Ultrasonic atomizer based development of pH sensor for real time analysis.

Area of Science:

• Biotechnology
• Chemical Sensing
• Food Science

Background:

• Conventional pH meters are costly and unsuitable for continuous real-time monitoring.
• Fluorescent pH biosensors offer a low-cost alternative for analyzing biological and food samples.
• Real-time monitoring is crucial for assessing the quality and safety of perishable goods like milk.

Purpose of the Study:

• To develop a novel fluorescent pH biosensor for real-time analysis using ultrasonic atomization.
• To immobilize indicator and reference fluorophores within alginate microspheres for enhanced pH sensing.
• To evaluate the biosensor's performance in monitoring milk spoilage.

Main Methods:

• Fabrication of dye-immobilized alginate microspheres via ultrasonic atomization.
• Utilizing Fluorescein isothiocyanate (FITC)-dextran as the indicator fluorophore.
• Incorporating FITC-dextran-Tris (2, 2'-bipyridyl) dichlororuthenium (II) hexahydrate as the reference fluorophore.
• Testing the biosensor's accuracy and response time on milk samples.

Main Results:

• The biosensor demonstrated efficient pH sensing with monodisperse dye-immobilized alginate microspheres.
• A linear pH detection range of 4-8 was achieved (R² = 0.96-0.99).
• The biosensor showed high accuracy (% recovery 90-110%) and a low turnaround time (10 minutes) compared to standard pH meters.

Conclusions:

• The developed fluorescent pH biosensor provides a viable, cost-effective solution for real-time monitoring of milk quality.
• This technology can significantly reduce economic losses in food processing and storage.
• The biosensor enables continuous, in-package quality assessment, enhancing food safety and shelf-life management.