TABLE 1.
Performance of ELISA and DELFIA in detecting SEB, Y. pestis F1 antigen, and VEE virus
| Parameter | SEB toxin
|
Y. pestis F1 antigen
|
VEE virus
|
|||
|---|---|---|---|---|---|---|
| ELISA | DELFIA | ELISA | DELFIA | ELISA | DELFIA | |
| Assay LOD | 0.625 ng/ml | 0.039 ng/ml | 25 ng/ml | 0.024 ng/ml | 1.25E+07 PFU/mlc | 3.13E+06 PFU/ml |
| % Intraassay variation (n = 3) | <11 | <37 | <13 | <52 | <20 | <18 |
| % Interassay variation (n = 9) | NDa | <52 | ND | <68 | ND | <30 |
| % Intermatrix variation (n) | <20 (6) | <33 (6) | <9 (9) | <26 (9) | <9 (9) | <25 (9) |
| Upper limit of linear range | 10 ng/ml | >10 ng/ml | 500 ng/mlb | >25 ng/ml | 5E+08 PFU/mlb | >5E+07 PFU/ml |
| Lower limit of linear range | 1 ng/ml | 0.039 ng/ml | 50 ng/mlb | 0.024 ng/ml | 5E+07 PFU/mlb | 3.13E+06 PFU/ml |
| % Sensitivity (no. positive/total no.) | ||||||
| Spiked samples | 75 (6/8) | 100 (8/8) | 25 (3/12) | 91.7 (11/12) | 50 (6/12) | 83.3 (10/12) |
| Within LOD | 100 (6/6) | 100 (8/8) | 100 (3/3) | 91.7 (11/12) | 100 (6/6) | 83.3 (10/12) |
| % Specificity (n = 9) | 100 | 100 | 100 | 100 | 100 | 100 |
a
ND, not determined.
b
Based on historical data.
c
That is, 1.25 × 107.