Abstract: The present invention provides an assay for detection of M. bovis-infected animals. A tracer, comprising a peptide of M. bovis protein MPB70 conjugated to a fluorophore, is added to a serum sample from an animal to form a mixture. The fluorescence polarization of the mixture in then measured and compared to the fluorescence polarization of a control. The present invention further provides a tracer for use in fluorescence polarization assay to detect antibodies specific for M. bovis. The tracer comprises a peptide of M. bovis protein MPB70 conjugated to a fluorophore, such that the tracer is able to bind to antibodies specific for M. bovis to produce a detectable change in fluorescence polarization.

Abstract: The present invention provides an assay for detection of serum antibodies to M. paratuberculosis. A tracer, comprising a carbohydrate antigen isolated from M. paratuberculosis that is conjugated to a fluorophore, is added to a serum sample from an animal to form a mixture. The fluorescence polarization of the mixture is then measured. The presence of serum antibodies to M. paratuberculosis is indicated by a fluorescence polarization value of the mixture that is higher than the fluorescence polarization value of a control. The present invention further provides a tracer for use in a fluorescence polarization assay for antibodies specific for M. paratuberculosis. The tracer comprises a carbohydrate antigen isolated from M. paratuberculosis and conjugated to a fluorophore, such that the tracer is able to bind to antibodies specific for M. paratuberculosis to produce a detectable change in fluorescence polarization.

Abstract: A method for electrochemical detection (ECD) is disclosed. The illustrated embodiments are particularly adapted to use in detection of analytes separated by capillary electrophoresis. The method is a voltammetric ECD, including a preparatory positive potential pulse, an optional stabilizing pulse at a negative potential, an analytical pulse at extreme negative potentials (e.g., −300 mV to −1,500 mV), and a positive cleaning potential pulse. The methods have been shown to detect analytes previously considered to be electrochemically inactive using more traditional electrochemical methods. Examples of such analytes include various drugs, antibiotics, and peptides.