Human Follistatin ELISA Kit

Product Type:
96 Assays
FST, Follistatin, activin-binding protein, FSH-suppressing protein, FSP, follistatin isoform FST317, FSActivin-binding protein
Research Area:
Cell Biology
Frequently bought together:


Human Follistatin ELISA

Follistatin is a single-chain gonadal protein that inhibits follicle-stimulating hormone release. Activin-binding protein is another name for follistatin. Diseases associated with FST include Orofacial Clefting Syndrome and Polycystic Ovary Syndrome. An important paralog of Follistatin is FSTL3. The Assay Genie Human Follistatin ELISA Kit is a highly sensitive assay for the quantitative measurement of Follistatin in serum, plasma, cell culture supernatant and tissue samples.

system_update_alt Datasheet system_update_alt MSDS

Key Features

Save Time Pre-coated 96 well plate
Quick Start Kit includes all necessary reagents
Publication Ready Reproducible and reliable results


Product Name:

Human Follistatin ELISA Kit

Product Code:



96 Assays


FST, Follistatin, activin-binding protein, FSH-suppressing protein, FSP, follistatin isoform FST317, FSActivin-binding protein

Detection Method:

Sandwich ELISA, Double Antibody


This immunoassay kit allows for the in vitro quantitative determination of Human FST concentrations in serum plasma and other biological fluids.






4°C for 6 months


For Research Use Only

Additional Information


Matrices listed below were spiked with certain level of Human FST and the recovery rates were calculated by comparing the measured value to the expected amount of Human FST in samples.


Recovery Range (%)

Average (%)




EDTA plasma(n=5)



UFH plasma(n=5)




The linearity of the kit was assayed by testing samples spiked with appropriate concentration of Human FST and their serial dilutions. The results were demonstrated by the percentage of calculated concentration to the expected.









EDTA plasma(n=5)




UFH plasma(n=5)





Intra-Assay: CV<8%
Inter-Assay: CV<10%

Kit Components

Component Quantity Storage

ELISA Microplate (Dismountable)

8x12 strips

4°C for 6 months

Lyophilized Standard


4°C/ -20°C

Sample/Standard Dlution Buffer



Biotin-labeled Antibody (Concentrated)


4°C (Protection from light)

Antibody Dilution Buffer



HRP-Streptavidin Conjugate (SABC)


4°C (Protect from light)

SABC Dilution Buffer



TMB Substrate


4°C (Protection from light)

Stop Solution



Wash Buffer (25X)



Plate Sealer



Other materials required:

  • Microplate reader with 450 nm wavelength filter
  • Multichannel Pipette, Pipette, microcentrifuge tubes and disposable pipette tips
  • Incubator
  • Deionized or distilled water
  • Absorbent paper
  • Buffer resevoir

Protein Information


UniProt Protein Function

Binds directly to activin and functions as an activin antagonist. Specific inhibitor of the biosynthesis and secretion of pituitary follicle stimulating hormone (FSH). 2 isoforms of the human protein are produced by alternative splicing.

NCBI Summary

Follistatin is a single-chain gonadal protein that specifically inhibits follicle-stimulating hormone release. The single FST gene encodes two isoforms, FST317 and FST344 containing 317 and 344 amino acids respectively, resulting from alternative splicing of the precursor mRNA. In a study in which 37 candidate genes were tested for linkage and association with polycystic ovary syndrome (PCOS) or hyperandrogenemia in 150 families, evidence was found for linkage between PCOS and follistatin. [provided by RefSeq, Jul 2008]

NCBI GenInfo Identifier:


Molecular Weight:

34,803 Da


*Note: Protocols are specific to each batch/lot. For the exact instructions please follow the protocol included in your kit.

Before adding to wells, equilibrate the SABC working solution and TMB substrate for at least 30 min at 37°C. When diluting samples and reagents, they must be mixed completely and evenly. It is recommended to plot a standard curve for each test.

Step Procedure


Set standard, test sample and control (zero) wells on the pre-coated plate respectively, and then, record their positions. It is recommended to measure each standard and sample in duplicate. Wash plate 2 times before adding standard, sample and control (zero) wells!


Aliquot 0.1ml standard solutions into the standard wells.


Add 0.1 ml of Sample / Standard dilution buffer into the control (zero) well.


Add 0.1 ml of properly diluted sample ( Human serum, plasma, tissue homogenates and other biological fluids.) into test sample wells.


Seal the plate with a cover and incubate at 37 °C for 90 min.


Remove the cover and discard the plate content, clap the plate on the absorbent filter papers or other absorbent material. Do NOT let the wells completely dry at any time. Wash plate X2.


Add 0.1 ml of Biotin- detection antibody working solution into the above wells (standard, test sample & zero wells). Add the solution at the bottom of each well without touching the side wall.


Seal the plate with a cover and incubate at 37°C for 60 min.


Remove the cover, and wash plate 3 times with Wash buffer. Let wash buffer rest in wells for 1 min between each wash.


Add 0.1 ml of SABC working solution into each well, cover the plate and incubate at 37°C for 30 min.


Remove the cover and wash plate 5 times with Wash buffer, and each time let the wash buffer stay in the wells for 1-2 min.


Add 90 µl of TMB substrate into each well, cover the plate and incubate at 37°C in dark within 10-20 min. (Note: This incubation time is for reference use only, the optimal time should be determined by end user.) And the shades of blue can be seen in the first 3-4 wells (with most concentrated standard solutions), the other wells show no obvious color.


Add 50 µl of Stop solution into each well and mix thoroughly. The color changes into yellow immediately.


Read the O.D. absorbance at 450 nm in a microplate reader immediately after adding the stop solution.

Sample Type

When carrying out an ELISA assay it is important to prepare your samples in order to achieve the best possible results. Below we have a list of procedures for the preparation of samples for different sample types.

Sample Type Protocol


If using serum separator tubes, allow samples to clot for 30 minutes at room temperature. Centrifuge for 10 minutes at 1,000x g. Collect the serum fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.

If serum separator tubes are not being used, allow samples to clot overnight at 2-8°C. Centrifuge for 10 minutes at 1,000x g. Remove serum and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles.


Collect plasma using EDTA or heparin as an anticoagulant. Centrifuge samples at 4°C for 15 mins at 1000 × g within 30 mins of collection. Collect the plasma fraction and assay promptly or aliquot and store the samples at -80°C. Avoid multiple freeze-thaw cycles. Note: Over haemolysed samples are not suitable for use with this kit.

Urine & Cerebrospinal Fluid

Collect the urine (mid-stream) in a sterile container, centrifuge for 20 mins at 2000-3000 rpm. Remove supernatant and assay immediately. If any precipitation is detected, repeat the centrifugation step. A similar protocol can be used for cerebrospinal fluid.

Cell culture supernatant

Collect the cell culture media by pipette, followed by centrifugation at 4°C for 20 mins at 1500 rpm. Collect the clear supernatant and assay immediately.

Cell lysates

Solubilize cells in lysis buffer and allow to sit on ice for 30 minutes. Centrifuge tubes at 14,000 x g for 5 minutes to remove insoluble material. Aliquot the supernatant into a new tube and discard the remaining whole cell extract. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C.

Tissue homogenates

The preparation of tissue homogenates will vary depending upon tissue type. Rinse tissue with 1X PBS to remove excess blood & homogenize in 20ml of 1X PBS (including protease inhibitors) and store overnight at ≤ -20°C. Two freeze-thaw cycles are required to break the cell membranes. To further disrupt the cell membranes you can sonicate the samples. Centrifuge homogenates for 5 mins at 5000xg. Remove the supernatant and assay immediately or aliquot and store at -20°C or -80°C.

Tissue lysates

Rinse tissue with PBS, cut into 1-2 mm pieces, and homogenize with a tissue homogenizer in PBS. Add an equal volume of RIPA buffer containing protease inhibitors and lyse tissues at room temperature for 30 minutes with gentle agitation. Centrifuge to remove debris. Quantify total protein concentration using a total protein assay. Assay immediately or aliquot and store at ≤ -20 °C

Breast Milk

Collect milk samples and centrifuge at 10,000 x g for 60 min at 4°C. Aliquot the supernatant and assay. For long term use, store samples at -80°C. Minimize freeze/thaw cycles.

Follistatin Background


Follistatin is a multifunctional protein known for its role in regulating various biological processes, including muscle growth, tissue repair, and inflammation. It acts as a potent inhibitor of myostatin, a negative regulator of muscle mass. Follistatin's ability to bind and neutralize myostatin allows for increased muscle development and enhanced muscle regeneration. In addition, Follistatin has been implicated in other physiological processes, such as embryonic development, fertility, and immune function.

Role of Follistatin

Follistatin plays a crucial role in regulating numerous physiological processes in the body. One of its primary functions is the inhibition of myostatin, a negative regulator of muscle growth. By binding to myostatin and preventing its activity, Follistatin promotes muscle development and increases muscle mass. Follistatin's involvement in muscle regulation has made it a subject of interest in the fields of sports performance and muscle-related disorders. Additionally, Follistatin has been found to have effects beyond muscle growth. It has been implicated in embryonic development, where it participates in patterning and organogenesis. Follistatin also exhibits anti-inflammatory properties, contributing to the regulation of immune responses. Furthermore, Follistatin has been associated with tissue repair and regeneration, suggesting its potential therapeutic applications in promoting healing and recovery. Overall, Follistatin's multifaceted role highlights its significance in various biological processes, making it an intriguing protein for scientific exploration and potential therapeutic interventions

FSTL 3 and Its Importance

FSTL3, also known as Follistatin-like 3, is a protein that plays a significant role in regulating various biological processes. It belongs to the Follistatin family and is structurally similar to Follistatin. FSTL3 acts as a modulator of several signaling pathways, including TGF-β and BMP (Bone Morphogenetic Protein) signaling. By binding to these signaling molecules, FSTL3 regulates their activity and influences cell growth, differentiation, and development. Additionally, FSTL3 has been implicated in cardiovascular health, as it has been shown to regulate cardiac function and protect against adverse remodeling. Its importance lies in its ability to fine-tune signaling pathways and contribute to proper physiological functioning.

Follistatin ELISA FAQs

What is the Follistatin ELISA kit used for?

The Follistatin ELISA kit is a valuable research tool used to quantify the levels of Follistatin protein in various biological samples. It enables researchers to study the role of Follistatin in muscle growth, tissue repair, and inflammation. By accurately measuring Follistatin concentrations, the kit helps researchers gain insights into its involvement in physiological and pathological conditions.

What are the advantages of using the Follistatin ELISA Kit?

The Follistatin ELISA kit offers several advantages for researchers. It provides a highly sensitive and specific method for quantifying Follistatin levels, ensuring reliable and accurate results. The kit is easy to use, with clear instructions and a straightforward protocol. It also offers a wide dynamic range, allowing for the measurement of Follistatin concentrations across a broad spectrum. Furthermore, the Follistatin ELISA kit has been rigorously validated for its performance and reproducibility, ensuring confidence in the obtained data.

What sample types are compatible with the Follistatin ELISA Kit?

The Follistatin ELISA kit is compatible with a variety of sample types, including serum, plasma, cell culture supernatants, and tissue lysates. This versatility enables researchers to analyze Follistatin levels in different biological matrices, facilitating investigations across various research areas

What are the storage requirements for the Follistatin ELISA Kit?

The Follistatin ELISA Kit components should be stored according to the instructions provided in the kit manual. Generally, it is recommended to store the kit components at the recommended temperature to ensure their stability and optimal performance.

What should I do if my assay results are not optimal?

If you encounter any issues or have suboptimal assay results, we recommend contacting our dedicated support team for assistance. They will be available to provide troubleshooting guidance, answer your questions, and ensure you achieve the best possible results with the Follistatin ELISA Kit.