Since the proposal of the Borexino project in the early nineties, the idea to perform a neutrinoless double beta decay experiment with 136Xe dissolved in the scintillator was considered. The beautiful results obtained by the Borexino experiment, which achieved a purity far exceeding design goals, and a new concept for dissolving large quantities of xenon in the scintillator by increasing its pressure make this possibility even more interesting for a new-generation experiment in the next decade. We present the ongoing R&D studies to look for neutrinoless double
beta decay using liquid scintillators, discussing the optical properties of the Borexino scintillator when xenon is dissolved in large quantity and with high pressure
