Surface Biochemical Modification of Poly(dimethylsiloxane) for Specific Immune Cytokine Response

Area of Science:

• Biomaterials Science
• Biosensor Technology
• Immunology

Background:

• Proinflammatory cytokines, like tumor necrosis factor α (TNF-α), are implicated in various inflammatory diseases including COVID-19, sepsis, and cancer.
• Non-invasive biosensors for continuous monitoring of TNF-α in biological fluids, such as sweat, are needed for early disease detection and management.
• Polydimethylsiloxane (PDMS)-based platforms offer potential for developing such advanced biosensing devices.

Purpose of the Study:

• To develop and optimize a biofunctionalization process for PDMS surfaces for the creation of a human TNF-α biosensor.
• To establish reliable methods for characterizing the biofunctionalized PDMS surface.
• To demonstrate the efficacy of the developed biosensor in detecting and quantifying human TNF-α.

Main Methods:

• PDMS surfaces were biofunctionalized using a silanization reaction with 3-aminopropyltriethoxysilane.
• Surface characterization involved water contact angle measurements, electron dispersive X-ray, and Fourier transform infrared spectroscopy.
• An ELISA-type immunoassay with fluorescent microscopy was employed for TNF-α detection and quantification.

Main Results:

• Optimal silanization conditions were identified, ensuring a stable and reproducible aminosilane layer on PDMS surfaces.
• The developed biosensor successfully detected and quantified human TNF-α.
• A limit of detection of 0.55 μg/mL (31.6 nM) for TNF-α was achieved.

Conclusions:

• A novel, rapid, stable, and simple biofunctionalization method for PDMS-based TNF-α biosensors was successfully developed.
• This PDMS-based biosensor represents a promising non-invasive tool for monitoring TNF-α levels in biological fluids.
• The findings pave the way for continuous monitoring of inflammatory conditions through advanced biosensor technology.