Cadmium chloride solubility - (Apr/08/2012 )

Dear All

I have a very weird story of cadmium chloride solubility. For the first time i prepared i remember it was highly soluble in PBS PH7.2. while i am trying to prepare another lot of cadmuium chloride, it is not soluble at all. It forms a white layer (gel like). Nevertheless,This substance is highly soluble in water

I use this substance in concentration of 25uM for inhibition of HIF in macrophages. Could anyone please explain to me why this is not soluble in PBS?

Thank you for your attention

Could be forming some sort of cadmium phosphate (though I can't find that in my merck index), which according to wikipedia is highly insoluble, if you can trust wikipedia.

Incidentally, my colleague was inhibiting HIF (hypoxia inducible factor) with cobalt chloride, not cadmium chloride.

Yes, heavy metal chlorides are very soluble, and they give an acidic pH in solution.

Heavy metal phosphates are highly insoluble, some more than others, and to make heavy metal toxicity tests (MIC) when working with non-acidophiles is usually necessary to use chelators to solubilize them. I'm working with uranium and as I rise from pH 2 it precipitates, no matter small quantity of phosphate is present (0.2 mM phosphate in my medium). Cd phosphate solubility is about ug/100mL.

If your reactive Cd chloride is not soluble in water anymore maybe it may have suffered some hydrolysis reaction like the zinc chloride. I don't know if this happen for Cd but the Zn choride reacts with the humidity in the air forming Zn oxychloride insoluble, leaving the reactive useless.