A Novel SPR-RRS And SERS Analytical Platform For Detection Of Trace Potassium And Amonian Based On Aptamer And Ligand-regulation Of Nanosilver Catalysis

Resonance Rayleigh scattering?RRS?spectroscopy is a simple,rapid and sensitive method that has been widely used in drugs,proteins and environmental analysis.Surface enhanced Raman scattering spectroscopy?SERS?not only can detect the molecules adsorbed to the monomolecular and sub-molecular layers of the metal surface,but also give the structural information of the surface molecules,which is fast,sensitive,informative and selective.In this paper,RRS and SERS are used for determination of trace potassium ion and ammonium ion by combining the reaction of nucleic acid aptamers,ligand and Ag nanoenzyme with RRS and SERS spectroscopy.The Specific research work mainly covers the following areas:1.At room temperature,the both reactions of H₂O₂-HAuCl4 and glucose-AgNO3 are slow,and small particle size of silver nanoparticles have strong catalytic effect on the reaction.The reaction product gold nanoparticles exhibited a strong Resonance Rayleigh scattering?RRS?peak at 370nm.Victoria blue B?VBB?as surface-enhanced resonance Raman scattering?SERS?probe exhibited a strong SERS peak at 1616cm^-1 in the nanogold sol substrate.The experimental results shows,when gold nanoparticles which was synthesized through NaBH4 reduction process?AgNPB?as catalysts,the increased RRS intensity I370nm and SERS intensity I1615cm^-1 responds linearly with the concentration of AgNPB over 0.05-0.80?mol/L.In this paper,silver nanoparticles,such as AgNP,AgNT and AgNRs had catalytic activity to HAuCI4-H₂O₂,glucose-AgNO3 particles reaction.Nano-silver particles have strong nano-catalysis.After adding the aptamer,nano-silver particles are encapsulated by the aptamer,which can effectively reduce the catalytic effect of nano-silver,SERS/RRS signal is weak.With VB4r as SERS probe,AgNP has a strong catalytic effect.There was a good linear relationship between the concentration of AgNPs and the decrease of I1615cm^-1 in the range of 0.05-0.6?mol/L.In this aptamer reaction solution,Apt has a strong inhibitory effect on the reaction of nano-silver catalyzed H₂O₂-reduced HAuCl4-forming gold nanoparticles,and its product gold nanoparticles have a strong Raman scattering peak at 1615cm^-1.With the increase of Aptamer concentration,the catalytic effect is weakened,which leads to the decrease of the Raman scattering peak at 1615cm^-1.Apt concentration in the range of 0.5?16nmol/L and its Raman scattering peak reduction value/1615cm^-1 linear.When K+ is present in the solution,the affinity of Apt to AgNP is weakened due to the formation of Apt-K+ structure by K+ and Apt due to the strong affinity of the aptamer to potassium ions,so that AgNP is precipitated from AuNP-Apt and restored The catalytic effect of H₂O₂-HAuCl4/GLC-AgNO3 on the catalytic generation of nano-gold/silver,respectively,at I1615cm^-1 1616cm^-1 each have a strong Raman peak.With the increase of K+ concentration,the Raman peak at 1615cm^-1 and 1616 cm^-1 was linearly enhanced,and the K+ concentration was in the range of 50-4500 nmol/L and the SERS enhancement value I1615em^-1 was linear.Based on this,a new method of SERS and RRS for sensitive and simple detection of K+ aptamers nano-gold was established.2.The nano-silver particles are encapsulated by?C6H5?4BNa ligand,which can effectively reduce the catalytic effect of nano-silver,and the SERS/RRS signal is weaker,and the nano-silver particles have strong catalytic effect.With the VBB as SERS probe,AgNP has a strong catalytic effect.There was a good linear relationship between the concentration of AgNPs and the decrease of I1615cm^-1 in the range of 0.05-0.6?mol/L.In the aptamer reaction solution,the?C6H5?4BNa ligand has a strong inhibitory effect on the reaction of nano-silver catalyzed reduction of HAuCl4-generated gold nanoparticles.The gold nanoparticles have a strong Raman scattering peak at 1616cm^-1.With the increase of?C6H5?4BNa ligand concentration,the catalytic effect is weakened,which leads to the decrease of the Raman scattering peak at 1616cm^-1.The ligand concentration is in the range of 0.25-2.25p?mol/L and its Raman scattering peak decreases ?I1615cm^-1 linear.NH₄⁺ reacts with?C6H5?4BNa to form?C6H5?4BNH4 structure because of the strong affinity of?C6H5?4BNa ligand to potassium ions in the presence of NH₄⁺.Thereafter,the affinity of?C6H5?4BNa ligand to AgNP becomes Weak,so that AgNP from?C6H5?4BNa ligand precipitation and recovery of the catalytic effect of H₂O₂-HAuCl4/GLC-AgNO3 reaction catalyzed by the nano-gold/silver,respectively,at 1615 cm^-1,1616 cm^-1 each have a strong peak.With the increase of NH₄⁺ concentration,the Raman peak at 1615cm^-1 and 1616cm^-1 was linearly enhanced,and the concentration of NH₄⁺ in the range of 50-3500 nmol/L was linear with the SERS enhancement value ?I1615cm^-1.Based on this,a new method of SERS and RRS catalyzed by nano-gold nanoparticles with ligand and simple detection of NH₄⁺ was established.