Highly sensitive/selective 3D nanostructured immunoparticle-based interface on a multichannel sensor array for...

Area of Science:

• Biomaterials Science
• Neuroscience
• Analytical Chemistry

Background:

• Accumulation of beta-amyloid (Aβ) peptides is a hallmark of Alzheimer's disease (AD).
• Developing ultrasensitive assays for Aβ detection, especially from blood, remains a significant challenge.
• Current diagnostic methods for AD have limitations in sensitivity and accessibility.

Purpose of the Study:

• To develop a novel, ultrasensitive electrochemical biosensor for simultaneous detection of Aβ42 and Aβ40 peptides in serum.
• To create an easily integrated Point-of-Care Testing (PoCT) device for early AD diagnosis.
• To compare the diagnostic efficacy of the developed biosensor with existing methods like microPET imaging and behavioral tests.

Main Methods:

• A one-step electrophoresis/electropolymerization strategy was employed to create a conductive silk fibroin-based immunoparticle (CSIP) hierarchical interface.
• Electropolymerized Poly(3,4-ethylenedioxythiophene) (PEDOT) was used to bridge CSIPs for enhanced conductivity and signal transduction.
• The developed multi-sensing electrochemical immunosensor array (MEIA) platform was tested for its ability to detect Aβ42 and Aβ40 in serum samples from AD animal models.

Main Results:

• The CSIP interface demonstrated excellent electrochemical properties, facilitating biomolecule interaction and redox catalysis.
• Ultrasensitive detection limits were achieved: 6.63 pg/mL for Aβ40 and 3.74 pg/mL for Aβ42.
• The MEIA platform provided more informative results for early-stage AD animals compared to microPET imaging and behavioral tests.

Conclusions:

• The developed silk fibroin-based electrochemical biosensor offers a promising tool for early Alzheimer's disease diagnosis via blood tests.
• This work expands the application of silk fibroin in advanced biomaterials and electrochemical sensing.
• The CSIP interface and MEIA platform hold potential for developing novel multichannel electrochemical immunosensor arrays for various disease biomarkers.