Highly sensitive phage-based biosensor for the detection of beta-galactosidase

Area of Science:

• Biotechnology
• Biosensor Development
• Surface Plasmon Resonance Spectroscopy

Background:

• Real-time sensors for antigen detection are crucial for various applications.
• Bacterial phage offer high specificity, stability, and ease of production for biosensor probes.

Purpose of the Study:

• To develop a highly sensitive and specific label-free biosensor for detecting beta-galactosidase (beta-gal).
• To utilize bacterial phage as a biorecognition element in a surface plasmon resonance (SPR) biosensor.

Main Methods:

• Immobilization of beta-gal specific phage (1G40) on an SPR sensor chip.
• Detection of beta-gal using SPR spectroscopy in both flow-through and batch modes.
• Assessment of sensor specificity through competitive inhibition assays.

Main Results:

• Achieved sensitive and specific label-free detection of beta-gal from 10(-12) M to 10(-7) M.
• Flow-through mode demonstrated higher sensitivity and more consistent results compared to batch mode.
• Determined binding affinity (K(d)) and valency for both sensing modes.

Conclusions:

• Bacterial phage are effective biorecognition probes for SPR-based biosensors.
• The developed phage-SPR biosensor offers a sensitive and specific platform for antigen detection.
• Flow-through mode is superior for real-time, sensitive antigen monitoring.