Convert the variable

I got a variale which passing by other problem to pl/sql
colBuf="USER,NAME,LOC,DATE"


need to make it like this
tempcolBuf=||'^B'||bfary(i).user||'^B'||bfary(i).name||'^B'||bfary(i).loc||'^B'||bfary(i).date||'^B'

anyone can help? any command can use? or loop?
hopefully can get the solution by syntax...

Thank you