Clenbuterol introduction and detection method
Clenbuterol Introduction Chinese name: Clenbuterol; Clenbuterol; scientific name Clenbuterol; is an antiasthmatic drug. The drug is neither a veterinary drug nor a feed additive, but an adrenal neurostimulant. Dichlorohydrin amine hydrochloride; Kechuansu; ammonia asthma; ambroxol; ammonia diclofenac; ammonia diclosanol. Manual Projector Screen,Cinema Screen,Movie Projector Screen,Pull-Down Projector Screen Dongguan Aoxing Audio Visual Equipment CO.,Ltd , https://www.aoxing-alr.com
Gas chromatography-mass spectrometry (GC-MS)
The advantage of GC-MS method is to combine the high-efficiency and rapid separation effect of chromatography and the high-sensitivity qualitative analysis of mass spectrometry. It can qualitatively and quantitatively analyze a specific residue in the presence of multiple residues. Higher detection limit. Fente C. A et al. Used GC-MS to detect CLB residues in cattle hair, with a minimum detection limit of 5 ng / g; For the detection of CLB content, the minimum detection limit is 2ng / g; Liu Qi et al. Used GC-MS (EI ion source) to detect CLB in swine urine, the detection limit was 0.5ng / mL; VanRhijin et al. Used trimethylsilyl or 2-Dimethylsilylmorpholine derivatives are used to detect CLB in urine extracts. Derivatives are scanned with electrical pulses or chemical ionization, which results in higher sensitivity. In addition, GC-MS method has higher detection sensitivity and lower false positive rate than HPLC method. Therefore, China has established GC-MS as the confirmatory method for detecting CLB (NY / T468 ~ 2001).
High performance liquid chromatography (HPLC)
HPLC is suitable for the determination of thermally unstable and highly polar β-agonists and their metabolites, and HPLC can be used in conjunction with pre-column extraction, purification and post-column fluorescence derivatization reactions and mass spectrometry (MS) systems for easy analysis Process automation. Huang Shixin et al. (1995) used an ultraviolet detector to detect CLB residues in pig liver and pork under the conditions of λ = 243nm, chromatographic column: shimpackCLC-ODS150 × 6.0mn, flow rate: 1mL / min, column temperature: room temperature 30 ℃, The minimum detection limit can reach 2ng / g [4]. Some people abroad used HPLC (diode array detector) to determine CLB residues in animal foods. The minimum detection limit was 1.26ng / g and the recovery rate was 98.9% [5]. At present, China has adopted HPLC as a semi-confirmed method for the detection of CLB residues. The minimum detection limit is 1-15 ng / g. Its advantages are good specificity, strong selectivity, high detection accuracy, and low false positive rate. The disadvantage is that the sample processing time is long, the detection process is cumbersome and difficult to operate, and expensive instruments are required, which is subject to certain restrictions in practical applications.
Enzyme-linked immunosorbent assay (ELISA)
Using the specific binding of immunological antigens and antibodies and the efficient catalytic action of enzymes, the plant horseradish peroxidase (HRP) and clenbuterol (CL) are chemically combined to form an enzyme-coupled clenbuterol. Combine the coated antibody (goat anti-rabbit IgG antibody) on the solid phase carrier with the specific anti-Clenbuterol antibody, and then add the test Clenbuterol and enzyme-coupled Clenbuterol, which are competitive with The clenbuterol antibody is combined, the substrate is added after washing, and the amount of clenbuterol to be measured is measured according to the change of the colored substance. If Clenbuterol is to be tested, less enzyme-coupled Clenbuterol is bound and the amount of colored matter is less. Determine the content of clenbuterol in the sample by visual inspection or colorimetry. The best wavelength for colorimetry is 450 nm, and the reference wavelength should be greater than 600 nm.
Colloidal gold immunochromatography
Using competitive colloidal gold immunochromatography technology, Clen in the detection solution combines with the gold label antibody on the gold label pad to form a complex. If the concentration of Clen in the detection solution is lower than the sensitivity value, the unbound gold label antibody flows to the T zone At the time, the Clen-BSA conjugate fixed on the membrane binds and gradually condenses into a visible T line; if the Clen concentration is higher than the sensitivity value, the gold-labeled antibodies all form a complex and will no longer bind to the Clen- BSA conjugates combine to form visible T lines. Unfixed compound flows through the T zone and is captured by the secondary antibody in the C zone and forms a visible C line. The appearance of line C indicates that immunochromatography has occurred, that is, the test strip is effective.
Liquid chromatography-mass spectrometry / mass spectrometry (HPLC-MS / MS)
Refer to SN / T 1924-2007 for the detection methods of residues of clenbuterol, ractopamine, salbutamol, terbutaline in foods of animal origin for import and export.
This standard is applicable to the determination of residues of clenbuterol, ractopamine, salbutamol, terbutaline in animal-derived muscle and internal organs.
The drug residue in the sample was extracted with ammonium acetate buffer solution at pH 5.2, and β-glucuronidase-arylthioesterase was added for enzymatic hydrolysis. Chromatography-mass spectrometry, internal standard method for quantification.