Fig. 5. (A) UV-Vis spectra of the AuNS@Ag, AuNSs, AgNPs, physically mixed AuNSs–AgNPs, and the blank sample were prepared by adding 150 μL of 10 mM AgNO₃ into the ascorbic acid solution without using the AuNSs. Corresponding digital photographs (right inset) of these colloidal solutions. (B) Compared UV-Vis spectrum of the prepared AuNS@Ag samples using different 10 mM AgNO₃ volumes from 50 to 200 μL.