Date published: 2026-4-11

1-800-457-3801

SCBT Portrait Logo
Seach Input

CD81 Antibody (5A6): sc-23962

4.1(14)
Write a reviewAsk a question

Datasheets
  • CD81 Antibody (5A6) is a mouse monoclonal IgG1 κ, cited in 127 publications, provided at 200 µg/ml
  • raised against OCI-LY8 cells
  • Anti-CD81 Antibody (5A6) is recommended for detection of CD81 of mouse, rat and human origin by WB, IP, IF and FCM
  • Anti-CD81 Antibody (5A6) is available conjugated to agarose for IP; HRP for WB, IHC(P) and ELISA; and to either phycoerythrin or FITC for IF, IHC(P) and FCM
  • also available conjugated to Alexa Fluor® 488, Alexa Fluor® 546, Alexa Fluor® 594 or Alexa Fluor® 647 for WB (RGB), IF, IHC(P) and FCM, and for use with RGB fluorescent imaging systems, such as iBright™ FL1000, FluorChem™, Typhoon, Azure and other comparable systems
  • also available conjugated to Alexa Fluor® 680 or Alexa Fluor® 790 for WB (NIR), IF and FCM; for use with Near-Infrared (NIR) detection systems, such as LI-COR®Odyssey®, iBright™ FL1000, FluorChem™, Typhoon, Azure and other comparable systems
  • m-IgG Fc BP-HRP and m-IgG1 BP-HRP are the preferred secondary detection reagents for CD81 Antibody (5A6) for WB applications. These reagents are now offered in bundles with CD81 Antibody (5A6) (see ordering information below).
Gene Editing Promo Banner

QUICK LINKS

SEE ALSO...

CD81 Antibody (5A6) is a mouse monoclonal IgG1 kappa light chain antibody specifically designed to target CD81 protein, also known as TAPA-1, a prominent member of the tetraspanin family characterized by its four transmembrane domains. CD81 is widely expressed on cells of hematopoietic, neuroectodermal, and mesenchymal origin, where CD81 plays a vital role in cell growth, signal transduction, and the organization of membrane microdomains. CD81 undergoes essential post-translational modifications, including palmitoylation and glycosylation, which are crucial for proper localization, stability, and interactions with other membrane proteins such as CD37, CD53, CD19, CD21, and MHC class II antigens. Anti-CD81 antibody (5A6) was developed using the OCI-LY8 B lymphoma cell line, ensuring effective detection of CD81 in mouse, rat, and human species through applications like western blotting (WB), immunoprecipitation (IP), immunofluorescence (IF), and flow cytometry (FCM). Available in both conjugated forms, including horseradish peroxidase (HRP), phycoerythrin (PE), fluorescein isothiocyanate (FITC), and various Alexa Fluor® conjugates, and non-conjugated forms, CD81 monoclonal antibody (5A6) provides versatile options for diverse experimental needs. By targeting CD81, researchers can investigate critical processes such as immune cell activation, viral entry mechanisms, and complex signaling pathways that govern cellular functions. Post-translational modifications of CD81 are particularly important for understanding CD81′s role in pathological conditions like cancer metastasis and immune disorders, making anti-CD81 antibody (5A6) an essential tool for both basic and applied research.

For Research Use Only. Not Intended for Diagnostic or Therapeutic Use.

Alexa Fluor® is a trademark of Molecular Probes Inc., OR., USA

LI-COR® and Odyssey® are registered trademarks of LI-COR Biosciences

Ordering Information

Product NameCatalog #UNITPriceQtyFAVORITES

CD81 Antibody (5A6)

sc-23962
200 µg/ml
$322.00

CD81 Antibody (5A6): m-IgG Fc BP-HRP Bundle

sc-526643
200 µg Ab; 10 µg BP
$361.00

CD81 Antibody (5A6): m-IgG1 BP-HRP Bundle

sc-532016
200 µg Ab; 20 µg BP
$361.00

CD81 Antibody (5A6) AC

sc-23962 AC
500 µg/ml, 25% agarose
$424.00

CD81 Antibody (5A6) HRP

sc-23962 HRP
200 µg/ml
$322.00

CD81 Antibody (5A6) FITC

sc-23962 FITC
200 µg/ml
$336.00

CD81 Antibody (5A6) PE

sc-23962 PE
200 µg/ml
$349.00

CD81 Antibody (5A6) Alexa Fluor® 488

sc-23962 AF488
200 µg/ml
$364.00

CD81 Antibody (5A6) Alexa Fluor® 546

sc-23962 AF546
200 µg/ml
$364.00

CD81 Antibody (5A6) Alexa Fluor® 594

sc-23962 AF594
200 µg/ml
$364.00

CD81 Antibody (5A6) Alexa Fluor® 647

sc-23962 AF647
200 µg/ml
$364.00

CD81 Antibody (5A6) Alexa Fluor® 680

sc-23962 AF680
200 µg/ml
$364.00

CD81 Antibody (5A6) Alexa Fluor® 790

sc-23962 AF790
200 µg/ml
$364.00

What is the isoelectric point for CD-81 antibody?

Asked by: Sumita
Thank you for your question. We do not characterize the isoelectric point of our antibodies.
Answered by: BlakeJ
Date published: 2025-07-23

Hello, I have used the CD81 antibody for western blot at 1:1500 in 5% MILK on exosomes from human plasma. Do you know why I get two bands, one at 23 kDa and another one at 48 kDa? Many thanks Juliana

Asked by: Juliana Redondo
Thank you for your question. The expected molecular weight for CD81 is ~ 22-26 kDa. We have not tested this antibody specifically in human plasma, and have not observed a higher molecular weight signal at 48 kDa in the cell lines tested. CD81 has been reported to dimerize (PMID: 20375010) and that may be a consideration. We would also recommend including a secondary antibody control, where you omit the primary antibody from the incubation, to confirm if the higher molecular weight band might be due to non-specific binding of the secondary antibody alone.
Answered by: Technical Support
Date published: 2017-10-16

Hi, I have used this antibody at 1:100 concentration on a western blot (10% SDS-PAGE gel) loading some exosomal protein. Could you explain please why I get not only the 26 kDa band, but also a band at about 50 kDa? Thank you.

Asked by: VivSal
Thank you for your question. We have not tested this antibody on exosomal protein, or observed a 50 kDa band in Western blot. We would recommend including a secondary antibody control (omit primary antibody) to identify if the 50 kDa band may be a result of non-specific binding of the secondary antibody alone. It could also be your secondary antibody binding to heavy chain IgG in your samples. Below is a link to our recommended protocol for Western blotting. Please contact our Technical Service Department if for additional support with troubleshooting the antibody. https://www.scbt.com/scbt/resources/protocols/western-immuno-blotting
Answered by: Technical Support
Date published: 2017-10-16

I have tried using this antibody on a western blot (after running an SDS-PAGE gel) with a homemade K562 lysate as control and did not get a signal at 1:100 dilution. I tried it 3 times previously on other cell lines at 1:200 w/no success. Any suggestions?

Asked by: Tali
Thank you for your question. If you have no signal, we would recommend verifying that your anti-mouse secondary is working well. We would also recommend including a loading control antibody (e.g., Actin or GAPDH) to ensure that your transfer conditions are good, as well as your signal detection conditions (e.g., chemiluminescence or other). We have successfully used this antibody for WB at a dilution of 1:200, loading 50 µg of K-562 whole cell lysate. A link to our complete recommended protocol is provided below. If you continue to have negative results, please contact our Technical Service Department so we can provide further troubleshooting support. Santa Cruz Biotechnology does warranty our antibodies for one year from the date of purchase. If we are unable to successfully troubleshoot your application we will send you a replacement antibody free of charge, or issue a credit or refund if that is not possible https://www.scbt.com/scbt/resources/protocols/western-immuno-blotting .
Answered by: Technical Support
Date published: 2017-04-26

What concentration would you recommend using SC-20048 at, to detect a protein in paraffin-embedded human tissue? We have used 1:1000 successfully for western blots. Please can you reply at your earliest convenience.

Asked by: Deborah Goberdhan
Thank you for your question! We recommend a starting dilution of 1:50 for IHC on paraffin embedded tissue sections. This is a starting dilution, so it is possible that you can use it much more diluted! We also recommend performing an antigen retrieval step, ideally sodium citrate with heat. You can find our recommended protocol here: https://www.scbt.com/scbt/resources/protocols/immunoperoxidase-staining If you have any further questions, please contact our European Technical Service team. You can reach them by phone at Toll Free: +49 6221 4503 0, by email at: europe@scbt.com or by live chat directly on our website, www.scbt.com
Answered by: Tech Service
Date published: 2017-02-22

1, What concentration do you recommend using SC-23962 on paraffin embedded human tissue sections? We have this antibody, so would like to try. ; 2. Do you think that SC-23962 FITC would work better and at what conc. for same application, ie IHC(P)?

Asked by: Deborah Goberdhan
Thank you for your question! We recommend a starting dilution of 1:50 for IHC on paraffin embedded tissue sections. We do recommend performing an antigen retrieval step. You can find our recommended protocol here: https://www.scbt.com/scbt/resources/protocols/immunoperoxidase-staining You can use the FITC conjugated form, although we do not generally use FITC conjugated antibodies for IHC in house, so I do not have test results for this. If you wish to try it, I would stick with the 1:50 starting dilution as well. If you have any further questions, please contact our European Technical Service team. You can reach them by phone at Toll Free: +49 6221 4503 0, by email at: europe@scbt.com or by live chat directly on our website, www.scbt.com
Answered by: Tech Service
Date published: 2017-02-22

Can I use this antibody for staining of mouse tissue, since it is a mouse antibody?

Asked by: Anna99
Yes. CD81 Antibody (5A6): sc-23962 is available conjugated to either phycoerythrin (sc-23962 PE) or fluoroscein (sc-23962 FITC), 200 µg/ml, for IF, IHC(P) and FCM.
Answered by: Tech Service 5
Date published: 2017-01-05
  • y_2026, m_4, d_9, h_7CST
  • bvseo_bulk, prod_bvqa, vn_bulk_3.0.43
  • cp_1, bvpage1
  • co_hasquestionsanswers, tq_7
  • loc_en_US, sid_23962, prod, sort_[SortEntry(order=LAST_APPROVED_ANSWER_SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_scbt
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getContent, 95ms
  • QUESTIONS, PRODUCT
Rated 4 out of 5 by from Great antibodyI request a sample of the antibody and it worked well!
Date published: 2023-07-31
Rated 4 out of 5 by from buon funzionamentoHo effettuato un solo esperimento per verificare la reattività nel cane e ha funzionato
Date published: 2023-07-14
Rated 1 out of 5 by from WBでバンドが検出できませんでした。エクソソームサンプルでCD81のバンドが全く検出できませんでした。同じサンプルで他のCD81抗体を使うとCD81を検出できたのでサンプルは問題ないと考えています。
Date published: 2021-09-09
Rated 2 out of 5 by from No band in Western blotI cannot see any band in Western blot after a nice transfer (all MW completely transfered; blotting using 1:200 of this antibody and 2nd antibody sc-516102 at 1:1000) of exosomes isolated by ultracentrifugation and further separated by density centrifugation. Perhaps I have low concentration of exosomes, but I expected to get at least a faint band.
Date published: 2021-05-25
Rated 5 out of 5 by from Works well in western blotThe antibody detected CD81 in Mesenchymal stem cells at the expected molecular size.
Date published: 2020-09-18
Rated 5 out of 5 by from Tested on HFFF by FACSThis antibody was tested on HFFF cells by FACS and shown a very strong signal, even at dilution 1:100
Date published: 2018-11-19
Rated 5 out of 5 by from Excellent antibody for ICC stainingThis antibody is gorgeous for ICC staining, please see the attached confocal image. Highly recommended. I tried 1:50 dilution for the first time, and you may further dilute it to 1:100 or even 1:200 to decrease the background a little bit, and it should work even better. I feel the overall quality of SCBT antibodies is getting much better,
Date published: 2018-11-08
Rated 5 out of 5 by from likeMembrane localization observed by Immunofluorescence staining of methanol-fixed embedded HeLa cells, also good for staining.
Date published: 2017-05-07
  • y_2026, m_4, d_9, h_7
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.43
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_14
  • loc_en_US, sid_23962, prod, sort_[SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_scbt
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getReviews, 18ms
  • REVIEWS, PRODUCT
CD81 Antibody (5A6) is rated 4.1 out of 5 by 14.
  • y_2026, m_4, d_9, h_7
  • bvseo_bulk, prod_bvrr, vn_bulk_3.0.43
  • cp_1, bvpage1
  • co_hasreviews, tv_0, tr_14
  • loc_en_US, sid_23962, prod, sort_[SortEntry(order=SUBMISSION_TIME, direction=DESCENDING)]
  • clientName_scbt
  • bvseo_sdk, java_sdk, bvseo-4.0.0
  • CLOUD, getAggregateRating, 99ms
  • REVIEWS, PRODUCT