Smartphone-based surface plasmon resonance sensing platform for rapid detection of bacteria

Area of Science:

• * Nanotechnology
• * Analytical Chemistry
• * Microbiology

Background:

• * Bacterial infections present significant public health risks.
• * Current detection methods are often slow, labor-intensive, and require specialized equipment.
• * There is a need for rapid, accessible, and cost-effective bacterial detection techniques.

Purpose of the Study:

• * To develop a novel smartphone-based sensing platform for rapid bacterial detection.
• * To utilize the surface plasmon resonance (SPR) phenomena of gold nanoparticles (AuNPs).
• * To provide an easy-to-use, low-cost, and real-time detection method.

Main Methods:

• * Employed gold nanoparticles (AuNPs) to induce color development via changes in interparticle distance upon bacterial lysate interaction.
• * Captured color development images using a commercial smartphone.
• * Analyzed color signals for bacterial quantification.

Main Results:

• * Achieved a bacterial detection range from 2.44 × 10^5 to 1.25 × 10^8 colony-forming units (cfu) per milliliter (mL).
• * Determined a detection limit of 8.81 × 10^4 cfu/mL.
• * Demonstrated acceptable recoveries (85.7%–95.4%) in spiked real water samples.

Conclusions:

• * The smartphone-based SPR sensing method offers a practical and efficient approach for bacterial detection.
• * Advantages include ease of use, real-time capability, no need for complex equipment, and low cost.
• * The platform shows potential for widespread application in medical, food safety, and environmental monitoring.