title: Gold Nanorod-pNIPAM Hybrids with Reversible Plasmon Coupling: Synthesis, Modeling, and SERS Properties.
abstract: The thermoresponsive optical properties of Au nanorod-doped poly(N-isopropylacrylamide) (Au NR-pNIPAM) microgels with different Au NR payloads and aspect ratios are presented. Since the volume phase transition of pure pNIPAM microgels is reversible, the optical response reversibility of Au NR-pNIPAM hybrids is systematically analyzed. Besides, extinction cross-section and near-field enhancement simulations for Au NR-microgel hybrids are performed using a new numerical method based on the surface integral equation method of moments formulation (M3 solver). Additionally, the Au NR-microgel hybrid systems are expected to serve as excellent broadband surface-enhanced Raman scattering (SERS) substrates due to the temperature-controlled formation of hot spots and the tunable optical properties. The optical enhancing properties related to SERS are tested with three laser lines, evidencing excitation wavelength-dependent efficiency that can be easily controlled by either the aspect ratio (length/width) of the assembled Au NR or by the Au NR payload per microgel. Finally, the SERS efficiency of the prepared Au NR-pNIPAM hybrids is found to be stable for months.
authors: †Departamento de Química Física, CINBIO, Universidade de Vigo and Instituto de Investigación Biomédica de Vigo (IBIV), 36310 Vigo, Spain.
authors: Cristina
authors: C
authors: Fernández-López
authors: †Departamento de Química Física, CINBIO, Universidade de Vigo and Instituto de Investigación Biomédica de Vigo (IBIV), 36310 Vigo, Spain.
authors: Lakshminarayana
authors: L
authors: Polavarapu
authors: ‡Departamento de Teoría de la Señal y Comunicaciones, Universidade de Vigo, 36310 Vigo, Spain.
authors: Diego M
authors: DM
authors: Solís
authors: §Departamento Tecnología de los Computadores y de las Comunicaciones, Universidad de Extremadura, 10003 Cáceres, Spain.
authors: José M
authors: JM
authors: Taboada
authors: ‡Departamento de Teoría de la Señal y Comunicaciones, Universidade de Vigo, 36310 Vigo, Spain.
authors: Fernando
authors: F
authors: Obelleiro
authors: ∥Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Málaga, 29071 Malaga, Spain.
authors: Rafael
authors: R
authors: Contreras-Cáceres
authors: †Departamento de Química Física, CINBIO, Universidade de Vigo and Instituto de Investigación Biomédica de Vigo (IBIV), 36310 Vigo, Spain.
authors: Isabel
authors: I
authors: Pastoriza-Santos
authors: †Departamento de Química Física, CINBIO, Universidade de Vigo and Instituto de Investigación Biomédica de Vigo (IBIV), 36310 Vigo, Spain.
authors: Jorge
authors: J
authors: Pérez-Juste
keywords: SERS; goldnanorods; hot spots; plasmon coupling; thermoresponsive microgels