Fabrication of chitosan-silver nanoparticle hybrid 3D porous structure as a SERS substrate for biomedical applications

► We developed novel silver nanoparticle hybridized 3D porous chitosan SERS substrate. ► Thiolated single stranded DNA was measured at a low concentration of 5 pM. ► Chitosan-Ag NPs SERS substrate has a simple, low-cost, large-area and excellent biocompatibility.