• Product name
    Calcium Assay Kit (Colorimetric)
    See all Calcium kits
  • Sample type
    Urine, Serum, Plasma, Other biological fluids, Tissue Extracts, Cell Lysate, Cell culture media
  • Assay type
  • Sensitivity
    > 0.1 mM
  • Range
    0.1 mM - 25 mM
  • Assay time
    0h 20m
  • Species reactivity
    Reacts with: Cat, Human, Mammals
  • Product overview

    Calcium Assay Kit (Colorimetric) (ab102505) provides a simple assay to determine calcium concentration within the physiological range of 0.4 – 100 mg/dL (0.1 – 25 mM). A chromogenic complex is formed between calcium ions and 0-cresolphthalein and measured at OD = 575 nm.

    This product detects free calcium ions only.

    Visit our FAQs page for tips and troubleshooting.

  • Notes

    Calcium is essential for all living organisms, where Ca2+ sequestration and release into and out of the cytoplasm functions as a signal for many cellular processes. 99% of calcium is found in bones and teeth with the remaining 1% found in the blood and soft tissue. Serum calcium levels are tightly controlled (8.4-11.4 mg/dL) and any variation outside this range can have serious effects. Calcium plays a role in mediating the constriction and relaxation of blood vessels, nerve impulse transmission, muscle contraction, and hormone secretion. Calcium ion channels control the migration of calcium ions across cell membranes, permitting the activation and inhibition of a wide variety of enzymes. Causes of low calcium levels include chronic kidney failure, vitamin D deficiency, and low blood magnesium levels that can occur in severe alcoholism.



  • Ca2+ concentration (millimolar) in various biologicals. Shown bars are average of values from dilutions neat to 1:8.

  • Example of standard curve obtained using ab102505



This product has been referenced in:
  • Nada AM & Shaheen DA Cholecalciferol improves glycemic control in type 2 diabetic patients: a 6-month prospective interventional study. Ther Clin Risk Manag 13:813-820 (2017). Read more (PubMed: 28740392) »
  • Koskela A  et al. Perfluoroalkyl substances in human bone: concentrations in bones and effects on bone cell differentiation. Sci Rep 7:6841 (2017). Functional Studies ; Human . Read more (PubMed: 28754927) »

See all 12 Publications for this product

Customer reviews and Q&As

Thank you for getting in touch. I am happy to provide answers to your questions:

1. According to the website the linear range of detection for this kit is between 0.1-25 mM? What about higher that?

It is possible to detect higher amou...

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Based on the laboratories experience with the ab102505Calcium Detection Kit, for human serum samples they have either added 10 ul directly or did a 1:2 dilution with assay buffer and added 10 ul to the reaction well.

Please note that this...

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Excellent Excellent 5/5 (Ease of Use)
I used the calcium detection buffer to test calcium concentration in Arabidopsis, it works well.

Abcam user community

Verified customer

Submitted Jul 21 2015

I was not able to obtain the composition of the two buffers (they are considered proprietary) but the laboratory has informed me that the buffer in the calcium assay is unlikely to be compatible with the ALP activity assay.

That said, you migh...

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serum calcium in dogs

Good Good 4/5 (Ease of Use)
Used this product in a standard blank ELISA plate format. Programmed a DiaSorin ETI-MAX to run the procedure. Product worked as specified in dogs with no problems. Have found the curve to be very stable run-to-run.

Overall inter/intra assay precision is 5.9% and 3.6% respectively.

Randy Ringold

Verified customer

Submitted Sep 08 2014

Serum calcium in cats

Good Good 4/5 (Ease of Use)
Used to product to test for serum calciums in cats. Programmed a DiaSorin ETI-MAX to run the procedure on standard ELISA plates. Product performed as specified with an inter/intra assay precision of 4.9% and 3.2% respectively.

Randy Ringold

Verified customer

Submitted Sep 03 2014

Ich habe nun einen Bestätigung von Labor: Der Farbstoff 0-cresolphthalein emittiert zwischen 540-600nm. Die spektralen Eigenschaften von 0-cresolphthalein hängen stark vom pH-Wert und der Bindung an Metallionen wie Calcium ab. Da f&...

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The blood vessel walls (largely Endothelial cells) samples can be homogenized in the assay buffer (contains detergent to help lyse cells) and then spun down to prepare a lysate. Several volumes of this lysate must be tested to make sure the r...

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Thank you for contacting us.

The sample type of kit as mentioned on datasheet lists tissue extracts, this means the kit is suitable for any kind of tissue sections however you may need to optimize expermental conditions.

I hope this ...

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Thank you for contacting us.

This kit can be used to detect the Calcium with rat serum and cell lysates/supernatant.

To know the price please contact our Indian distributor Allied Scientific.

Allied Scientific Products
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