17 α-Hydroxyprogesterone ELISA kit

Sample

Saliva

Species Reactivity

Human

Intended Use

The Salivary 17 α-Hydroxyprogesterone (17α-OHP) ELISA Kit is An enzyme immunoassay for the quantitative measurement of active free 17-hydroxyprogesterone in saliva.

Contents of Kit

1. ##Microtiterwells##, 12 x 8 (break apart) strips, 96 wells;
2. ##Standard (Standard 0-5)##, 6 vials, 1 mL, ready to use;
3. ##Control Low & High##, 2 vials, 1.0 mL each, ready to use;
4. ##Enzyme Conjugate##, 1 vial, 26 mL, ready to use;
5. ##Substrate Solution##, 1 vial, 25 mL, ready to use;
6. ##Stop Solution##, 1 vial, 14 mL, ready to use;

Storage

2°C to 8°C

Performance Characteristics

##Assay Dynamic Range##
The range of the assay is between 3.6 - 1000 pg/mL.

##Specificity of Antibodies (Cross Reactivity)##
The following materials have been evaluated for cross reactivity. The percentage indicates cross reactivity at 50% displacement compared to 17α-OHP.


##Sensitivity##
The analytical sensitivity of the CD ELISA was calculated by subtracting 2 standard deviations from the mean of 20 replicate analyses of the Zero Standard (S0).
Analytical sensitivity is: 2.5 pg/mL
Functional sensitivity of the assay is: 3.6 pg/mL

##Reproducibility##
##Intra-Assay##
The intra-assay reproducibility was determined by replicate measurements of 6 saliva samples using CD ELISA kit. The within assay precision is shown below:


##Inter-Assay##
The inter-assay variation was determined by duplicate measurements of six saliva samples on 10 different days using this ELISA kits. Mean of the duplicate measurements is given below.


##Inter-Lot##
The inter-assay (between-lots) variation was determined by repeated measurements of six saliva samples in three different kit lots.


##Recovery##
Recovery of the CD ELISA was determined by adding increasing amounts of the analyte up to 500 pg/mL to three different saliva samples containing different amounts of endogenous analyte. Each sample (non-spiked and spiked) was assayed and analyte concentrations of the samples were calculated from the standard curve. The percentage recoveries were determined by comparing expected and measured values of the samples.


##Linearity##
Six saliva samples containing different amounts of analyte (spiked and unspiked) were serially diluted with zero standard and assayed with the CD ELISA. Three native samples were serially diluted up to 1:128, and 3 samples were spiked with 17α-OHP and then serially diluted up to 1:10. The percentage recovery was calculated by comparing the expected and measured values for 17α-OHP. An assay linearity of 3.6 - 1000 pg/mL has been identified as the usable range. Samples above this range must be diluted and re-run.

General Description

The steroid 17-α-Hydroxyprogesterone (17-α-OHP) is produced by both the adrenal cortex and gonads. Even though 17α-OHP has relatively little progestational activity, it is of intense clinical interest because it is the immediate precursor to 11-desoxycortisol (Cpd-S). Because Cpd-S is produced by 21-hydroxylation of 17-α-OHP, measurement of 17-α-OHP is a useful indirect indicator of 21-hydroxylase activity. In congenital 21-hydroxylase deficiency, the most common variety of Congenital Adrenal Hyperplasia (CAH), 17-α-OHP is secreted in abundant excess. It is moderately elevated in the 11β-hydroxylase deficiency as well. Measurement of 17-α-OHP is therefore valuable in the initial diagnosis of CAH.

Standard Curve

##Standard## ##Optical Units (450 nm)##
Standard 0 (0 pg/mL) 1.92
Standard 1 (10 pg/mL) 1.72
Standard 2 (50 pg/mL) 1.47
Standard 3 (250 pg/mL) 0.91
Standard 4 (500 pg/mL) 0.64
Standard 5 (1000 pg/mL) 0.41

Reconstitution And Storage

When stored at 2°C to 8°C unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date. Opened reagents must be stored at 2°C to 8°C. Microtiter wells must be stored at 2°C to 8°C. Once the foil bag has been opened, care should be taken to close it tightly again. Opened kits retain activity for six weeks if stored as described above.