Hi everyone, I am new to this site and so I hope I am posting in the correct place. I am attempting to do a H2O replacement technique using a graded ethanol series (70%-->80%-->95%-->100%) on human soft tissue, intervertebral disc to be exact. The tissue is approx 1cm X 1cm X 1cm (for subsequent SEM CO2 drying and SEM imaging) and my question is this. How long do you all think I need to "soak" my tissue cube in each solution before moving onto the next? The literature is rather confusing and doesn't appear to have a hard suggestion. If it helps at all, it's going to be done at room temp. Thanks!