**4. Bacteriophages in biosensor**

A phage as a bio-recognition probe offers numerous benefits in rapid bacterial sensing [17] as they are: (•) extremely specific to their host [26], (•) ability of producing extraordinary titers of descendant phages, (•) tolerant to extreme environmental conditions like ultrahigh temperatures, organic solvents and wide-ranging pH compared to Abs, [27], (•) safe handling, (•) discriminating among dead and live bacteria as they proliferate only in live bacterial cells [28], (•) production in bulk are artless and economical. These compensations make phages as leading bio-recognition probes to develop biosensors for bacterial screening [15]. Frequently designed phage-based biosensor schemes comprise the association of whole phage or phage-constituents, infecting/capturing target bacterial cells and ultimately resulting in the production of electrical, colorimetric, fluorescent, or luminescent etc. signals, based on the available biosensing system. Hence, phages are demonstrating themselves as novel troupes for cheap, fast, sensitive and specific bacterial detection in comparison to other available platforms [29].
