Fig. 1. SEM images of silver nanoparticles with different particle diameters. (a) P1 silver nanoparticles; (b) P2 silver nanoparticles; (c) P3 silver nanoparticles; (d) P4 silver nanoparticles

Fig. 2. UV-VIS absorption spectrum and size distribution of silver nanoparticles. (a) UV-VIS spectrum of silver nanoparticles; (b) size distribution of silver nanoparticles

Fig. 3. Enhancement of silver nanoparticles. (a) SERS of silver nanoparticles with different particle diameters on same concentration of crystal violet; (b) Raman spectra of crystal violet

Fig. 4. SEM images of PML: (a) PML; (b) surface-enhanced PML; (c) surface silver nanoparticles

Fig. 5. SEM images of clustered boletus spores with silver colloid. (a) BBP spores; (b) BSF spores; (c) TPS

Fig. 6. Raman spectra in range of 1800-450 cm-1. (a) PML; (b) TPS

Fig. 7. SERS diagrams of PML and three boletus spores in range of 1800-450 cm-1