The microscopy field is moving away from blue dyes. This is because red light, used to excited far red and deep red fluorophores, is less damaging to live cells than near UV light which is used to excite blue fluorophores.
On top of that, red light penetrates deeper into thick samples.
So as the trend in microscopy is to move to thicker samples and use more live samples, far red and deep red fluorophores are becoming more attractive.
Here is an article describing 3 new fluorescent protein in the far red to deep red range. One can excite them with 640 nm or a 685 nm lasers or LEDs.
4 thoughts on “Deep red fluorescent proteins”
I would just add that though these are really cool fluorochromes, they need binding of Biverdin in order to be active. That is no issue in vivo, but may cause trouble in some tissue culture cell lines.
Great Jan! Thanks for the info! 😀
Small erratum, I meant Biliverdin of course :D. And here is one provider I found https://www.aablocks.com/prod/114-25-0