One for All: the Universal Buffer
We proudly present patent pending R-Universal (R stands for Retriever) buffer for antigen unmasking/epitope recovery on formalin-fixed, paraffin embedded sections. Being specifically developed for the 2100 Retriever, it was thoroughly tested in pathology research labs in the UK, and now is available for all users of Retriever and other researchers who work with routine tissue material. Moreover, the quality of recovery greatly depends on the quality of fixation and processing, in particular – length of fixation, quality of washing from the fixative, and the temperature of paraffin used. When one performs large series of stainings on collections from archives, formed over some time, there is a risk of differences in efficacy of retrieval.
An excellent solution for epitope recovery has been achieved with the 2100 Retiever, and the new R-Universal buffer. The specially designed program of heating-cooling in Retriever was from the very beginning created for the best results in reshaping the denatured epitopes (allowing their proper refolding). But the new Retrieval buffer combines the removal of formaldehyde-formed protein cross-links with the removal of Ca++. And no toxic agent, such as Citraconic anhydride, is used.
As a result, you can perform recovery of practically all epitopes in one buffer.
Which allows you:
- treat all sections in one buffer, so no buffer is wasted, when you have to treat several small series of sections in different buffers
- use one buffer not only instead of different High, Low, etc buffers, but also to recover epitopes that normally require protease (Trypsin, Proteinase K) treatment
- use practically any antibody previously not tested (or unsuccessfully tested) on formalin-fixed sections.
- perform IF staining formalin-fixed on sections, as autofluorescence, even produced by excess of unwashed formaldehyde, will go away during the section processing
- perform multicolour IF on sections, even when using antibodies that normally require epitope recovery in different buffers
- get the strongest staining, superior to any other methods for epitope recovery. You will have more confidence that what you see as negative – is indeed negative, and not a result of poor epitope recovery
In other words, you may have all the conveniences of IHC on frozen sections, while having excellent tissue morphology of formalin-fixed.
On the image you see staining with three standard antibodies from Dako, to Cyclin D1, Lambda chain, and GFAP. Each of these require individual buffer (Low, High, or protease treatment) for a proper epitope recovery to avoid a non-specific staining produced by the respective mAb. Left panel shows staining on sections processed with recommended buffer, on the ladt panel – with R-universal buffer. Please not a much better discrimination between positive and negative cells (and stronger staining) for CyclinD1 and Lambda chain.
- T.Mellows, S.Litvinov, G.Thomas, A novel universal epitope recovery buffer for formalin-fixed sections: (in preparation)
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