The detection time of assays presented in this review vary from 1 to 7 hours, depending on the technique used, sample preparation and if any amplification or enrichment methods were used. Since the traditional microbiological methods take a few days for analysis, these biosensors provide an advantage in terms of the analysis period. However, their use in the collected literature was typically limited to pure bacteria culture that only provide a proof-of-concept results. The complex samples such as faeces or food samples may contain low numbers of E. coli or STEC in the presence of other bacteria with high numbers. In that case, the use of an amplification method or enrichment, the common ways to increase the number of target DNA in the sample, may be necessary. This would, however, increase the complexity and time-to-results of the assay.