Screening Molecular Recognition Element-Based SWCNT Optical Sensors for the Inflammatory Cytokine TNF-α.

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Immunology

Background:

• Tumor Necrosis Factor-alpha (TNF-α) is a key proinflammatory cytokine implicated in numerous diseases.
• Accurate quantification of TNF-α is vital for disease diagnosis and monitoring therapeutic responses.
• Single-walled carbon nanotubes (SWCNT) offer unique photoluminescent properties for biosensing applications.

Purpose of the Study:

• To evaluate aptamer- and antibody-based sensors for TNF-α detection using SWCNT signal transduction.
• To optimize sensor performance in complex biological matrices like serum.
• To identify a lead sensor construct for potential diagnostic and research applications.

Main Methods:

• Development and testing of multiple aptamer and antibody sensor constructs targeting TNF-α.
• Utilizing SWCNT near-infrared photoluminescence for signal transduction.
• Assessing sensor sensitivity and selectivity in serum, with and without passivation and quencher modifications.

Main Results:

• Several aptamer and antibody sensors demonstrated sensitive and selective TNF-α detection in serum within a physiological range.
• Sensor performance was enhanced by passivation and the incorporation of an exogenous quencher.
• An aptamer sequence modified with a Black Hole Quencher, combined with poly-L-Lysine passivation, achieved selective serum detection.

Conclusions:

• Translating molecular recognition elements to new platforms (SWCNT) and conditions (serum) presents challenges but is feasible.
• A lead sensor construct was validated, improving upon previously unsuccessful designs in serum.
• The developed sensors and assessment framework hold promise for diagnosing and studying inflammation-driven chronic diseases.