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Heavy metal pollution caused wide public concern.Exposure to toxic heavy metal ions such as Cd2+,Pb2+,and Hg2+ can exert direct impact on human health.Over the last decades,metal ions determination represents an interest in environmental field.A number of analytical methods have been developed,including atomic absorption/emission spectroscopy,mass spectrometry,and electrochemical and fluorescent techniques.Although these conventional techniques are sensitive,most of them need a pre-concentration step,which is time and labor-consuming.Therefore,the need for rapid and sensitive analysis has motivated great research efforts.Surface enhanced Raman scattering(SERS)spectroscopy provides an alternative tool for fast screening of heavy metal contaminated environmental samples.SERS detection of heavy metal is a challenge because of the poor Raman activity of heavy metal ions.Therefore,modified NPs with new properties and functionalities are synthesized to capture metal ions to metal surfaces.The functional groups generally include DNA,disulfide anchoring group,and dye molecules.Herein,we propose a practical approach integrating substrate preparation and modification in one portable SERS platform.Chloroauric acid was reduced by dopamine through a facile one-step approach.By taking advantage of the unique SERS property of Au nanoparticles(NPs),and the specific reaction of dopamine upon binding to Pb2+ and Cd2+,we proposed a novel SERS sensor for sensitive detection of Pb2+ and Cd2+ ions.The as-prepared Au NPs can be used as active substrate for SERS detection of Pb2+ and Cd2+ ions in water.Complementary instruments including UV-vis spectrophotometer,high resolution transmission electron microscopy,and laser particle size analyzer were used to characterize the Au substrates.The results indicated that the Au NPs were stable and well-dispersed.Qualitative and quantitative determination of Pb2+ and Cd2+ ions was achieved based on the interaction of dopamine and heavy metals.The detection limit is 10-8 mol?L-1.The portable platform explored in this study should expand the application of SERS for in situ measurement of heavy metal pollutants.