Amperometric Biosensor for Quantitative Measurement Using Sandwich Immunoassays

Area of Science:

• Biosensing and electrochemical detection
• Biomarker analysis for diagnostics
• Point-of-Care (PoC) technologies

Background:

• Current clinical immunoassay methods require specialized equipment, limiting Point-of-Care (PoC) applications.
• Electrochemical biosensors offer a portable, cost-efficient alternative for analyzing biomarkers in biological fluids.
• Optimizing sensing surfaces, immobilization, and reporter systems is crucial for enhanced biosensor performance.

Purpose of the Study:

• To develop and validate a robust electrochemical immunosensor for biomarker detection.
• To adapt enzyme-linked immunosorbent assay (ELISA) for electrochemical sensing platforms.
• To evaluate the sensor's performance for detecting Neutrophil Gelatinase-Associated Lipocalin (NGAL) in urine.

Main Methods:

• Surface characterization of screen-printed and thin-film electrodes using SEM and AFM.
• Adaptation of ELISA for an electrochemical sensor format.
• Detection of NGAL in urine to assess sensor robustness and reproducibility.

Main Results:

• The developed electrochemical immunosensor demonstrated a low detection limit of 1 ng/mL for NGAL.
• A linear detection range of 3.5-80 ng/mL was achieved with a coefficient of variation (CV%) of 8%.
• The platform technology proved suitable for immunoassay-based sensors on various electrode types.

Conclusions:

• The developed electrochemical immunosensor is a viable technology for PoC biomarker detection.
• The sensor offers a robust, reproducible, and sensitive method for NGAL quantification in urine.
• This platform technology is adaptable for developing various immunoassay-based electrochemical sensors.