Development of Integrated Systems for On-Site Infection Detection

Area of Science:

• Biotechnology and Biomedical Engineering
• Infectious Disease Diagnostics
• Point-of-Care Testing

Background:

• The healthcare system faces significant threats from microbial infections, including viral outbreaks, antimicrobial resistance, and healthcare-associated infections (HAIs).
• Current diagnostic methods often lack the speed and accessibility required for effective point-of-care (POC) settings, leading to diagnostic uncertainty and delayed treatment.
• Culture-based and centralized nucleic acid tests are time-consuming and require specialized infrastructure, hindering rapid clinical decision-making.

Purpose of the Study:

• To develop and evaluate novel point-of-care (POC) diagnostic tests for rapid and accurate identification of infectious agents.
• To address the limitations of existing diagnostic methods by creating faster, more cost-effective, and accessible testing solutions.
• To validate the clinical applicability of these new diagnostic technologies in real-world healthcare scenarios.

Main Methods:

• nanoPCR: Utilizes core-shell magnetoplasmonic nanoparticles (MPNs) with a gold shell for accelerated thermocycling via light-to-heat conversion and a magnetic core for sensitive in situ fluorescent detection.
• Polarization Anisotropy Diagnostic (PAD): Employs fluorescence polarization to detect changes in probe tumbling rates upon target nucleic acid recognition, offering robust and ratiometric signal readout.
• Both systems were tested using clinical samples, including COVID-19 patient samples and clinically relevant HAI bacteria, assessing their sensitivity, speed, and accuracy.

Main Results:

• nanoPCR detected SARS-CoV-2 RNA down to 3.2 copy/μL in 17 minutes, demonstrating high accuracy in clinical COVID-19 samples (n=150).
• PAD achieved single-bacterium level detection sensitivity for key HAI bacteria (E. coli, K. pneumoniae, A. baumannii, P. aeruginosa, S. aureus) and identified drug resistance and virulence.
• Both nanoPCR and PAD assays are rapid, cost-effective, and do not require highly skilled personnel or complex laboratory setups.

Conclusions:

• nanoPCR and PAD represent powerful new tools for rapid infectious disease diagnosis at the point of care.
• These technologies overcome limitations of traditional methods, enabling faster and more informed clinical decisions.
• The developed POC tests have the potential to significantly improve patient management by facilitating prompt and targeted antimicrobial treatment.