Luna, a five-time winner on the Ladies European Tour, struck seven birdies to move onto nine under par overall after Thursday's round of 67.
It could have been better for the Italian, who would be further ahead were it not for a bogey on the par-four 14th.
Overnight leader Stacey Keating will be hot on her heels and hoping to put Friday's disappointing one-over-par 71 behind her.
The 26-year-old Australian is looking for back-to-back titles on the Tour and started magnificently on Thursday with a round of 62 but she could not follow it up on Friday.
Carlota Ciganda, Anja Monke and Anne-Lise Caudal are in a tie for third on five under par overall.
Monke put herself into contention with the round of the day, the German recovering from a mediocre 72 on Thursday with a fabulous second-round 63.