Osteopontin ELISA Kit


Human osteopontin ELISA kit is a reliable quantitative method for measuring osteopontin (OPN) in human cell culture media, plasma and urine samples. This assay has a sensitivity detection limit of 3.33 ng/ml.


Osteopontin (OPN) which is also known as urinary stone protein, is a highly acidic calcium-binding glycosylated phosphoprotein that can be secreted by many cell types, such as kidney tubule cells, activated T cells, osteoblasts, vascular smooth muscle cells and macrophages. It has a molecular weight that can range from 66kDa to 44kDa depending on its phosphorylation and glycosylation states. It contains an Arg-Gly-Asp (RGD) amino acid sequence, this motif is also present in vitronectin, fibronectin and many extra cellular proteins which have the ability to bind members of the integrin family of cell surface receptors. It can be also present in a number of different molecular forms in vivo that can be due to phosphorylation, glycosylation, susceptibility to proteases, sulfation and differential RNA splicing.

Osteopontin is also susceptible to proteolytic fragmentation and there is suggestions that this process may have physiologic importance, for example, a study demonstrated that thrombin treatment can enhance OPN cell adhesive activity, implying that cleavage of human osteopontin by thrombin can lead to exposing a cryptic adhesive sequence. We are highly recommend serum samples are not used for the measurement of OPN because of their limited stability.


All reagents supplied need to be stored at 2 °C – 8 °C, unopened reagents will retain reactivity until expiration date. Do not use reagents beyond this date.

  • Pre-Coated Microplate: Wells bound with osteopontin antigen (O-17) rabbit IgG affinity purify.
  • Labelled Antibody (30x Concentrated): Consisting of HRP conjugated to anti-osteopontin (10A16) mouse IgG.
  • Standards: Concentrations 0, 5, 10, 20, 40, 80, 160, 320.0 ng/ml.
  • Antibody Labelling Solution.
  • TMB Chromogen Solution.
  • Stop Solution.
  • Wash buffer (40x Concentrated).


The minimum sensitivity detection limit of osteopontin (OPN) using current osteopontin ELISA kit was approximately 3.33 ng/ml. The dynamic range for this assay is 5.0 – 320.0 ng/ml.


– Osteopontin (OPN): ELISA
– Recovery (Accuracy): 95.6 – 108.7%
– Intra Assay: 4.4 – 10.1%
– Inter Assay: 7.8 – 9.3%
– Specificity: Human-OPN (100%), Mouse-OPN (0.2%), Rat-OPN (<0.1%).
– Sensitivity: 3.33 ng/ml


  1. Phosphate is a specific signal for induction of osteopontin gene expression. Proc. Nat. Acad. Sci. (200) 97: 8352-8357. Beck, G. R.; Jr. Zerler, B. and Moran, E.
  2. Molecular cloning and sequencing of cDNA encoding urinary stone protein, which is identical to osteopontin. Biochem. Biophys. Res. Commun. (1992) 184: 859-864. Kohri, K., et al.
  3. Human bone sialoprotein: deduced protein sequence and chromosomal localization. J. Biol. Chem. (1990) 265: 2347-2351. Fisher, L. W.; McBride, O. W.; Termine, J. D. and Young, M. F.


  • Full Name: Osteopontin ELISA Kit
  • Reactivity: Human
  • Sample Type: Plasma (EDTA), Cell Culture Media, Urine
  • Sensitivity: 3.33 ng/ml



Your secretory IgA ELISA gave good results and I was also really impressed with how quickly we received it.

L. Johnston
PhD Student / University of Glasgow

It is refreshing to know that you have a technical team that is very knowledgeable. I have already recommended your company to other researchers in our department.

Dr. P. Anderson
Lecturer / University College London (UCL)

I am a first time user and found that your instruction manual was very easy to follow. The insulin ELISA assay performed well and I was happy with the results that were generated.

J. Thomas
Senior Technician / Addenbrooke’s Hospital

I carried out a pilot study comparing the performance of many ELISA assay's from different suppliers and found your kits to be one of the better performers. We observed good linearity and tight replicates.

Dr. C. Davies
Lead Scientists / AstraZeneca

You are my first point of contact when I am looking to purchase ELISA. You have such an easy and simple system, yet it is very effective.

A. Shaw
Purchasing / University of Oxford