A Hybrid Electrokinetic Bioprocessor For Single-Cell Antimicrobial Susceptibility Testing

Abstract

Infectious diseases resulting from bacterial pathogens are the most common causes of patient morbidity and mortality worldwide. The rapid identification of the pathogens and their antibiotic resistances is crucial for proper clinical management. However, the standard culture-based diagnostic approach requires a minimum of two days from the initial specimen collection to result reporting. As a consequence, broad-spectrum antibiotics are often prescribed under the worst-case assumption without knowledge of the pathogens or their resistances. The current clinical practice results in improper treatment of the patient and causes the rapid emergence of multi-drug resistant pathogens. A rapid diagnostics system has therefore been developed which performs hybrid electrokinetic sample preparation and volume reduction, for single-cell antimicrobial susceptibility testing (AST). The system combines multiple electrokinetic forces for sample preparation, which reduces the sample volume for over 3 orders of magnitude and minimizes the matrix effects of physiological samples for enhanced sensitivity. The device is integrated with a single-cell AST system with microfluidic confinement and electrokinetic loading to phenotypically determine the bacterial antibiotic resistance at the single-cell level. The applicability of the system has been demonstrated for performing direct AST with urine and blood samples within one hour, enabling rapid infectious disease diagnostics in non-traditional healthcare settings.