Quantum dots are nearly spherical nanocrystals that have unique optical property which are in intermediate in size between bulk semiconductor and individual atom. Lead sulphide (PbS) nanoparticles are synthesized by the reaction between lead nitrate and sodium sulphide. This paper proposes a detection method of bacterial sample based on memristic properties of semiconductor quantum dots. In this case, PbS nanoparticle is considered for its good fluorescent property. PbS nanoparticle were synthesized and characterized by UV –visible spectroscopy, PL, XRD, SEM and HRTEM. The antimicrobial activity of Pbs and CdS quantum dots are observed in this paper. The potential application of these quantum dots as a biosensor is examined by conjugating bacterial stain E. coli and S. aureus and examining the current –voltage characteristics with E. coli.

Keywords: Lead Sulphide (PbS); Semiconductor; Antimicrobial Activity;