A label-free reusable aptasensor for Alzheimer's disease

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Analytical Chemistry

Background:

• Early detection of amyloid-beta (Aβ) oligomers is crucial for diagnosing neurodegenerative diseases like Alzheimer's.
• Existing detection methods often lack sensitivity, reusability, or are label-dependent.
• Development of sensitive, selective, and reusable biosensors is essential for clinical diagnostics.

Purpose of the Study:

• To design and develop a label-free, reusable aptasensor for the early and effective detection of amyloid-beta (Aβ) oligomers.
• To utilize a luminescent nanoscale lanthanum-based metal-organic framework (L-MOF) as signal tags and aptamer-functionalized magnetic beads (Apt-MB) as capture probes.
• To achieve sensitive and selective detection of Aβ oligomers in biological samples like serum.

Main Methods:

• A novel aptasensor architecture combining L-MOF-armored anti-DNA antibodies as signal tags and Apt-MB as capture probes.
• Utilizing antigen-antibody interactions for signal generation and Aβ oligomer capture.
• Employing fluorescence quenching and recovery mechanisms for signal readout and aptasensor reusability via heat treatment.

Main Results:

• The aptasensor demonstrated high sensitivity and selectivity for Aβ oligomers with a limit of detection (LOD) of 0.4 pg/mL.
• An excellent linear detection range from 0.001 to 100 ng/mL was achieved.
• The aptasensor proved to be reusable after heat-induced aptamer recovery, maintaining detection performance.

Conclusions:

• The developed label-free reusable aptasensor offers a promising strategy for sensitive and selective Aβ oligomer detection.
• This approach represents a significant advancement in the development of reusable aptasensors.
• The strategy holds potential for novel applications in the clinical diagnosis of Aβ-related diseases.