SERS Detection Of Pb²⁺and Thrombin By Aptamer Regulating The Activity Of GONR/CDs Nanoenzyme

Part ? IntroductionThis article describes the principle of surface-enhanced Raman spectroscopy and the analysis and application of SERS in the environment.The recent progress in the preparation of GONR and CDs was reviewed.The application of aptamers in the field of analysis was introduced.Compared the different analytical methods of determination of lead ions and thrombin.Briefly describe the main research content and research significance of this topic.Part ? SERS detection of Pb²⁺ by aptamer regulating the activity of GONR nano-enzymeGONR nano enzyme has strong catalytic activity to the reduction of HAuCl₄ by or H₂O₂.When a lead aptamer present in the solution,lead aptamer binding on GONR surface had a good inhibitory effect on the catalytic activity of GONR nano enzyme.However,when add the lead ion,aptamers and lead ion could form a king of stable complexes,thus reducing the binding of aptamers to GONR,the GONR nano enzyme concentration was not combined with the increased activation system catalytic effect.With the increase of lead ion concentration,the rate of the system reaction increased and more gold nanoparticles were produced,and the SERS signal increased gradually added the VBB.The Apt-Pb?NO₃?₂-GONR₄-HAuCl₄-H₂O₂-VBB system showed a good linear relationship between the increase of SERS signal and the Pb²⁺ concentration in the range of 0.003-0.1?mo L/L.The detection limit is 0.0019?mol/L.A method for the determination of trace Pb²⁺ was established.Part ? SERS/RRs/Abs detection of thrombin by aptamer regulating the activity of CDs nano-enzymeCarbon quantum dots?CDs?have a strong catalytic effect on HAuCl₄-GLC reaction.When there is a thrombin aptamer?Aptamer?,Aptamer adsorbs on the surface of these CDs,resulting in a weakened catalytic effect;and when thrombin is present in the solution,a thrombin-Aptamer complex is formed,making Aptamer from the surface of the CDs.Desorption,at which time the CDs are released and the catalysis is enhanced.With the increase of thrombin concentration,the more desorbed CDs,the faster the reaction rate of HAuCl₄-GLC catalyzed,and the resulting gold nano-sol has a higher SERS effect.After adding the probe,the corresponding SERS peak linearly increases.The Apt-thrombin-CDs-HAuCl₄-GLC-VBB system showed a good linear relationship between the increase of SERS signal and the thrombin concentration in the range of 0.0115-0.115nmol/L thrombin.The detection limit was 0.0023 nmol/L.A method for the determination of trace thrombin was established.