• Product name
    Human C Reactive Protein ELISA Kit
    See all C Reactive Protein kits
  • Detection method
  • Precision
    Sample n Mean SD CV%
    Human serum 5 1.5%
    Sample n Mean SD CV%
    Human serum 3 7.2%
  • Sample type
    Cell culture supernatant, Serum, Heparin Plasma, EDTA Plasma, Citrate Plasma
  • Assay type
    Sandwich (quantitative)
  • Sensitivity
    4 pg/ml
  • Range
    15.63 pg/ml - 1000 pg/ml
  • Recovery

    90.1 %

    Sample specific recovery
    Sample type Average % Range
    Cell culture media 90.1 88.3% - 93.4%

  • Assay time
    1h 30m
  • Assay duration
    One step assay
  • Species reactivity
    Reacts with: Human
  • Product overview

    Abcam’s C-Reactive Protein (CRP) in vitro SimpleStep ELISA® (Enzyme-Linked Immunosorbent Assay) kit is designed for the quantitative measurement of CRP protein in Human cell culture supernatant, serum and plasma samples.

    The SimpleStep ELISA® employs an affinity tag labeled capture antibody and a reporter conjugated detector antibody which immunocapture the sample analyte in solution. This entire complex (capture antibody/analyte/detector antibody) is in turn immobilized via immunoaffinity of an anti-tag antibody coating the well. To perform the assay, samples or standards are added to the wells, followed by the antibody mix. After incubation, the wells are washed to remove unbound material. TMB substrate is added and during incubation is catalyzed by HRP, generating blue coloration. This reaction is then stopped by addition of Stop Solution completing any color change from blue to yellow. Signal is generated proportionally to the amount of bound analyte and the intensity is measured at 450 nm. Optionally, instead of the endpoint reading, development of TMB can be recorded kinetically at 600 nm.

  • Notes

    CRP displays several functions associated with host defense: it promotes agglutination, bacterial capsular swelling, phagocytosis and complement fixation through its calcium-dependent binding to phosphorylcholine. CRP can interact with DNA and histones and it may scavenge nuclear material released from damaged circulating cells. CRP is secreted; it forms a homopentamer pentaxin (or pentraxin) which have a discoid arrangement of 5 non-covalently bound subunits. CRP binds 2 calcium ions per subunit. The concentration of CRP in plasma increases greatly during acute phase response to tissue injury, infection or other inflammatory stimuli. It is induced by IL1/interleukin-1 and IL6//interleukin-6.

  • Tested applications
    Suitable for: Sandwich ELISAmore details
  • Platform



Our Abpromise guarantee covers the use of ab181416 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
Sandwich ELISA Use at an assay dependent concentration.


  • ELISA Protocol Summary
  • Background-subtracted data values (mean +/- SD, n=2) are graphed.

  • Background subtracted data values (mean +/- SD, n=2) are graphed.

  • 10,000X diluted sera from 10 apparently healthy male donors were measured using this kit. Interpolated data values corrected for sample dilution are graphed in ng of CRP per mL of serum (mean +/- SD, n=2). Nine out of ten individual Human sera tested within or at reported Human serum range (< 5,000 ng/mL, dotted line). The mean of CRP concentration of these nine individual sera was determined to be 2,240 ng/mL with a range of 559 – 5,285 ng/mL. Note that one individual Human serum sample (donor # 2) tested substantially higher, 11,737 ng/mL.

  • Background subtracted data values of two serum dilutions (as indicated in parenthesis) are graphed (mean +/- SD, n=2).

  • The concentrations of CRP were interpolated from data values shown above using the CRP standard curve, corrected for sample dilution, and graphed in ng of CRP per mL of serum. As expected, note that the CRP serum concentrations are increased in RA patients.



This product has been referenced in:
  • Mentoor I  et al. Metabolic syndrome and body shape predict differences in health parameters in farm working women. BMC Public Health 18:453 (2018). ELISA ; Human . Read more (PubMed: 29618342) »
  • Cartwright M  et al. A broad-spectrum infection diagnostic that detects pathogen-associated molecular patterns (PAMPs) in whole blood. EBioMedicine N/A:N/A (2016). Sandwich ELISA ; Human . Read more (PubMed: 27333027) »
See all 3 Publications for this product

Customer reviews and Q&As

1-3 of 3 Q&A


The lab has done some further testing with diluents and I wanted to update you.

We can confirm that the 1X Wash buffer can be used to pre-dilute the biological sample 500 X. Another possibility is to use a mixture of 1X Wash Buffer and Sample Diluent NS for the pre-dilutions. The final dilution (that is added to the plate) should be made always in Sample diluent NS.

Please let me know if you have any further questions!

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We do not have an in-house ELISA protocol for detection of CRP in dried blood spots. We did however receive a positive review of our CRP ELISA ab181416 from a customer who used it with DBS samples. Here is a link to the review, in case you have not already seen it.


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I have confirmed with the lab and most of our C Reactive Protein antibodies, except C3 and C4, react with both monomer and pentamer form of CRP. (As our clones C3 and C4 do not recognize CRP in the absence of Ca2+ ions, we suggest that they could not recognize CRP monomer, but we have never experimentally tested this.)

ab10026, Anti-C Reactive Protein antibody [C1]

ab136176, Anti-C Reactive Protein antibody [C2]

ab8279, Anti-C Reactive Protein antibody [C5]

ab24462, Anti-C Reactive Protein antibody [C6] (HRP)

As pair I can recommend ab24462 and ab8279 to recognize both, monomer and pentamer.

https://www.abcam.com/index.html?datasheet=24462 (or use the following: https://www.abcam.com/index.html?datasheet=24462).

https://www.abcam.com/index.html?datasheet=8279 (or use the following: https://www.abcam.com/index.html?datasheet=8279).

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