IMMUNOELECTROCHEMICAL ASSAYS FOR BACTERIA - USE OF EPIFLUORESCENCE MICROSCOPY AND RAPID-SCAN ELECTROCHEMICAL TECHNIQUES IN DEVELOPMENT OF AN ASSAY FOR SALMONELLA
Jd. Brewster et al., IMMUNOELECTROCHEMICAL ASSAYS FOR BACTERIA - USE OF EPIFLUORESCENCE MICROSCOPY AND RAPID-SCAN ELECTROCHEMICAL TECHNIQUES IN DEVELOPMENT OF AN ASSAY FOR SALMONELLA, Analytical chemistry, 68(23), 1996, pp. 4153-4159
Immunoelectrochemical sensors in which the sensor surface functions as
both analyte capture phase and electrochemical detector have recently
been developed for bacteria analysis. The speed and sensitivity of th
ese devices make them very attractive for applications such as the det
ection of pathogenic microorganisms in food and water. However, the de
velopment and optimization of assays utilizing these sensors can be co
mplicated by undesired interactions between the capture and detection
functions. Modification of the sensor to achieve improvements in one f
unction can have deleterious effects on the other function, and such e
ffects can be difficult to diagnose and correct. In the course of inve
stigations on immunoelectrochemical detection of Salmonella, we develo
ped a rapid, nondestructive epifluorescence microscopy method to deter
mine bacteria capture efficiency. This method enabled us to study capt
ure and detection functions independently and efficiently identify per
formance-limiting factors. Rapid-scan electrochemical methods were use
d to optimize detection sensitivity and to provide diagnostic informat
ion on detection performance.