Tin (Sn) Identification - Microwave Digestion - ICP OES

Hi all,

I am doing my testing on oyster flavoring to determine the content of Tin
(Sn).
My sample preparation is using HNO3 with Microwave Digestion.
I will be using ICP OES.

However, I notice that Tin would not be soluble in HNO3.
Is this correct? Any idea on this?
If you happen to know any journal / article in Tin determination, please
help me.

Thank you so much...

kunio