Biocompatible sensors for ammonia gas detection

Area of Science:

• Food Science
• Analytical Chemistry
• Biotechnology

Background:

• Ammonia gas is a byproduct of microbial degradation, signaling food deterioration.
• A reliable food freshness indicator is crucial for the food industry and consumer safety.
• Existing methods for ammonia detection may be complex or unsuitable for direct food contact.

Purpose of the Study:

• To develop and evaluate biocompatible sensors for detecting gaseous ammonia.
• To assess the efficacy of natural pigments (curcumin, anthocyanin) and bromothymol blue as ammonia sensors.
• To determine sensor performance under high humidity conditions relevant to packaged food.

Main Methods:

• Preparation and testing of three distinct dye-based sensors: curcumin, anthocyanin, and bromothymol blue.
• Evaluation of sensor composition, deposition materials, stability, and reversibility.
• Utilizing colorimetry (HSV color space H coordinate) with camera-based detection under simulated high-humidity conditions.

Main Results:

• All tested sensors demonstrated sensitivity to ammonia gas.
• The natural pigment-based sensors were found to be biocompatible and suitable for food contact.
• Performance was assessed under challenging high-humidity conditions, simulating real-world food packaging.

Conclusions:

• The developed dye-based sensors show potential as effective, low-cost food freshness indicators.
• Biocompatibility and stability under humidity make these sensors viable for the food industry.
• The colorimetric approach offers a simple, instrumentation-free method for ammonia detection.