Anti-Chromogranin B 抗体 (ab12242)

Thank you for taking the time to complete our questionnaire and contact us. I am sorry to hear you have had difficulty obtaining satisfactory results from this antibody.

The details you have kindly provided will enable us to investigate this case for you and this is also helpful in our records for monitoring of quality. I would like to reassure you that this antibody is tested and covered by our guarantee for WB.


Reviewing this case, I would like to offer some suggestions to help optimise the results from ab12242.

1.) Chromogranin B is only predicted to be of the size of 78kDa. It is highly phosphorylated on multiple sites which affects its apparent molecular weight on a gel. The lab confirmed that they see this protein at a size of ca 110kDa on gels due to all the modifications.
On the image send to me there is a band at the right size (ca117kDa) that appears only in the secretory rat cells.

Therefore I believe this is a case of a high background and would like to offer the following recommendation for the optimization:

1.) I suggest to use proteinase inhibitors. Since all bands are smaller than the expected protein, it could be degradation products.

2.) I also recommend to run a no primary control to verify that the secondary alone is not producing any bands.

3.) Using BSA as blocking agent can lead to much better results with some antibodies. This has to be tested experimentally, since it is not known why some antibodies work better with BSA.

4.) I suggest to incubate the primary antibody over night at 4C. This ensures the most specific staining.

5.) If antibodies are used to concentrated they start binding un-specifically. I therefore suggest to further dilute the primary antibody.


In the event that a product is not functioning in the applications cited on the product data sheet (and the problem has been reported within 6 months of purchase), we will be pleased to provide a credit note, free of charge replacement or refund.

I hope this information is helpful, thank you for your cooperation. Should the suggestions not improve the results, please do not hesitate to contact me again with the further requested details.

Thank you for your email. We unfortunately do not have ab8205 anymore and we also do not have exactly same product in catalogue.  However we do have many "Chromogranin A" antibodies that are very well characterized. You may consider trying.  The catalogue number of few of these is; ab43844 ab45179 ab79276 ab80787 ab75939 These antibodies are characterized with rat samples and are fully guaranteed to work. I am sorry to hear that you had problem with ab12242 it should have worked in IHC-P. Have you contacted scientific support team and discussed the problem. Under the Abpromise scheme you could have received a free of charge replacement product. Click below for Abpromise guarantee; https://www.abcam.com/index.html?pageconfig=abpromise I hope this information will help for ordering these products. Should you have any question please do not hesitate to contact me.

Thank you for your enquiry and your interest in our products. Here is the protocol that was used to develop this antibody: Frozen pellets of PC12 pheochromocytoma cells were thawed (1 g wet weight/10 ml) in a buffer containing 20 mM Tris-HCl (pH 7.4), 10 mM EDTA, 5 mM 2-mercaptoethanol, and 0.1 mM PMSF at 4 C. The suspension was sonicated on ice using five 10-sec bursts at a setting of 5 with a Branson Sonifier 250 and centrifuged at 100,000 x g for 30 min at 4 C. The supernatant was adjusted to 0.1 M NaCl, boiled for 5 min, and centrifuged again at 100,000 x g for 30 min. The resulting supernatant was concentrated 10-fold using an Amicon Ultrafiltration Cell and a Diaflo YM 30 Ultrafilter (30,000 mol wt cut-off). The protein concentration for the resulting fraction was determined by the method of Lowry et al. using BSA as the standard. Supernatants were boiled in an equal volume of 2-fold electrophoresis sample buffer containing 2% SDS, 0.004% bromphenol blue, 20% glycerol, 4% beta-mercaptoethanol, and 0.12 M Tris-HCl, pH 6.7. Analysis was performed by SDS-PAGE on 10% or 12% gels followed by Western blotting with the antibody at a dilution of 1:100. We hope this information will be useful for you.

This product is sold as whole antiserum, not as purified antibody. In general, we estimate that the total Ig concentration in serum is approx. 10 mg/ml, and the specific antibody component is approx. 10% of this. I hope this helps.

Thank you for your enquiry. This product is whole, undiluted antiserum, so it is not in a storage buffer. To dilute for use, we recommend either PBS or a buffer/medium that is compatible with the user's assay system.