Purse has joined Micky Adams' side after parting company with Vale's npower League Two rivals Plymouth, who ironically were the visitors to Vale Park on Saturday.
The 35-year-old was not eligible to play against Argyle but his contract with the Valiants will officially begin on Monday and he will go straight into the squad for next Saturday's top-of-the-table clash at Gillingham.
"Darren's experience speaks for itself, both as a player and a leader on the pitch," said Adams after Vale's 4-0 win over Plymouth.
"I was keen to add him to the squad after hearing of his availability, especially in light of the injury to John McCombe on New Year's Day.
"Darren is hungry to make a difference at Port Vale and I have no doubt that will show through his performances on the football field."
After starting his career at Leyton Orient, Purse has gone on to make over 450 Football League appearances, taking in spells at Birmingham, West Brom, Cardiff and Sheffield Wednesday.