A highly porous PVA dried gel with gold nanoparticles embedded in the network as a stable and ultrasensitive SERS substrate.

We confirmed that the porous PVA dried gel with GNPs embedded in the network, which can be prepared very conveniently, is a stable and ultrasensitive 3D SERS substrate. The existence of the micropores within the gel is necessary for the ultrahigh sensitivity, and embedding of GNPs in the penetrable gel results in high stability.