Cost-Efficient Micro-Well Array-Based Colorimetric Antibiotic Susceptibility Testing (MacAST) for Bacteria from...

Area of Science:

• Microbiology
• Biotechnology
• Medical Diagnostics

Background:

• Current antibiotic susceptibility testing (AST) methods face challenges in throughput, cost-effectiveness, and applicability to microbial communities.
• Timely and precise antibiotic prescriptions are crucial for effective treatment and combating antimicrobial resistance.

Purpose of the Study:

• To develop a high-throughput, cost-efficient colorimetric AST system for both individual bacterial strains and complex microbial communities.
• To significantly reduce the time and cost associated with bacterial isolation and susceptibility testing.

Main Methods:

• Development of a micro-well array-based colorimetric AST (macAST) system with a smartphone application for testing multiple bacteria-antibiotic combinations.
• Integration of immunomagnetic separation with macAST (imacAST) for rapid enrichment of target bacteria from community samples.
• Utilized resazurin metabolism assay for colorimetric readout of bacterial viability and antibiotic susceptibility.

Main Results:

• The macAST system achieved comparable AST results to existing methods, testing sixteen combinations simultaneously.
• The imacAST system reduced bacterial isolation time from days to 45 minutes, enabling AST for low bacterial concentrations (~10^3 CFU/mL).
• The system provided antimicrobial susceptibility results within 6 hours, a significant improvement over traditional methods requiring days.

Conclusions:

• The developed high-throughput AST system offers a cost-effective and rapid solution for determining antimicrobial susceptibility.
• The imacAST approach enables efficient analysis of microbial communities, overcoming limitations of traditional methods.
• This technology has the potential to improve antibiotic stewardship, especially in resource-limited settings, by enabling faster, more precise treatment decisions.