PIEZOELECTRIC BIOSENSOR FOR DETECTION OF SALMONELLA-TYPHIMURIUM

A flow injection analysis (FIA) system was developed based on a piezoe lectric biosensor for detection of Salmonella typhimurium. The anti-Sa lmonella spp antibody was immobilized onto the gold electrode coated q uartz crystal surface through a polyethylenimine-glutaraldehyde (PEG) technique and dithiobis-succinimidyl propionate (DSP) coupling. The PE G technique proved more successful for FIA applications than the DSP c oupling. The biosensor had responses of 23-47 Hz in 25 min when the PE G immobilization technique was employed, with R-2>0.94 for Salmonella typhimurium concentrations of 5.3x10(5) to 1.2x10(9) CFU/mL.