If I pay off a private LOC loan to zero balance can I get a tax deduction on future interest if I use it for IP deposits now?

I am selling a property and could pay off a LOC that I have at the moment (currently used for private purposes) to get a zero balance.  If I then use the money as a deposit(s) on property purchases can I tax deduct the future interest since I was down to zero balance and the purpose of the loan has changed?  Or would I have to close the account and start a new one with a different account number? (main risk of doing that is that the LOC is secured against my PPOR which I think has gone down a bit in value so the LOC would not have as high a limit)