does Promissory Note have any legal affect?


I would appreciate some information.

I loan someone certain amount of money and get paid interest on this, i
have a promissory note contracting this and it is notarized. It also
mentioned in case of his death, I can collect my principle back etc

I am wondering does this note have any legal affect? hyporthetically,
in case of his death, can I use this note to go to court to collect my
principle ?

If not, what kind of document should I make for this loan to protect
myself in case of unexpected thigns.