液相色谱-离子阱-飞行时间串联质谱同时检测肉制品中14种杂环胺

建立了液相色谱-离子阱-飞行时间串联质谱(LCMS - IT - TOF)同时测定肉制品中14种杂环胺( HAAs)残留量的分析方法.样品以乙腈提取,经Phenomenex strata-X-C小柱净化,甲醇-氨水(9:1)洗脱,氮吹至干,经1 mL乙腈-水(1:9)定容离心后上机测定,基质曲线内标法定量.结果表明,...     

Monitoring of streptomycin and dihydrostreptomycin residual levels in porcine meat press juice and muscle via solid-phase fluorescence immunoassay and confirmatory analysis by liquid chromatography after post-column derivatization

A solid-phase fluorescence immunoassay (SPFIA) that was primarily developed for detection of antibiotic residues in milk was qualitatively applied for the pre-screening of the residues of aminoglycoside antibiotics, streptomycin and dihydrostreptomycin, in meat press juice. The confirmation of both analytes was performed using a validated method of highperformance liquid chromatography with post-column derivatization. The analytical performance was demonstrated by the analysis of pork meat samples spiked at three concentration levels, ranging from 0.25 to 2.5 ppm for each analyte. In general, the recoveries ranged from 80.4 to 81.5% and from 79.6 to 84.4% for streptomycin and dihydrostreptomycin, respectively, with relative standard deviations lower than 6%. The limits of detection were 0.1 and 0.15 ppm for streptomycin and dihydrostreptomycin, respectively, and the limits of quantification of 0.35 and 0.5 ppm are below the maximum residue limits of Codex, the European Union, and the Korean Food and Drug Administration (ranging from 0.5 to 0.6 ppm). Eight real samples collected from the Seoul area were first monitored using SPFIA, and none of them were found positive. These findings are in good accordance with those observed by HPLC analysis. To the best of our knowledge, this is the first report to monitor the aminoglycoside residues in pork meat press juice using SPFIA.     

离子对反相液相色谱-原子荧光光谱法测定畜禽肉中5种硒形态含量

建立了一种测定畜禽肉类中硒代胱氨酸、甲基硒代半胱氨酸、硒代蛋氨酸、硒酸根和亚硒酸根含量的离子对反相液相色谱-原子荧光光谱分析方法。样品中有机硒通过胰蛋白酶和蛋白酶（XIV,链霉蛋白酶）酶解提取,无机硒通过碘乙酰胺溶液提取,于55 ℃水浴200 r·min-1振荡提取20 h,提取液高速离心后再经超滤管离心净化,C18反相色谱柱分离,30 mmol·L-1磷酸氢二铵、0.5 mmol·L-1四丁基溴化铵和5% （V/V）甲醇为流动相,用20%（V/V）甲酸调节流动相溶液pH至6.0,离子对反相液相色谱-原子荧光光谱法测定样品溶液中5种硒形态含量。采用与标准样品对照法定性,峰面积外标法定量。保留时间定性,外标法峰面积定量。硒代胱氨酸、甲基硒代半胱氨酸、硒代蛋氨酸、硒酸根和亚硒酸根在5~200 μg·L-1范围内线性良好,相关系数均大于0.999,其检出限分别为0.89,0.78,0.55,0.94和0.70μg·L-1,加标回收率为76.8%~109%,批内精密度和批间精密度分别为2.7%~7.8%和3.5%~12.3%。本方法具有快速简便、灵敏和准确等优点,适用于畜禽肉类样品中硒形态分析测定。     

Rapid Full-Cycle Technique to Control Adulteration of Meat Products: Integration of Accelerated Sample Preparation,Recombinase Polymerase Amplification,and Test-Strip Detection

Verifying the authenticity of food products is essential due to the recent increase in counterfeit meat-containing food products. The existing methods of detection have a number of disadvantages. Therefore, simple, cheap, and sensitive methods for detecting various types of meat are required. In this study, we propose a rapid full-cycle technique to control the chicken or pig adulteration of meat products, including 3 min of crude DNA extraction, 20 min of recombinase polymerase amplification (RPA) at 39 °C, and 10 min of lateral flow assay (LFA) detection. The cytochrome B gene was used in the developed RPA-based test for chicken and pig identification. The selected primers provided specific RPA without DNA nuclease and an additional oligonucleotide probe. As a result, RPA–LFA, based on designed fluorescein- and biotin-labeled primers, detected up to 0.2 pg total DNA per μL, which provided up to 0.001% w/w identification of the target meat component in the composite meat. The RPA–LFA of the chicken and pig meat identification was successfully applied to processed meat products and to meat after heating. The results were confirmed by real-time PCR. Ultimately, the developed analysis is specific and enables the detection of pork and chicken impurities with high accuracy in raw and processed meat mixtures. The proposed rapid full-cycle technique could be adopted for the authentication of other meat products.