All tags SimpleStep ELISA kit buyer’s guide

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ELISA kit buyer’s guide

The product data you need to look for when purchasing an ELISA kit.


When using an ELISA kit, you want specific, accurate, sensitive, and reproducible results. To be sure your kit can deliver this, it’s important to have access to the validation data before you make a purchase. However, the kits on the market range from having no validation to a full biological validation. Different levels of validation will influence the type of data available, so it’s important to know what you need at the start. See the table below for the validation break down.

Table 1. The types of product data available with different levels of ELISA kit validation.

Product dataNo validationLimited validationFull validation
Dynamic range✓ ✓ ✓ 
Sensitivity✓ ✓ ✓ 
Precision (intra/inter-assay CV)✓ ✓ ✓ 
Standard curve
✓ ✓ 
Spike recovery
✓ ✓ 
Spike linearity
✓ ✓ 
Biological samples

✓ 
Antibody pair cross-reactivity

✓ 
Alternative species reactivity

✓ 
International standard (NIBSC/WHO)

✓ 


What are these data important for my experiment?

Product dataWhy is it useful?
Dynamic rangeAllows you to see that the kit is capable of detecting and quantifying your expected protein concentrations.
SensitivityShows the lowest level of protein that the antibody pair is able to detect. It should always be less than the lowest point of the standard curve. 
PrecisionShows you how consistent the assay is between runs. A good kit could have a CV < 10%.
Standard curveVisual confirmation that the curve is not a low or flat curve. A poor standard curve means the antibody didn’t bind properly or doesn’t capture the protein standard. The R2 value of the trend line should be >0.99.
Spike-and-recoveryTells you that a target protein is recoverable after being spiked into a matrix. Acceptable results are 80–120%.
LinearityPoor linearity of dilution indicates that the natural sample matrix, the sample diluent and/or standard diluent affect protein detectability differently.
Biological samplesEvidence that the antibody pair detects the endogenous protein and not just the recombinant protein.
Species cross-reactivityGives you an indication of extent to which an antibody pair binds to non-target proteins. This should ideally be <5%.
International standardCalibration to an international control enables cross-comparison between data sets. This helps you switch from an ELISA supplier to another one for the same ELISA kit.

Example: Human IL-8 SimpleStep ELISA® kit

Human IL-8 ELISA kits are available from various ELISA suppliers but not all of them have been fully validated. When buying a kit, you need to carefully evaluate all of the available data.
Table 2. Comparison of different human IL-8 ELISA kits available on the market

Human IL-8 ELISA kits are available from various ELISA suppliers but not all of them have been fully validated. When buying a kit, you need to carefully evaluate all of the available data.

Table 2. Comparison of different human IL-8 ELISA kits available on the market

Product dataCompetitor A ELISA kitCompetitor B ELISA kitCompetitor C ELISA kitAbcam SimpleStep ELISA® kit (ab214030)
Dynamic range (pg/mL)15.6–1,0001–60031.2–2,0003.9–250
Sensitivity (pg/mL)817.51.8
Precision
✓ ✓ ✓ 
Standard curve
✓ ✓ ✓ 
Spike-and-recovery
✓ ✓ ✓ 
Linearity
✓ ✓ ✓ 
Biological samples

✓ ✓ 
Species cross-reactivity

✓ ✓ 
International standard

✓ ✓ 
Assay time4 h 30 min5 h3 h 30 min90 min

Our SimpleStep ELISA kit (ab214030) in this example shows comparable sensitivity but also offers a complete spectrum of product data to give you confidence about the assay’s performance and reliability. It also delivers results in a fraction of the time.