This assay employs the competitive inhibition enzyme immunoassay technique. The microtiter plate provided in this kit has been pre-coated with T4 protein. Standards or samples are added to the appropriate microtiter plate wells then with a biotin-conjugated antibody specific to T4. Next, Avidin conjugated to Horseradish Peroxidase (HRP) is added to each microplate well and incubated. After TMB substrate solution is added. The enzyme-substrate reaction is terminated by the addition of sulphuric acid solution and the color change is measured spectrophotometrically at a wavelength of 450nm ± 10nm. The concentration of T4 in the samples is then determined by comparing the OD of the samples to the standard curve.
標(biāo)準(zhǔn)曲線
Concentration (ng/mL)
OD
Corrected OD
300.00
0.227
150.00
0.386
75.00
0.575
37.50
0.812
18.75
1.157
9.38
1.537
4.69
1.775
0.00
2.211
精密度
Intra-assay Precision (Precision within an assay):CV%<8%
Three samples of known concentration were tested twenty times on one plate to assess intra-assay precision.
Inter-assay Precision (Precision between assays):CV%<10%
Three samples of known concentration were tested in forty separate assays to assess inter-assay precision.
回收率
Matrices listed below were spiked with certain level of recombinant T4 and the recovery rates were calculated by comparing the measured value to the expected amount of T4 in samples.
Matrix
Recovery range
Average
serum(n=5)
83-95%
89%
EDTA plasma(n=5)
86-98%
92%
Heparin plasma(n=5)
95-107%
101%
線性
The linearity of the kit was assayed by testing samples spiked with appropriate concentration of T4 and their serial dilutions. The results were demonstrated by the percentage of calculated concentration to the expected.