System-on-fluidics immunoassay device integrating wireless radio-frequency-identification sensor chips.

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunosensors

Background:

• Point-of-care-test (POCT) devices require high sensitivity and precision for accurate diagnostics.
• Chemiluminescence (CL) immunoassays offer sensitive detection but can be affected by environmental factors like temperature.
• Existing POCT devices often lack robust temperature compensation, impacting signal stability and reliability.

Purpose of the Study:

• To develop a simple and sensitive POCT device for CL immunoassay.
• To implement a novel two-stage temperature compensation scheme for enhanced precision.
• To evaluate the device's performance for thyroid-stimulating hormone (TSH) detection.

Main Methods:

• A POCT device integrating a flow-channel reactor with photo-sensor and temperature-sensor chips was designed.
• Radio-frequency-identification (RFID) technology enabled batteryless, wireless data communication.
• A two-stage temperature compensation strategy was employed, differentiating photodiode signals and utilizing temperature sensor data.

Main Results:

• The two-stage temperature compensation significantly reduced dark-level fluctuation from 0.24 to 0.02 pA/°C.
• The optimized CL immunoassay for TSH achieved a low detection limit of 0.08 ng/ml (0.4 μIU/ml).
• The developed POCT device demonstrated reliable and sensitive performance.

Conclusions:

• The novel POCT device offers a simple, sensitive, and precise platform for CL immunoassays.
• The integrated temperature compensation system effectively mitigates environmental variations, enhancing diagnostic accuracy.
• This technology holds promise for improved point-of-care diagnostics, particularly for hormone level monitoring.