A Novel Methylene Blue Indicator-Based Aptasensor for Rapid Detection of Pseudomonas aeruginosa

Area of Science:

• Biomedical Engineering
• Environmental Science
• Analytical Chemistry

Background:

• Pseudomonas aeruginosa is a prevalent opportunistic pathogen requiring early detection to prevent infections.
• The F23 aptamer offers high specificity for P. aeruginosa, enabling sensor development.
• Existing detection methods can be time-consuming or lack sensitivity.

Purpose of the Study:

• To develop a novel, highly sensitive, and selective electrochemical aptasensor for P. aeruginosa detection.
• To utilize disposable gold screen-printed electrodes (Au-SPEs) for reproducible sensor fabrication.
• To employ methylene blue (MB) as an indicator for signal amplification.

Main Methods:

• Fabrication of an F23-based electrochemical aptasensor on Au-SPEs.
• Integration of methylene blue as an electrochemical signal indicator.
• Testing the aptasensor's limit of detection (LOD) and selectivity against common bacteria.
• Validation of the aptasensor's performance in real-world environmental samples (tap water).

Main Results:

• The aptasensor demonstrated high reproducibility and sensitivity.
• Achieved a low limit of detection (LOD) of 8 CFU·mL⁻¹ for P. aeruginosa.
• Exhibited excellent selectivity, distinguishing P. aeruginosa from other bacterial species.
• Successfully detected P. aeruginosa in spiked tap water samples.

Conclusions:

• The developed F23-based electrochemical aptasensor is a promising tool for rapid and sensitive P. aeruginosa detection.
• The use of Au-SPEs and MB enhances sensor performance, making it suitable for point-of-care applications.
• This technology can aid in controlling P. aeruginosa growth in various environmental settings.