Fig. 1. Schematic diagram of assembly process of gold nano-colloid enhanced substrate. (a) 5 µL of gold nano-colloids are dropped onto silicon wafer as substrate; (b) volume of gold colloids decrease during natural drying; (c) gold colloids are dried completely to form golden films on silicon wafers

Fig. 2. SERS pretreatment. (a) Original SERS; (b) LabSpec software operation interface; (c) SERS after pretreatment

Fig. 3. UV-vis spectra of self-made gold colloids. (a) Au NPs; (b) Au NRs

Fig. 4. SEM morphology of gold nanoparticles. (a) Au NPs and particle size distribution; (b) Au NRs

Fig. 5. Normal Raman spectra (NRS) of CIP

Fig. 6. SERS of CIP based on different laser wavelengths

Fig. 7. NRS, SERS based on Au NPs substrate of CIP aqueous solution and Raman spectra of Au NPs substrate

Fig. 8. SERS based on Au NRs substrate of CIP aqueous solution and Raman spectra of Au NRs substrate substrate

Fig. 9. Stability research atlas. (a) Au NPs substrate; (b) Au NRs substrate

Fig. 10. SERS of chicken extracts containing 2.0×10^-6 CIP detected based on different enhanced substrates

Fig. 11. SERS images of different concentrations of CIP solution detected based on Au NPs substrate

Fig. 12. Working curves of CIP solutions with different concentrations detected based on Au NPs substrate. (a) 1167 cm^-1; (b) 1378 cm^-1

Fig. 13. SERS images of different concentrations of CIP solution detected based on Au NRs substrate

Fig. 14. Working curves of CIP solutions with different concentrations detected based on Au NRs substrate. (a) 1142 cm^-1;(b) 1269 cm^-1; (c) 1389 cm^-1