Instantaneous Antimicrobial Susceptibility Testing Using Piezoelectric Sensors

Rapid determination of drugs effective against bacterial strains is critically important to stopping further spread of an infection and reducing antibiotic resistance. Antimicrobial susceptibility testing (AST) is done to determine what type of antibiotic and what concentration will be effective in treating an infection. Current, growth-dependent, AST methods are reliant on the growth rate of the bacteria and can take several days to several weeks to get results. A piezoelectric plate sensor can be used to measure an instant change in the minute physiological stresses of the bacteria cells when they are exposed to an effective concentration of antibiotic. This work aims to investigate the feasibility of piezoelectric plate sensors used for instantaneous AST (iAST) results and develop a technological framework for scaling this technology to a clinical lab setting. Four Clinical and Laboratory Standards Institute (CLSI) quality control strains of bacteria were tested with a wide range of antibiotics from various drug classes using the piezoelectric sensor. Results were obtained within 30 minutes and compared to standard of care AST methods used in clinical labs, and CLSI prescribed ranges for each strain of bacteria. This thesis will also discuss a framework for developing more scalable sensors, and challenges associated with the different sensor designs.