A portable luminometer with a disposable electrochemiluminescent biosensor for lactate determination

Area of Science:

• Analytical Chemistry
• Biosensors
• Electrochemistry

Background:

• Lactate determination is critical in clinical diagnostics and biochemical analysis.
• Existing methods for lactate measurement can be time-consuming or require complex instrumentation.
• Development of rapid, sensitive, and portable lactate detection systems is highly desirable.

Purpose of the Study:

• To describe a novel hand-held luminometer system for lactate determination.
• To present the design and performance of one-shot biosensors based on screen-printed electrodes for electrochemiluminescence (ECL) detection.
• To optimize the biosensor and luminometer for sensitive and reproducible lactate measurements.

Main Methods:

• Fabrication of one-shot biosensors using screen-printed electrodes with immobilized lactate oxidase and luminol.
• Development of a hand-held luminometer incorporating a silicon photodiode detector and a programmable potentiostat.
• Optimization of membrane composition and reaction conditions for enhanced sensitivity.
• Signal processing circuitry for low-level photocurrent acquisition and noise attenuation.

Main Results:

• The biosensor system demonstrated rapid response (2.5 min acquisition time).
• Linear lactate detection was achieved in the range of 8 × 10⁻⁶ to 2 × 10⁻⁴ M.
• A low detection limit of 2.4 × 10⁻⁶ M was obtained.
• Good sensor-to-sensor reproducibility (RSD of 7-10%) was observed.

Conclusions:

• The developed hand-held luminometer and one-shot biosensor system provide a sensitive, rapid, and reproducible platform for lactate determination.
• The system's portability and performance make it suitable for point-of-care or field applications.
• Further optimization could enhance sensitivity and expand the application range for this ECL-based lactate sensor.