Fig. 1. Preparation process of Au-Nylon flexible film substrate

Fig. 2. SEM (a), EDS (b) and UV-Vis-NIR (c) spectra of Au-Nylon flexible film substrate

Fig. 3. SERS spectra of Au-Nylon flexible membrane substrate at different conditions on CV probe molecules (a) and SERS spectra of Au-Nylon flexible membrane substrate and Nylon flexible membrane on CV probe molecules and R6G probe molecules (b)

Fig. 4. Quantitative analysis of CV solution with Au-Nylon flexible membrane substrate (a) and linear relationship between peak strength and concentration at 1 171 cm^-1 (b)

Fig. 5. SERS collected from 15 different points (a); Histogram of the peak of CV at 1 171 cm^-1 (b)

Fig. 6. SERS diagram of Au-Nylon flexible membrane substrate (5 batches) for CV

Fig. 7. SERS spectra of S. aureus with gold colloid, Nylon film and Au-Nylon flexible film substrate