Most nucleic acid-based sensors for the detection of generic E. coli have targeted recognition based on RNA, more specifically 16S ribosomal RNA (rRNA) region . 16S rRNA is a part of the 30S subunit of prokaryotic ribosome containing a highly conserved region within the same group of microorganisms, due to its low rate of evolution., However, the use of 16S rRNA to differentiate between E. coli and Shigella spp. is not possible due to the >99% sequence similarity . Therefore, the sensors developed based on 16S rRNA detection are not considered specific for E. coli . The electrochemical sensors developed for the detection of generic E. coli based on DNA recognition have typically focused on targeting the uidA gene responsible for the ß-glucuronidase enzyme . This enzyme catalases the breaking of the glycosidic bond and was reported to be specific for E. coli. However, similarly to 16s rRNA, targeting only this gene would not differentiate E. coli from Shigella spp which can also contain it in its genome .