Ultra-sensitive detection of IgE using biofunctionalized nanoparticle-enhanced SPR

Area of Science:

• Biotechnology
• Nanotechnology
• Analytical Chemistry

Background:

• Allergic diseases are a significant health concern.
• Accurate and sensitive detection of immunoglobulin E (IgE) is crucial for diagnosing allergies.
• Existing detection methods may lack the required sensitivity or speed.

Purpose of the Study:

• To develop an ultra-sensitive surface-based detection method for IgE proteins.
• To enhance detection sensitivity using nanoparticle-enhanced surface plasmon resonance (SPR).
• To evaluate the potential of this method for allergic disease diagnosis.

Main Methods:

• Investigated anti-IgE and IgE-specific aptamers for IgE interaction using SPR.
• Measured Langmuir adsorption coefficients for probe-IgE interactions.
• Developed two sandwich assay strategies using biofunctionalized gold nanoparticles (Au-NPs) to amplify SPR signals.
• Compared detection performance of the two sandwich assay configurations.

Main Results:

• SPR detection limit for simple IgE adsorption was approximately 1 nM.
• Both nanoparticle-enhanced sandwich assay strategies achieved femtomolar detection limits for IgE.
• Anti-IgE and IgE-specific aptamers showed comparable binding affinities for IgE.

Conclusions:

• Nanoparticle-enhanced SPR offers a highly sensitive platform for IgE detection.
• The developed method demonstrates potential for sensitive and specific diagnosis of allergic diseases.
• This approach significantly improves upon traditional SPR detection limits for IgE.