Dear Laetitia,

That depends on what you want to conjugate and which method you're planning to use.

Conjugating dyes, e.g. for fluorescence microscopy, is quite straight forward (buffer exchange into an amine free buffer, add reactive dye, mix, incubate, purify by gel filtration). Conjugating payloads is more sophisticated, esp. if you want them to be released inside a target cell later.

If there should be stabilizers like BSA in your antibody prep or the antibody is not pure (hybridoma supernatant, ascites, ...), purificiation is highly recommended, otherwise you'll waste a lot of reagents (and money) and might have high background.

For an overview of options and possibilities, please take a look at our Linkerology brochure at https://www.iris-biotech.de/linkerology.

If you have special questions, please post here.

Dear Wilfgang,

I'm planning to conjugate antibodies (trastuzumab, nivolaumab) with DOTA, DFO, NOTA

Thanks for the link

Dear Laetitia,

for DOTA, PEG (or poly amino-acid) spacered TFP-esters might be the most straightforward approach. Maleimides are tricky here, as you need to partially reduce the antibodies to get free sulfhydryls.

Same for NOTA, but ready to use linker/ligands might be difficult to procure, as it might be the case for DFO. PubChem and SciFinder might be helpful to locate them, at least to retrieve their CAS-Numbers.