• Product name
    Human C Reactive Protein ELISA Kit (PTX1)
    See all C Reactive Protein kits
  • Detection method
  • Precision
    Sample n Mean SD CV%
    Overall 4%
    Sample n Mean SD CV%
    Overall 11.3%
  • Sample type
    Cell culture supernatant, Saliva, Milk, Urine, Serum, Plasma, Cerebral Spinal Fluid
  • Assay type
    Sandwich (quantitative)
  • Sensitivity
    = 0.2 ng/ml
  • Range
    0.25 ng/ml - 16 ng/ml
  • Recovery

    96 %

  • Assay time
    4h 00m
  • Assay duration
    Multiple steps standard assay
  • Species reactivity
    Reacts with: Human
  • Product overview

    Abcam’s C Reactive Protein (PTX1) Human in vitro ELISA (Enzyme-Linked Immunosorbent Assay) kit is designed for the quantitative measurement of C Reactive Protein concentrations in Human plasma, serum, saliva, milk, urine and cell culture supernatants.

    A C Reactive Protein specific antibody has been precoated onto 96-well plates and blocked. Standards or test samples are added to the wells and subsequently a C Reactive Protein specific biotinylated detection antibody is added and then followed by washing with wash buffer. Streptavidin-Peroxidase Conjugate is added and unbound conjugates are washed away with wash buffer. TMB is then used to visualize Streptavidin-Peroxidase enzymatic reaction. TMB is catalyzed by Streptavidin-Peroxidase to produce a blue color product that changes into yellow after adding acidic stop solution. The density of yellow coloration is directly proportional to the amount of C Reactive Protein captured in plate.

    Get results in 90 minutes with Human C Reactive Protein ELISA Kit (ab181416) from our SimpleStep ELISA® range.

  • Tested applications
    Suitable for: Sandwich ELISAmore details
  • Platform


Associated products


Our Abpromise guarantee covers the use of ab108826 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.


  • Representative Standard Curve using ab108826



This product has been referenced in:
  • Strøm Halden TA  et al. Short-term efficacy and safety of sitagliptin treatment in long-term stable renal recipients with new-onset diabetes after transplantation. Nephrol Dial Transplant 29:926-33 (2014). Read more (PubMed: 24452849) »
See 1 Publication for this product

Customer reviews and Q&As

1-4 of 4 Abreviews or Q&A


Thank you for your reply.

1. Your software may have a way to adjust the correction wavelength, or you can run it without the correction factor. The 570 wave length is subtracted to reduce the background noise and lower the OD. If you are unable to do so on the reader/software, then they can assume the blank (0 pt of the standard curve) represents the background noise and subtract the average of that OD from the OD of each well of the plate.

2. The kit comes in a box with the following components and described on the datasheet. It will arrive with an ice pack but please check the storage details to ensure the items are stored correctly once they arrive:ion

C Reactive Protein Microplate (12 x 8 well strips) 96 wells 4°C

C Reactive Protein Standard 1 vial 4°C

10X Diluent M Concentrate 30 mL 4°C

Biotinylated Human C Reactive Protein Antibody 1 vial -20°C

100X Streptavidin-Peroxidase Conjugate

(SP Conjugate) 80 μL -20°C

Chromogen Substrate 8 mL 4°C

Stop Solution 12 mL 4°C

20X Wash Buffer Concentrate 2 x 30 mL 4°C

Sealing Tapes 3 N/A

3. Diluent M: Once diluted, diluent M is stable for up to 1 month at 4oC so we recommend to use it within 1 month. If you don't want to use up all the 1X diluent M within one month, you can take out just some of the 10X stock solution to prepare. Please read through the protocol book carefully for storage instructions for kit components once they are reconstituted as this may be different from above.

4. For uriine samples: Collect urine using sample tube. Centrifuge samples at 800 x g for 10 minutes and assay. Samples can be stored at -20°C or below for up to 3 months. Avoid repeated freeze-thaw cycles. However, as it is a sample that needs to be run undiluted, we do not provide linearity data for it.

I hope this will be helpful. If you have any further questions, please do not hesitate to contact us.

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I checked the details and can confirm that C Reactive Protein (PTX1) Human ELISA Kit ab108826 has been tested and covered by the guarantee for use in urine samples. Our apologies for any confusion.

I was not able to find any literature to confirm the level of C Reactive Protein (PTX1) in urine. I contacted the laboratories in this case and they said they tested multiple samples with this kit and observed a great difference between samples (example: female vs male). The average value is around 0.4 ng/ml but they observed much lower and much higher values as well. They used samples with endogenous C Reactive Protein.

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Thank you for your enquiry regarding these kits.

I would suggest reading through the Protocol Booklets for each of these kits provided on the product datasheets. These documents contain specific information about the sample types, sample preparations, protocol, instruments and equipment required for the assays. Whole blood samples are not used to test these kits mainly serum or plasma instead.

ab46044: https://www.abcam.com/high-sensitivity-il6-human-elisa-kit-2-x-96-well-plates-ab46044.html

ab100642: https://www.abcam.com/ps/products/100/ab100642/documents/ab100642-Soluble-TNF-Receptor-I-Human-ELISA-Kit-ab100642-protocol-plain.pdf

ab100643: https://www.abcam.com/ps/products/100/ab100643/documents/ab100643-Soluble-TNF-Receptor-II-Human-ELISA-Kit-ab100643-protocol-plain.pdf

ab108826: https://www.abcam.com/ps/products/108/ab108826/documents/ab108826%20C%20Reactive%20Protein%20Human%20ELISA_v2%20(Website).pdf

As you are aware our Abpromise indicates, in the event that a product is not functioning in the applications/species cited on the product data sheet (and the problem has been reported within 6 months of purchase) we will happily offer a credit note/refund to the value of the product purchased. Therefore please advsie yiur customer to use teh product as soon as possible after purchase to make sure that we can provide the best technical support within the guarantee period.

The specific storage instructions can also be found on the product datasheets. It is not clear if the customer would like to use these products in serum from normal, or drug treated or diseased (pathological conditions) individuals. We would suggest optimizing the assay and using standards.

Let me know if you haveany further questions.

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Thank you for your enquiry. I can confirm that both these kits ab46042 and ab108826 should be suitable for use with saliva samples. I can confirm that  kit ab108826 has been tested on saliva samples,  We suggest to use saliva samples at 1x (no dilution) for this kit. We would suggest ab46042 should be suitable for saliva samples. However, this has not been specifically tested. Therefore, we are able to offer a discount for this kit in return for agreement to submit an Abreview with the data. I am currently waiting to hear from my colleagues how much of a discount we can offer and will be in touch with you as soon as possible. I hope this will be helpful. If you have any further questions, please do let me know. I will be in touch again regarding ab46052.  

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