The Swiss international was reported to be on the verge of leaving the Gunners in the summer, but a move away from the Emirates Stadium failed to materialise.
The 25-year-old's two appearances for his club this season have come in the Capital One Cup.
Djourou, previously linked with Roma, is now said to be interesting the club currently third in Serie A, but agent Flavio Ferraria says nothing has been decided.
"At the moment there has been no contact with Napoli and even with other Italian clubs," he told calciomercato.it.
"No decision on his future has been taken yet, everything will be decided when we meet with Arsenal in the next few weeks.
"At the moment there has been no contact with any club."