Rapid Electrochemical Monitoring of Bacterial Respiration for Gram-Positive and Gram-Negative Microbes: Potential Application in Antimicrobial Susceptibility Testing

Abstract

Antimicrobial resistance is a grave threat to human life. Currently used time-consuming antibiotic susceptibility test (AST) methods limit physicians in selecting proper antibiotics. Hence, we developed a rapid AST using electroanalysis with a 15 min assay time, called EAST, which is live-monitored by time-lapse microscopy video. The present work reports systematical electrochemical analysis and standardization of protocol for EAST measurement. The proposed EAST is successfully applied for Gram-positive Bacillus subtilis and Gram-negative Escherichia coli as model organisms to monitor bacterial concentration, decay kinetics in the presence of various antibiotics (ciprofloxacin, cefixime, and amoxycillin), drug efficacy, and IC50. Bacterial decay kinetics in the presence of antibiotics were validated by the colony counting method, field emission scanning electron microscopy, and atomic force microscopy image analysis. The EAST predicts the antibiotic susceptibility of bacteria within 15 min, which is a significant advantage over existing techniques that consume hours to days. The EAST was explored further by using bacteria-friendly l-lysine-functionalized cerium oxide nanoparticle coated indium tin oxide as a working electrode to observe the enhanced electron-transfer rate in the EAST. The results are very significant for future miniaturization and automation. The proposed EAST has huge potential in the development of a rapid AST device for applications in the clinical and pharmaceutical industries.

Recent Advances in the Detection of Antibiotic and Multi-Drug Resistant Salmonella: An Update

“…Other groups continue to use this inexpensive, highly sensitive approach in the detection of Salmonella. Recently, L-lysine functionalized cerium oxide nanoparticle coated indium tin oxide (L-CeONP/ITO) electrodes were used instead of solid nanoAg to predict the susceptibility of gram-negative bacteria in less than 15 min via cyclic voltammetry with minimal ROS interference [97]. Changes in the anodic peak current response of optimized bacteria before and after the treatment of antibiotics were considered as antibiotic susceptible by the authors.…”

Progressing Antimicrobial Resistance Sensing Technologies across Human, Animal, and Environmental Health Domains

“…Several groups have employed sensors within microwells to track electrical changes in response to microbial growth or NA amplification. − Safavieh et al made use of immobilized antibodies for on-chip separation of bacteria from complex matrices such as blood and urine (Figure C). Importantly, this sample-agnostic technique allowed for AST to be performed directly on spiked samples within 90 min, making it useful for a variety of sample types in the human health domain.…”

Antimicrobial resistance. Characteristic of resistance to antimicrobial preparations of Gram-negative bacteria

“…Este elaborată metoda rapidă de testare a sensibilității la antibiotice prin electroanaliză, cu o durată de 15 minute, care este monitorizată în direct prin video-microscopie. Metoda propusă a fost aplicată cu succes pentru Bacillus subtilis Grampozitive și Escherichia coli Gram-negative [21].…”