SERS-Based Microfluidic Bioscreening Platform for Selective Detection of β-Amyloid Peptides.

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Nanotechnology

Background:

• Alzheimer's disease is associated with the accumulation of beta-amyloid peptide (Aβ₁-42).
• Early detection of Aβ₁-42 is crucial for diagnosis and treatment monitoring.
• Existing detection methods may lack the required sensitivity and selectivity.

Purpose of the Study:

• To develop a highly sensitive and selective microfluidic device for Aβ₁-42 detection.
• To utilize surface-enhanced Raman spectroscopy (SERS) with novel nanomaterials for enhanced detection.
• To create an effective screening platform for Aβ₁-42 in simulated cerebrospinal fluid.

Main Methods:

• Fabrication of a polydimethylsiloxane (PDMS) microfluidic device using photo- and soft lithography.
• Functionalization of silver nanoparticles (AgNPs) with a purine ligand (Pu) to create SERS hotspots.
• Integration of the Pu-AgNP SERS substrate within the microfluidic device and sealing via thermal cross-linking.

Main Results:

• The developed microfluidic device demonstrated high sensitivity and selectivity for Aβ₁-42 detection.
• The Pu-AgNP SERS substrate generated effective hotspots for signal amplification.
• The device provided almost noise-free measurements with excellent limit-of-detection values for Aβ₁-42.

Conclusions:

• The novel microfluidic SERS device offers a promising platform for sensitive and selective Aβ₁-42 detection.
• This technology has potential applications in early Alzheimer's disease diagnosis.
• The integration of nanomaterials and microfluidics enhances analytical performance for biomarker detection.