Reduced fluoresceinamine as a fluorescent sensor for nitric oxide

Area of Science:

• Analytical Chemistry
• Biomedical Engineering
• Chemical Sensors

Background:

• Nitric oxide (NO) is a critical signaling molecule in biological systems.
• Accurate and rapid detection of NO is essential for research and diagnostics.
• Existing NO sensors may have limitations in sensitivity, speed, or portability.

Purpose of the Study:

• To develop and characterize a new fluorescent sensor for the detection of nitric oxide (NO).
• To evaluate the sensor's performance, including its response range, limit of detection, and precision.
• To assess the sensor's applicability in monitoring NO generation from chemical reactions and compounds.

Main Methods:

• A fluorescent sensor was designed based on the reaction of NO with reduced fluoresceinamine to produce fluorescent fluoresceinamine.
• A portable, stabilized light source (450 nm LED and fiber optics) was utilized.
• The sensor's response was measured in terms of fluorescence intensity over varying NO concentrations.
• Interference studies were conducted with hydrogen peroxide and potassium superoxide.

Main Results:

• The sensor demonstrated a linear response to NO concentrations between approximately 10-750 μM within seconds.
• A low limit of detection (LOD) of about 1 μM for NO was achieved.
• High precision was observed, with a relative standard deviation of less than 1%.
• The sensor successfully monitored NO generated from nitrous acid decomposition and a NO-releasing compound, with no interference from other species under transient conditions.

Conclusions:

• The developed fluorescent sensor provides a rapid, sensitive, and precise method for nitric oxide (NO) detection.
• The portable system is suitable for monitoring NO in various chemical and potentially biological contexts.
• Transient signal measurements effectively mitigate interference from hydrogen peroxide and potassium superoxide.