Method of rapidly determining fluoroquinolone type medicines in faeces of livestock and poultry

Abstract

The invention relates to a novel method of extracting fluoroquinolone type medicines in faeces of livestock and poultry. The method includes 1) grinding a freeze-dried sample of faeces of livestock and poultry, and sieving; 2) weighing 0.50-1.00 g of the sample, adding into a centrifuge tube, adding 5-10 mL of a calcium chloride-hydrochloric acid buffer solution having a concentration of 50%, performing vortex mixing for 1 min, performing ultrasonic extraction for 15-30 min, centrifuging at a speed of 4500 r / min for 10 min, and collecting the supernate; 3) separately subjecting standard samples of one or more than two of the fluoroquinolone type medicines to qualitative analysis by a high performance liquid chromatography instrument, and determining retention time; 4) creating a standard curve for each fluoroquinolone type medicine compound by adopting peak area as a vertical coordinate and adopting a concentration (ng / mL) corresponding to each fluoroquinolone type medicine as a horizontal ordinate; and 5) measuring the content of each target compound in the sample to be measured by high performance liquid chromatography, determining the type of each target compound according to the retention time, and determining the content of each target compound according to the corresponding standard curve. The method is good in repeatability and high sensitivity.

Description

technical field [0001] The invention relates to the determination of fluoroquinolones in livestock and poultry manure, in particular to a new extraction method for fluoroquinolones in livestock and poultry manure. Background technique [0002] Fluoroquinolones are a class of fully synthetic antibacterial drugs, which are chemically related to nalidixic acid, and their mechanism of action is to directly act on the nucleus of bacteria and inhibit the DNA gyrase of bacteria, so that the enzyme cannot introduce nicks on the DNA double strand , destroy the metabolism and reproduction of bacteria, and quickly kill bacteria. Originally used to treat urinary tract infections, these drugs have now been developed to treat systemic infectious diseases, and are commonly used as preventive and therapeutic drugs in the breeding industry. Fluoroquinolones have poor absorption in animals, and more than 75% of them will be excreted in the form of the original drug (Reference 1: Guan Holland...

AI Technical Summary

Problems solved by technology

The use of the above methods has the following disadvantages: 1) Other methods mostly use organic reagents for extraction, which is harmful to the human body; 2) The subsequent steps of the extraction of some methods need to be separated by solid-phase extraction columns, which are more expensive and will cause complicated operations; 3) Partial The method mostly uses liquid phase tandem mass spectrometry, although it has lower sensitivity and does not require high resolution of samples, but there is a strong matrix effect, especially for complex fecal samples, and the use and maintenance costs of the instrument are high

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