Hi!!
We've been using this product for quite a while now for our whole embryo in situs hybridization with mice embryos:
https://www.sigmaaldrich.com/ES/es/product/roche/11383213001
The thing is, it progressively creates crystals at the bottom of the bottle, making it unable to pipette and use properly. Has anyone encountered this problem? Is this just what's supposed to happen? We store it at -20ºC
thank you very much in advance