**Abstract**

Detection and identification of pathogenic bacteria is important in the field of public health, medicine, food safety, environmental monitoring and security. Worldwide, the common cause of mortality and morbidity is bacterial infection often due to misdiagnosis or delay in diagnosis. Existing bacterial detection methods rely on conventional culture or microscopic techniques and molecular methods that often time consuming, laborious and expensive, or need trained users. In recent years, biosensor remained an interesting topic for bacterial detection and many biosensors involving different bio-probes have been reported. Compared to antibodies, nucleic acids and enzymes etc., based biosensors, bacteriophages can be cheaply produced and are relatively much stable to elevated temperature, extreme pH, and diverse ionic strength. Therefore, there is an urgent need for phage-based biosensor for bacterial pathogen detection. Furthermore, bearing high affinity and specificity, bacteriophages are perfect bio-recognition probes in biosensor development for bacterial detection. In this regard, active and oriented phages immobilization is the key step toward phage-based biosensor development. This chapter compares different bacterial detection techniques, and introduces the basic of biosensor and different bio-probes involved in biosensor development. Further we highlight the involvement and importance of phages in biosensor and finally we briefed different phage immobilization approaches used in development of phagebased biosensors.

**Keywords:** biosensor development, bacterial detection techniques, bio-probes, phage-probe, phage immobilization
