Was the solution clear before you autoclaved it? Could be the glass flask used to mix it, or the glass bottle and cap, were not clean. I normally filter sterilize EDTA, the solution is always clear.

The color of 0.5M EDTA solution can be from colorless to slight yellow. See attachment.

High purity EDTA crystals "certified ACS" (Fisher) has always been perfectly clear for me when made into a solution.

 i always prepare it in the same bottle.  it was clear. everything were clear.  The first time I encountered such a thing . thank you your answers.

There was also a medium in autoclave. could it be mixed by vapor?

Hi Miray,

I am not sure of vapor. But did you let it stand in the autoclave for a long time (such as placing them in the autoclave and started autoclaving and come to get it after your class) this time?

For MS medium (a kind of plant tissue-culturing medium), some times some people will get slight yellowish color after autoclave. This problem has been discussed on RG, and some people suggested that this can be due to the medium stays too long in the autoclave, and components (such as carbohydrates) turn caramelized. But, I am not sure whether this also suit for the EDTA case.

EDTAyı her zaman filtre et 0.22

@miray sahinkaya

What is the purpose of autoclaving of EDTA?

May be glassware was clean and after autoclaving impurities on the glassware, the surface dissolves in the solution. Should be prepared with again