Rapid Antimicrobial Susceptibility Testing with Electrokinetics Enhanced Biosensors for Diagnosis of Acute Bacterial Infections

Abstract

Rapid pathogen detection and antimicrobial susceptibility testing (AST) are required in diagnosis of acute bacterial infections to determine the appropriate antibiotic treatment. Molecular approaches for AST are often based on the detection of known antibiotic resistance genes. Phenotypic culture analysis requires several days from sample collection to result reporting. Toward rapid diagnosis of bacterial infection in nontraditional healthcare settings, we have developed a rapid AST approach that combines phenotypic culture of bacterial pathogens in physiological samples and electrochemical sensing of bacterial 16S rRNA. The assay determines the susceptibility of pathogens by detecting bacterial growth under various antibiotic conditions. AC electrokinetic fluid motion and Joule heating induced temperature elevation are optimized to enhance the sensor signal and minimize the matrix effect, which improve the overall sensitivity of the assay. The electrokinetics enhanced biosensor directly detects the bacterial pathogens in blood culture without prior purification. Rapid determination of the antibiotic resistance profile of Escherichia coli clinical isolates is demonstrated.

Impedimetric measurement of DNA–DNA hybridisation using microelectrodes with different radii for detection of methicillin resistant Staphylococcus aureus (MRSA)

“…Specifically, for the detection of nucleic acids, studies have demonstrated the successful fabrication of microelectode devices using photolithographic methods and the development of nucleic acid sensors which use EIS as the measurement technique. Examples include the detection of BRCA1 gene in breast cancer using interdigitated electrodes 15 the measurement of matched an mismatched DNA for detection of mutations 16 the measurement of 16SrRNA for antibiotic susceptibility testing 17 and the detection of West Nile virus using interdigitated microelectrodes 18 .…”

A UAV-Mounted Whole Cell Biosensor System for Environmental Monitoring Applications

“…Other optical and electrochemical readouts, such as gene expression and metabolic activities, can also be applied to evaluate the response of the cells [16]. The system may also have applications in phenotypic antimicrobial susceptibility testing in the future [17–19]. …”

Electrochemical Detection of RNA

“…Additionally, the biosensor cassette was validated using patient-derived clinical urine samples (Bercovici et al 2012;Mohan et al 2011;Ouyang et al 2013). Liu et al (2014b) applied the electrokinetics-enhanced biosensor platform for rapid antimicrobial susceptibility testing. Patel et al (2011) introduced a target-specific capture sample preparation method enhancing sensitivity of electrochemical 16S rRNA detection.…”