Fool about with explosive stuff (5)

I believe the answer is:
nitre
'explosive stuff' is the definition.
The definition and answer can be both substances as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'fool about' is the wordplay.
'fool' becomes 'nit' (both can mean a stupid person).
'about' becomes 're' ('re' means regarding or about).
'nit'+'re'='NITRE'
'with' acts as a link.
Can you help me to learn more?
(Other definitions for nitre that I've seen before include "Gunpowder ingredient" , "food preservative" , "explosive ingredient" , "Salt" , "explosive component" .)
