Towards real-time in vitro Enterobacteriaceae beta-lactamase quantification using iridium oxide-based biosensors

Area of Science:

• Clinical Microbiology
• Biosensor Technology
• Antimicrobial Resistance

Background:

• Beta-lactamase-producing Enterobacteriaceae are a growing threat, causing resistance to key antibiotics.
• Existing antimicrobial susceptibility testing (AST) methods struggle to quickly identify beta-lactamase production.
• This can lead to delayed or inappropriate patient treatment.

Purpose of the Study:

• To develop and validate a novel biosensor for rapid detection of beta-lactamase production.
• To assess the performance of the biosensor in identifying resistance in Escherichia coli (E.coli).
• To evaluate the potential of this method for improving diagnostic turnaround times in clinical settings.

Main Methods:

• Development of an iridium oxide-based biosensor.
• In vitro testing of E.coli type strains and genetically modified isolates.
• Clinical validation using 26 E. coli isolates from urinary tract infection patients.

Main Results:

• The biosensor detected beta-lactamase production in E.coli within 10 minutes.
• High reproducibility was observed, with a 6.88% coefficient of variation.
• Clinical validation showed 100% sensitivity, 57% specificity, and 88% accuracy.

Conclusions:

• The novel biosensor provides a rapid, reproducible, and cost-effective method for phenotypic detection of antimicrobial resistance.
• This technology has the potential to significantly reduce diagnostic turnaround times.
• It can support the implementation of individualized antimicrobial susceptibility testing (AST) strategies.