Design and characteristic of CMOS fabricated acoustic waves based sensors for foodborne pathogen rapid detection

The issue of food contamination by pathogens has become extreme serious due to the insensitive detection techniques. Escherichia coli O157:H7 is one of the harmful bacterial pathogens which is distributed in soil, marine and estuarine waters, the intestinal tract of animals, or water contaminated with fecal matter. Escherichia coli O157:H7, is an enterohaemorrhagic strain of the bacterium Escherichia coli (E.coli) and a cause of foodborne illness. It can cause serious human gastrointestinal disease. A small amount of E.coli with the dose fewer than 100 organisms in food products or water is enough to cause serious illness to human. Therefore, there is a need for a more sensitive, rapid method and yet a cost effective method to examine the food and environment safety. In this case, there are many CMOS fabricated acoustic waves based technologies which are initially designed for telecommunication applications and have been developed for pathogen detection recently due to their ultra-sensitivity to the surface changes. This paper reviews the detection of E.coli (one of the dangerous food pathogens), the design, characteristic and types of CMOS fabricated acoustic wave-based methods, typically surface acoustic waves (SAW) as for their label free, selective and ultra-sensitive detection and also their advantages over the current equipment such as surface plasmon resonance (SPR) and quartz crystal microbalances (QCM). Besides that, the elements and principle of SAW sensors are explored in E.coli DNA detection and the advantages of DNA probe over antibody probe. It also highlights the limitations of some types of acoustic waves based sensors for the E.coli detection.