Intended use of the testkit
The Brucella antibody ELISA test kit is designed to identify antibodfies against sugar antigens of Brucella bovis, in serum and milk samples. In contrast to test systems which make use of agglutinating bacterial antigen, this partial monoclonal based ELISA has a very high sensitivity and specificity (according to SAT, E.C. and Weybridge standards).
Principle of the testkit
Diluted milk or serum samples are added to the pre-coated wells. After incubation and appropriate washing a monoclonal anti-bovine IgG antibody conjugate is added and the plates are again incubated. After appropriate washing, substrate is added. After several minutes the color reaction is stopped and the plates are immediately read at 450 nm.
Interpretation of test results
This test can be used in two ways:
- Qualitatively (positive or negative)
– A sample is scored negative if the OD value is lower than 2x OD value of the negative control
– A sample betweeen 2x and 3x the OD value of the negative control is considered weak positive
– A sample above 3x the negative OD value is considered to be positive
- Quantitatively (ELISA units which can be transformed into agglutination units)
– The value in E.C.-units of the samples can be calculated by comparison to their OD-values with a curve which is constructed from the OD-values of the dilutions of the standard (y-axis) and their corresponding values in units (200; 100 ; 50; 25, etc X-axis) on log/log paaper.
With this graphic presentation it is possible to determine the value in units of the samples.
– According to E.C. standards:
* Values below 12,5 IU are considered negative
* Values above 32 IU are considered positive
* Values betweeen 12,5 and 32 IU are considered doubtful