La, Ju A. Lee, Hyunjoo Kim, Dongchoul Ko, Hyungduk Kang, Taewook 2024-06-13T03:00:06Z 2024-06-13T03:00:06Z 2024-06-13 2024-06 1530-6984 https://pubs.kist.re.kr/handle/201004/150074 Three-dimensional gold and its alloyed nanoporous structures possess high surface areas and strong local electric fields, rendering them ideal substrates for plasmonic molecular detection. Despite enhancing plasmonic properties and altering molecular interactions, the effect of alloy composition on molecular detection capability has not yet been explored. Here, we report molecular interactions between nanoporous gold alloys and charged molecules by controlling the alloy composition. We demonstrate enhanced adsorption of negatively charged molecules onto the alloy surface due to positively charged gold atoms and a shifted d-band center through charge transfer between gold and other metals. Despite similar EM field intensities, nanoporous gold with silver (Au/Ag) achieves SERS enhancement factors (EF) up to 6 orders of magnitude higher than those of other alloys for negatively charged molecules. Finally, nanoporous Au/Ag detects amyloid-beta at concentrations as low as approximately 1 fM, with SERS EF up to 10 orders of magnitude higher than that of a monolayer of Au nanoparticles. English American Chemical Society Enhanced Molecular Interaction of 3D Plasmonic Nanoporous Gold Alloys by Electronic Modulation for Sensitive Molecular Detection Article 10.1021/acs.nanolett.4c01505 1 Nano Letters, v.24, no.23, pp.7025 - 7032 Nano Letters 24 23 7025 7032 N scie scopus 001239417000001 Chemistry, Multidisciplinary Chemistry, Physical Nanoscience & Nanotechnology Materials Science, Multidisciplinary Physics, Applied Physics, Condensed Matter Chemistry Science & Technology - Other Topics Materials Science Physics Article CATALYSTS FILMS Electronic modulation of alloy Surface interactionof charged molecules Nanoporous structure Plasmonicalloys Plasmonic molecular detection