This study presents the development of phage mediated quartz crystal microbalance (QCM) sensor for the detection of Escherichia coli. Bacteriophage is very specific to host bacterial cell also known as parasite for bacteria. The Electrochemical Quartz Crystal Microbalance (EQCM) is a very sensitive device that measures a mass change per unit area by measuring the change in resonant frequency of a quartz crystal. A self-assembled monolayer (SAM) of 11-mercaptoundecanoic acid (MUA)/ 1-ethyl-3-[3-dimethylami-nopropyl] carbodiimide hydrochloride (EDC)/hydroxysuccinimide (NHS) is incorporated for the covalent attachment of phage to the gold surface of the piezoelectric crystal. A Sauerbrey increase in frequency is observed upon exposure of such a crystal surface modified for phage to E. coli cells. Electrochemical cell was provided with the module oscillation frequency of 6 MHz. This unexpected response is reliable with the obtained results and is shown to be specific. The sensor can detect E. coli cells in real time in solution to 1 × 105 cfu/ml.

Keywords: Bacteriophage, electrochemical, frequency, quartz crystal, monolayer