< 0.5% cross-reactivity observed with available related molecules.< 50% cross-species reactivity observed with species tested.
Interference observed with 1 or more available related molecules.
The Quantikine Human FLRG Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human FLRG in cell culture supernates, serum, plasma, urine, and human milk. It contains NS0-expressed recombinant human FLRG and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human FLRG showed linear curves that were parallel to the standard curves obtained using the Quantikine kit standards. These results indicate that this kit can be used to determine relative mass values for naturally occurring human FLRG.
Intra-Assay Precision (Precision within an assay) Three samples of known concentration were tested on one plate to assess intra-assay precision.
Inter-Assay Precision (Precision between assays) Three samples of known concentration were tested in separate assays to assess inter-assay precision.
Cell Culture Supernates, Urine
Serum, EDTA Plasma, Heparin Plasma, Human Milk
The recovery of FLRG spiked to levels throughout the range of the assay was evaluated.
Average % Recovery
Cell Culture Media (n=4)
EDTA Plasma (n=4)
Heparin Plasma (n=4)
To assess the linearity of the assay, samples containing high concentrations of FLRG were serially diluted with the appropriate Calibrator Diluent to produce samples with values within the dynamic range of the assay.
Preparation and Storage
Store the unopened product at 2 - 8 °C. Do not use past expiration date.
Background: Follistatin-related Gene Protein/FLRG
Follistatin-related gene protein (FLRG) has been shown to bind and inhibit the TGF-beta family ligands including activin, BMP-2, -6, -7, and GDF-8. FLRG is expressed most highly in heart, lung, kidney, and placenta, and is upregulated by TGF-beta and Activin via Smad proteins.
Entrez Gene IDs
10272 (Human); 83554 (Mouse);
FLRG; FLRGFSRP; follistatin-like 3 (secreted glycoprotein); Follistatin-like 3; Follistatin-like protein 3; Follistatin-related gene protein; follistatin-related protein 3; FSTL3;
Refer to the product for complete assay procedure.
Bring all reagents and samples to room temperature before use. It is recommended that all samples, standards, and controls be assayed in duplicate.
Prepare all reagents, standard dilutions, and samples as directed in the product insert.
Remove excess microplate strips from the plate frame, return them to the foil pouch containing the desiccant pack, and reseal.
100 µL Assay Diluent
Add 100 µL of Assay Diluent to each well.
100 µL Standard, Control, or Sample
Add 100 µL of Standard, control, or sample to each well. Cover with a plate sealer, and incubate at room temperature for 2 hours on a horizontal orbital microplate shaker.
Aspirate each well and wash, repeating the process 3 times for a total of 4 washes.
200 µL Conjugate
Add 200 µL of Conjugate to each well. Cover with a new plate sealer, and incubate at room temperature for 2 hours on the shaker.
Aspirate and wash 4 times.
200 µL Substrate Solution
Add 200 µL Substrate Solution to each well. Incubate at room temperature for 30 minutes on the benchtop. PROTECT FROM LIGHT.
50 µL Stop Solution
Add 50 µL of Stop Solution to each well. Read at 450 nm within 30 minutes. Set wavelength correction to 540 nm or 570 nm.
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but also provides information about sample types, species, and experimental conditions.
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