Fig. 3: Surface-enhanced plasmonic sensor.

a Schematic of the surface-enhanced fluorescence principle. Reprinted with permission from ref. ⁶⁶ (Royal Society of Chemistry). b HIV detection platform over gold NP array. Reprinted with permission from ref. ⁶⁹ (American Chemical Society). c Illustration of a lateral flow-based SERS system presenting (i) AuNS–ATP–mAb SERS tag fabrication, (ii) proposed sensing device, and working principle of the sensor (iii) with and (iv) without influenza A nucleoprotein. Reprinted with permission from ref. ⁷⁶ (Royal Society of Chemistry). d An example of a SEIRA platform for tobacco mosaic virus (TMV) mapping: (i) TMV protein structure, (ii) topographical image of TMV over a silicon substrate, (iii) IR, near-field phase mapping at two different frequencies (1660 and 1720 cm⁻¹), and (iv) nano-FTIR spectrum of TMV. Reprinted with permission from ref. ⁸⁹ (Springer Nature).