10x Citrate Buffer pH 6.0 (ab64214)

I need to develop double IHC analysis on formalin-fixed paraffin-embedded (FFPE) tissue sections of human tumors specimens, and after we have to do laser capture microdissection of positive cells.   I already have two primary antibodies directed against CD44 (produced in mouse) and against ALDH1 (produced in rabbit).   I'm looking for double staining kit (or all of the individual components which analysis needs) with alcohol insoluble chromogens because after IHC and before laser cature microdissection I have to dehydrate the slides.   Thank you for your time and consideration.

ANSWER:

Thank you for contacting us.

We do not currently offer double staining IHC kits. Your staining conditions are challenging as, of the two common HRP chromogens, only DAB is alcohol insoluable. While of the common AP chromagens, only BCIP/NBT is insoluable. This means that to do double labeling you will have to do a sequential stain first using one detection system and then with the other.

I have collected a list, with links, of the reagents which you would need for this type of staining.

1) After de-parrafinizing and re-hydrating the samples, perform an antigen retrieval step treating with Cirate buffer pH6.0,http://www.abcam.com/10x-Citrate-Buffer-pH-6-0-ab64214.html, in the microwave or pressure cooker. After performing the antigen retrieval rinse in cold tap water for 10 minutes.

2) Rinse slides in TBST,http://www.abcam.com/20x-TBS-T-with-Tween-20-ab64250.html.

3) Performing a blocking step using protein block,http://www.abcam.com/Protein-Block-ab64226.html.

4) Incubate sections with your first primary antibody, for clarity I will assume the CD44 antibody, raised in mouse.

5) Wash with TBST.

6) Block endogenous peroxidases using aHydrogen Peroxide Blocking Reagent,http://www.abcam.com/Hydrogen-Peroxide-Blocking-Reagent-ab94666.html.

7) Incubate your tissue with a biotinylated secondary antibody, in this instance anti-Mouse IgG,http://www.abcam.com/Biotinylated-Goat-anti-Mouse-IgG-H-L-Ready-to-Use-ab64255.html.

8) Wash with TBST.

9) Detect your first antibody usingStreptavidin Peroxidase (Ready to Use)http://www.abcam.com/Streptavidin-Peroxidase-Ready-to-Use-ab64269.html. Note that this does not containa serum or BSA solution as diluent. Serum may contain biotin therefore competing Streptavidin binding with biotinylated secondary antibody, therefore reducing binding activity.

10) Apply your chromogen, DABsubtrate,http://www.abcam.com/DAB-Substrate-Kit-ab64238.html.

11) Wash with TBST.

12)Performing a second blocking step using protein block,http://www.abcam.com/Protein-Block-ab64226.html.

13)Wash with TBST.

14)Incubate sections with the your second primary antibody, this time ALDH1, raised in rabbit.

15)Wash with TBST.

16)Incubate your tissue with a biotinylated secondary antibody, in this instance anti-Rabbit IgG,http://www.abcam.com/Biotinylated-Goat-Anti-Rabbit-IgG-H-L-Ready-to-use-ab64256.html

17)Wash with TBST.

18)Detect your first antibody usingStreptavidin Alkaline Phosphatase (Ready to Use)http://www.abcam.com/Streptavidin-Alkaline-Phosphatase-Ready-to-Use-ab64268.html.

19) Apply your second chromogenAlkaline Phosphatase chromogen (BCIP/NBT) - Ready to Use,http://www.abcam.com/Alkaline-Phosphatase-chromogen-BCIP-NBT-Ready-to-Use-ab7468.html.

18) Wash with TBST, counterstain if desired.


I hope this information is helpful to you. Please do not hesitate to contact us if you need any more advice or information.

ab64214

What is the concentration of the citrate in the buffer?

ANSWER:

Thank you for your recent telephone enquiry.

I can confirm that the concentration of citrate in the buffer is 30 mM.

I hope this will be helpful to you. Should you have any further questions, please do not hesitate to contact us. Good luck with your research!

How would I make a 0.1M solution of this? I am horrible with dilutions and I'm having a hard time figuring this one out...Any help would be greatly appreciated!　I'm sorry, I think I actually need 10mM. This is for antigen retrieval step in IHC-P (formalin fixed).

ANSWER:

Thank you for your enquiry.

Unfortunately, the concentration of 10 X citrate buffer is proprietary and can not be released. However, we can suggest that you make a ten times dilution of the buffer for the antigen retrieval. Simple take 1ml of this solution and dilute with 9ml of deionized water (DW).

I hope this information helps. If there is anything else that I can help you with, please do not hesitate to contact me.