.

Main Methods:

• Construction of antibody-conjugated nanoscale enzyme reactors (NERs) by immobilizing glucose oxidase (GO) and trypsin (TR) into mesoporous silica.
• Development of a sandwich-type magnetic bead-based immunoassay (NER-LISA) utilizing the antibody-conjugated NERs.
• Simultaneous detection of human IgG and chicken IgG by measuring enzyme activities at different wavelengths.

Main Results:

• NER-LISA achieved a detection limit of 67 pM for human IgG, showing 20 times higher sensitivity than conventional ELISA.
• The system successfully performed simultaneous detection of two different IgG antigens.
• The NER approach effectively retained protease activity, preventing enzyme degradation during the assay.

Conclusions:

• NER-LISA offers a robust platform for highly sensitive and multiplexed immunoassays.
• The use of mesoporous silica as nanoscale enzyme reactors significantly improves enzyme performance and assay sensitivity.
• This technology holds promise for advanced diagnostic applications requiring simultaneous detection of multiple biomarkers.