Aligned diphenylalanine nanotube–silver nanoparticle templates for high-sensitivity surface-enhanced Raman scattering

Self-assembly offers potential routes for large-scale, rapid, and cost-effective surface-enhanced Raman scattering (SERS) substrate designs. Here, a highly sensitive SERS template is reported, which utilizes aligned diphenylalanine nanotubes to form a dense packing arrangement of plasmon-active silver nanoparticles. The template is stable under high laser illumination with a power density of ~6.25 MW/cm2 in comparison to only silver nanoparticles and enables picomolar and femtomolar probe molecule concentrations to be probed, indicative of single-molecule SERS detection.