Fig. 4From: SERS Detection of Dopamine Using Label-Free Acridine Red as Molecular Probe in Reduced Graphene Oxide/Silver Nanotriangle Sol SubstrateAbsorption spectra of the AR-DA system. (a)1.75×10−6 mol/L AR-pH 6.0 PBS; (b) (a)-25 μmol/L DA; (c) (a)-50 μmol/L DA; (d) (a)-100 μmol/L DA; (e) (a)-175 μmol/L DA; (f) (a)-250 μmol/L DA; (g) (a)-375 μmol/L DA; (h) (a)-500 μmol/L DABack to article page