MoS₂-Based NH₃ Sensor for In Situ Helicobacter pylori Detection

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Early detection of Helicobacter pylori is vital for gastric cancer prevention.
• Current methods for H. pylori detection face challenges due to low ammonia concentrations.
• Noninvasive monitoring of H. pylori requires sensitive detection of metabolized ammonia (NH3).

Purpose of the Study:

• To develop a highly sensitive NH3 sensor for real-time H. pylori monitoring.
• To utilize molybdenum disulfide (MoS2) with metal nanoparticle decoration for enhanced sensor performance.
• To establish a noninvasive method for tracking H. pylori growth dynamics.

Main Methods:

• Fabrication of MoS2-based NH3 sensor decorated with iron nanoparticles.
• Characterization of sensor response to NH3 at varying concentrations and temperatures.
• Long-term stability testing of the sensor.
• Application of the sensor for real-time, in situ monitoring of H. pylori growth over 92 hours.

Main Results:

• The Fe-decorated MoS2 sensor exhibited a high response (40.9%) to 5.7 ppm NH3 at 25°C.
• Achieved a low limit of detection (LOD) of 6.2 ppb for NH3.
• Demonstrated excellent long-term stability, with a 12.5% response to 5.7 ppm NH3 after 5 months.
• Successfully monitored the NH3 release curve during H. pylori's exponential growth phase, quantifying NH3 concentration and growth rate.

Conclusions:

• Fe-decorated MoS2 sensors offer a promising platform for sensitive and stable NH3 detection.
• This technology enables noninvasive, continuous monitoring of H. pylori growth.
• The study provides a new technological roadmap for early detection and management of H. pylori infections.