These instructions apply to the WellMed Citrate buffer, Heat-Induced Epitope
Retrieval (10x, Tween20).
- Intended Use
- Summary and explanation
- Reagents supplied
- Usage
- Warnings and precautions
- Storage and stability
- Microbiological state
- Supplied as
- Troubleshooting
- Reference
1: Intended Use
For In Vitro Diagnostic and Research Use. WellMed Citrate buffer is intended for use in
immunohistochemistry for heat-induced epitope retrieval.
2: Summary and explanation
WellMed Citrate buffer, is designed for use during heat-induced epitope retrieval (HIER) on formalinfixed paraffin-embedded tissue sections prior to antibody application. In immunohistochemistry (IHC),
protein cross-links are formed during formalin or other aldehyde fixation. These cross-links mask the
antigenic sites in tissue specimens and results in weak or false negative staining in immunohistochemical
detection of proteins. The use of this citrate buffer in combination with heat ensures that the
antigenicity of proteins modified, thus enhancing staining intensity of antibodies. For the recommended
pre-treatment technique, please refer to the individual antibody’s instructions for use. This buffer is a
10x concentrate solution and must be diluted 1:10 with deionized water before using. The final readyto-use solution should have a pH of 6.0 ± 0.3. The buffer can be used for a maximum of three runs
within five days after dilution
3: Availability
| Catalog Number: | Contents: | Volume: |
| HIER1000CC | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20) clear | 1000 ml |
| HIER1000CR | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20), Red color | 1000 ml |
| HIER500CC | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20) clear | 500 ml |
| HIER500CR | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20), Red color | 500 ml |
| HIER250CC | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20) clear | 250 ml |
| HIER250CR | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20), Red color | 250 ml |
| HIER100CC | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20) clear | 100 ml |
| HIER100CR | Citrate buffer, Heat-Induced Epitope Retrieval (10x, Tween20), Red color | 100 ml |
4: Recommended usage
Before use dilute 1:10 with deionized water. The final ready-to-use solution should have a pH of 6.0 ±
0.3. Protocol:
- Deparaffinize and rehydrate the tissue slides.
- Fill the PT Module tank with 150 ml of citrate buffer and 1,350 ml of deionized water, to obtain
1,500 ml of ready-to-use solution (1:10 dilution). - Pre-heat the PT Module until temperature reaches 65°C and place the formalin-fixed slides in
slide racks into the PT Module tank. - Heat the citrate buffer and slides to 98°C and incubate for 20 minutes.
- Cool slides in the PT Module to 65°C.
- Remove slides and cool to room temperature for at least 5 minutes in a PBS or TBS based buffer.
- Continue with staining according to IHC protocol.
Note: Alternative heating sources, such as a microwave or a pressure cooker, can be used to replace thePT Module tank. The optimal incubation time for these heating sources should be determined by authorised personnel / researchers.
5: Warnings and precautions
Refer to SDS.
6: Storage
Store at room temperature. Do not use after the expiration date.
7: Microbiological state
Product(s) not sterile.
8: Supplied as
10x concentrate solution, in clear and red.
9: Troubleshooting
Please contact WellMed by phone or by email.
10: Reference
[1] Morgan JM, Navabi H, Schmid KW, Jasani B (1994) Possible role of tissue-bound calcium ions in
citrate-mediated high-temperature antigen retrieval. J Pathol. 174(4):301-7.
[2] Hoffman, E. A., Frey, B. L., Smith, L. M., & Auble, D. T. (2015). Formaldehyde Crosslinking: A Tool for
the Study of Chromatin Complexes. Journal of Biological Chemistry, 290(44), 26404–26411.