The Surface Enhanced Raman Scattering Detection Of Aflatoxin B1 Based On Hydrogenbond

Surface enhanced Raman scattering?SERS?is the abnormal enhancement of the Raman scattering signal when the molecules adsorbed on the surface of the rough metal surface?such as gold or silver nanoparticles?or other nanoscale particles.The Raman signals of molecules adsorbed on the surface of the Raman substrate will be amplified by 106¹011 times and even single molecule can be detected.Because of its high sensitivity,simple operation and no need for sample pretreatment,surface enhanced Raman spectroscopy has broad application prospects in trace analysis.The hydrogen atom and strong electronegativity atoms combined by covalent bond,and if the weak electronegativity,small radius atom close,in between the molecules can form a kind of special interaction which hydrogen as a medium called hydrogen bonds.The binding energy of hydrogen bond is 2-8 kcal,which is a kind of specific molecular interactions stronger than Van der Waals' force and much weaker than covalent bond and electrovalent bond.Hydrogen bond is easy to form,so it is easy to become a method of molecular fixation,mostly used for enrichment and detection.The main work of this paper is to detect aflatoxin B1 combine with the effect of the fixation of hydrogen bonds and the high sensitivity of surface enhanced Raman scattering.The research contents are as follows:1.SERS detection of aflatoxin B1 based on the detection system of gold nanoparticlemelamine-aflatoxin B1.The gold nanoparticles of uniform particle size?55±10 nm?have been prepared from chloroauric acid reduced by citric acid.Gold nanoparticles were used as substrates than added melamine to absorbed on substrates.Aflatoxin B1 molecules were captured in cage like structure formed by melamine and aflatoxin B1 through hydrogen bond and near the surface Raman enhancement region of gold nanoparticles.SERS detection of aflatoxin B1 with the help of the Raman enhancement of gold nanoparticles.The line range of this method is 3×10^-10 mol/L³×10^-4 mol/L and the correlation coefficient is 0.96.The detection limit is 3×10^-10 mol/L.This method was used to detect aflatoxin B1 in spiked oil samples.Detectable amount of aflatoxin B1 from 4.13×10^-9 mol/L⁴.7×10^-5 mol/L,recovery from 82.6%⁹4.05% and RSD range from 8.51%¹6.38%.The method proposed by this paper is simple and rapid,possesses high sensitivity and good reproducibility,and can be used to detect aflatoxin B1 in oil.2.SERS detection of aflatoxin B1 based on core-shell nanoparticles that gold nanoparticles as core and poly-methyl acrylic acid as molecularly imprinted polymer.The gold nanoparticles have been prepared from chloroauric acid reduced by citric acid.Core-shell nanoparticles which gold nanoparticles as core and molecularly imprinted polymer as shell had been prepared by polymerization with aflatoxin B1 imprinted polymers and gold nanoparticles.Aflatoxin B1 was specific localization and captured by unique hole in molecularly imprinted polymer shell then highly sensitively SERS detected by the electromagnetic enhancement effect of gold nanoparticles core.The line range of this method is 3×10^-11 mol/L³×10^-4 mol/L and the correlation coefficient is 0.987.The detection limit is 3×10^-12 mol/L.This method was used to detect aflatoxin B1 in spiked oil samples.Detectable amount of aflatoxin B1 from 4.8×10^-9 mol/L⁴.9×10^-5 mol/L,recovery from 89.84%¹01.12% and RSD range from 3.51%¹5.44%.The method proposed by this paper is simple and rapid,possesses high sensitivity and good reproducibility,and can be used to detect aflatoxin B1 in oil.3.SERS detection of aflatoxin B1 based on core-shell nanoparticles that gold nanoparticles as core and polyacrylamide as molecularly imprinted polymer.Using acrylamide monomer molecules for the synthesis of molecularly imprinted polymers,molecularly imprinted polymer shell had been synthesized through chain reaction triggered by thermal polymerization in acetonitrile solution of gold nanoparticles,thus the molecularly imprinted polymer can be wrapped around the gold nanoparticles.By optimizing the ratio of functional monomer and crosslinking agent,the most suitable proportion was determined to obtain a suitable core-shell structure.The line range of this method is 3×10^-11 mol/L³×10^-4 mol/L and the correlation coefficient is 0.987.The detection limit is 3×10^-12 mol/L.This method was used to detect aflatoxin B1 in spiked oil samples.Detectable amount of aflatoxin B1 from 4.8×10^-9 mol/L⁴.9×10^-5 mol/L,recovery from 89.84%¹01.12% and RSD range from 3.51%¹5.44%.