Preparation method of MCNCs/PMAA magnetically-controlled Raman aptamer sensor for antibiotic residue detection

Abstract

The invention relates to a preparation method of an MCNCs / PMAA magnetically-controlled Raman aptamer sensor for antibiotic residue detection. The method comprises the following steps: taking a prepared magnetic nano-microsphere MCNCs / PMAA chelate aptamer with high saturation magnetic susceptibility and biocompatibility as a capture probe, embedding an Au @ SiO2 core-shell nano particle of p-aminothiophenol as an enhanced substrate, taking chelate aptamer short chain complementary DNA as signal molecules and building the sensor by utilizing an aptamer technology and in combination with a surface-enhanced Raman spectroscopy to realize the study on the antibiotic residue detection. When antibiotics exist, the structure of the aptamer in a detection system is affected, and a specific recognition binding to the aptamer occurs, so that the release of the different concentrations of signal molecules under the existence of the different concentrations of antibiotics is caused; subsequently, magnetic absorption is performed on the detection system; free signal molecules released from a liquid supernatant can perform different degrees of amplification on Raman signals; according to a Raman characteristic peak map of markers with different Raman intensities, the purpose of the sensitive indirect antibiotic residue detection is achieved.

Description

technical field [0001] The invention relates to a method for preparing an MCNCs / PMAA magnetically controlled Raman aptamer sensor for antibiotic residue detection, in particular to combining sensor technology and Raman technology to prepare MCNCs / PMAA magnetic nano-microspheres for chelating nucleic acid aptamers. The ligand is a capture molecule, Au@SiO embedded with p-mercaptoaniline (label) 2 Core-shell nanoparticles are used as enhanced substrates to chelate ligands and short-chain complementary DNA as signal molecules to achieve rapid, sensitive and effective detection of typical antibiotic residues. Background technique [0002] With the widespread use of antibiotics, a series of problems caused by their residues have followed. Investigations have shown that antibiotic residues in animal foods are an important factor in inducing childhood obesity, which makes the detection of residual antibiotics particularly important. Commonly used antibiotic residue analysis method...

AI Technical Summary

Problems solved by technology

[0003] At present, using MCNCs / PMAA magnetic nanospheres-aptamers as capture probes and cDNA-APS as signal molecules to construct a sensor system for sensitive and effective detection of antibiotic residues has not been reported.

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