Winger Ashley Hodson also made a goalscoring comeback when she emerged from the bench to make her first appearance since April 2018 after suffering anterior cruciate ligament damage.
Further efforts from Laura Coombs, Courtney Sweetman-Kirk, Leandra Little and own goal completed the scoring as Vicky Jepson’s side set up a fifth round home clash with Millwall Lionesses.
With new signing Purfield starting at left-back, she was quickly into her stride and a potent threat attacking at will down the flanks.
After just two minutes she put in a fine cross that picked out Yana Daniels unmarked at the back post but the Belgium international was unable to hit the target.