Flexible SERS active substrates from ordered vertical Au nanorod arrays

SERS active flexible substrates were fabricated by droplet deposition of Au nanorod solutions on rigid surfaces and subsequent stamping of assembled nanorod arrays on photographic paper and plastic surfaces. With this method plasmonic SERS substrates whose active area was constituted by Au nanorods assembled in closely spaced vertical arrays were fabricated. The SERS performances of the flexible active substrates were investigated with model molecule 4-aminobenzenethiol (4-ABT), where detection in the μM concentration range and Enhancement Factors (EF) of 10⁵ were obtained. To demonstrate field-based applications, detection of food contaminant crystal violet (CV) below the recommended 5 nM limit of detection was achieved. Also, detection of drug-marker benzocaine traces by a swabbing technique was demonstrated.