Fig. 7: SERS detection sensitivity of PI/TiO₂/Ag-0.07 flexible fibers.

a SERS spectra of 4-ATP adsorbed on PI/TiO₂ and PI/TiO₂/Ag-0.07 substrates from a 1 × 10⁻⁵ M aqueous solution. b SERS spectra of the PI/TiO₂/Ag-0.07 substrate incubated with TC solutions at various concentrations