Method for simultaneously detecting three antibiotic residues including streptomycin, chlorampenicol and tetracycline based on nucleic acid aptamer and quantum dots

Abstract

The invention relates to a method for simultaneously detecting three antibiotic residues including streptomycin, chlorampenicol and tetracycline based on nucleic acid aptamers and quantum dots and belongs to the technical field of analytical chemistry. Three-section complementary cDNA 1 sequences are designed and synthesized and are complemented with three antibiotic aptamers DNA sequences and are further complemented with respective capturing probe DNA sequences of three antibiotics and complementary cDNA 2 sequence part. The three cDNAs 1 are first hybridized with aptamer DNAs supplemented with each other to form double-stranded DNAs. When target antibiotics exist in a sample, the aptamer DNAs are combined with corresponding antibiotics as a priority to cause the double-stranded DNAs to be de-hybridized and release cDNAs 1. The free cDNAs 1 are combined with capturing probe DNAs modified on the surface of a gold electrode, and cDNAs 2 modified with three quantum dots are hybridized with the other end of each cDNA 1. The three quantum dots on the surface of the gold electrode generate dissolution volt-ampere peaks corresponding to the target antibiotics. The three antibiotics are detected by utilizing the relations of changes of peak current values and antibiotic concentration. The method is good in repeatability and stability and high in sensitivity and can be used for directly measuring the three antibiotic residues in samples such as milk.

Description

technical field [0001] The invention relates to a method for simultaneously detecting three antibiotic residues of streptomycin, chloramphenicol and tetracycline based on nucleic acid aptamers and quantum dots, belonging to the technical field of analytical chemistry. Background technique [0002] The scientific and rational use of antibiotics can benefit human beings, but inappropriate use can endanger human health. With the discovery that antibiotics can promote the growth of poultry and livestock, various antibiotics have been widely used in animal husbandry in many countries. Antibiotics are also used as additives in my country's feed industry, which play a very significant role in the prevention and control of animal diseases and have achieved significant economic benefits. However, the abuse of antibiotics has also caused adverse effects on animal husbandry. In recent years, many foods have been repeatedly exposed to contain antibiotic residues, posing potential safet...

AI Technical Summary

Problems solved by technology

Microbial detection method is widely used, its advantage is low cost, general laboratory can operate, but the measurement time is long, the result error is large, and the operation is complicated, so it cannot meet the needs of high-throughput and high-sensitivity quantitative detection

Instrument detection methods include gas chromatography (GC), high performance liquid chromatography (HPLC), liquid-mass chromatography (HPLC-MS), liquid chromatography-tandem mass spectrometry (HPLC-MS / MS), ultraviolet spectrophotometry The method (UV), enzyme-linked immunoassay (ELISA), etc., use the molecular structure and physical and chemical properties of antibiotics to separate and qualitatively and quantitatively measure. They have high sensitivity and good accuracy, but the equipment is often expensive, and it is also difficult for experimenters. High requirements, high requirements for sample pretreatment, time-consuming analysis and difficult to promote

The abuse of antibiotics will also cause multiple antibiotic residues to exist in animal-derived foods at the same time, so it is of great significance to establish an efficient and sensitive method for the simultaneous detection of multiple antibiotic residues

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