“…45 A recent report of the incipient ferroelectricity of oriented water molecules confined to the nano-channels of a crystal raises the possibility that also the residual water trapped by choline in the stereocomplex structures could contribute to the observed PFM signal. 46 The piezoresponse could also result from a local distortion of the PLLA and PDLA molecules in the SC, which could have a stretching effect similar to changes in the orientation of the CQO dipoles occurring in the shear ferroelectricity of PLA, 9,10 or a confinement-induced cooperative molecular orientation, 30,31 given the particular location of the SC at the spherulitic interfaces. Further detailed studies of the composition, structure and local piezoresponse of samples with large SC crystalline domains are necessary in order to clarify the underlying mechanism behind the observed PFM data, and, if possible, to fully exploit the potential of PLA SCs to produce new materials with the controlled piezoelectric performance for biomedical applications.…”