Seed/Angel Investor (not a partner/owner) - How to record the loan?

Several ways to do this, but since you know what the money was spent on, I think this is the easiest way.
Create the loan liability account in the chart of accounts

Use a journal entry
list each expense account and enter the amount spent as a debit
list the loan liability account and enter the total amount as a credit
save

@julie8466 

I would just add that the IRS limits the amount of start-up costs that can be expensed. 

Per the IRS:

Business start-up and organizational costs are generally capital expenditures. However, you can elect to deduct up to $5,000 of business start-up and $5,000 of organizational costs paid or incurred after October 22, 2004. The $5,000 deduction is reduced by the amount your total start-up or organizational costs exceed $50,000. Any remaining costs must be amortized.

Thank you Ruslter, is there an account I can use as a "holding account" for the total amount of the loan before I apply it to each expense?  I need to go through all the receipts to see what goes to what/who after I get the company up to date with what is just on the bank account (the Partner's also paid for things out of pocket prior to opening the bank account, I know how to record those).  

I knew there was a limit but I wasn't sure how much it was. Thank you for that added information!

 is there an account I can use as a "holding account" for the total amount of the loan before I apply it to each expense?  I need to go through all the receipts to see what goes to what/who after I get the company up to date with what is just on the bank account (the Partner's also paid for things out of pocket prior to opening the bank account, I know how to record those).  

You could make a cash type bank account title it partners or something, deposit the funds and use the partner liability account as the source account for the deposit.  Then enter checks, do not print, for each expense