Long-period fiber gratings (LPFGs) represent an attractive fiber grating-based technological platform because of their selective spectral features together with the intrinsic sensitivity to surrounding refractive index (SRI). Unfortunately, their main limitation relies on the necessity to opportunely coat the glass substrate when sensitivity enhancement and/or specific functionalization are required. Here, we investigate the possibility to realize a self-functionalized and highsensitivity LPFG by evanescent-wave interaction of the …