为实现水产品中抗生素和镇静剂的同时、快速检测,进行了题示研究。分取2.0 g匀浆后的样品的肌肉组织,加入体积比79∶1∶20的乙腈-乙酸-水混合溶液10 mL,振荡1 min,超声10 min。加入2.0 g氯化钠,振荡1 min,于-20 ℃保存30 min,用于去除提取液中的脂肪。离心10 min,分取1 mL上清液注入装载有150 mg C₁₈的CAFS clean-up净化柱中,多次推动活塞,将提取液全部转移到2 mL离心管中。分取0.5 mL净化液,加入0.5 mL 0.1%(体积分数,下同)甲酸溶液,混匀后过0.22 μm尼龙滤膜。滤液注入高效液相色谱-三重四极杆复合线性离子阱质谱仪,9种目标物在BEH C₁₈色谱柱上用不同体积比的0.1%甲酸溶液和含0.1%甲酸的甲醇溶液的混合溶液进行梯度洗脱分离后,用电喷雾离子源正离子(ESI⁺)模式电离,多反应监测(MRM)模式检测,基质匹配法定量。结果显示,9种目标物的质量分数分别在1.0~50.0 μg·kg^-1(丁卡因、布比卡因、恩诺沙星和氧氟沙星)、2.0~50.0 μg·kg^-1(地西泮和氟罗沙星)、5.0~50.0 μg·kg^-1(环丙沙星、培氟沙星和洛美沙星)内与对应的峰面积呈线性关系,检出限为0.2~1.0 μg·kg^-1;对空白草鱼样品进行3个浓度水平的加标回收试验,回收率为99.1%~110%,测定值的相对标准偏差(n=6)分别为1.9%~8.2%(日内精密度试验)和2.6%~8.5%(日间精密度试验)。方法用于28份水产品的分析,检出了1种镇静剂布比卡因(检出量为1.41 μg·kg^-1)以及4种氟喹诺酮类抗生素[洛美沙星、培氟沙星、环丙沙星(3种抗生素检出量均低于测定下限)和恩诺沙星(检出量为2.43~4.61μg·kg^-1,低于GB 31650-2019规定的限量)]。

In order to realize the simultaneous and rapid determination of antibiotics and sedatives in aquatic products, the study mentioned by title was carried out. An aliquot (2.0 g) of muscle tissue of the sample homogenized was taken, and 10 mL of acetonitrile-acetic acid-water mixed solution at volume ratio of 79∶1∶20 was added. The mixture was shaken for 1 min, ultrasonicated for 10 min, and mixed with 2.0 g of sodium chloride. The mixture was shaken for 1 min, stored at -20 ℃ for 30 min to remove fat from the extract, and centrifuged for 10 min. An aliquot (1 mL) of supernatant was introduced into the CAFS clean-up column loaded with 150 mg C₁₈, and the extract was transferred into a 2 mL-centrifuge tube by pushing the piston several times. An aliquot (0.5 mL) of the purified solution was taken, and mixed with 0.5 mL of 0.1% (volume fraction, the same below) formic acid solution. The mixed solution was passed through a 0.22 μm nylon filter membrane, and the filtrate was introduced into the high performance liquid chromatograph-triple quadrupole/composite linear ion trap mass spectrometer, and the 9 targets were separated on the BEH C₁₈ column with mixed solutions composed of 0.1% formic acid solution and methanol solution containing 0.1% formic acid at different volume ratios by gradient elution, ionized by ESI⁺ mode, detected by MRM mode, and quantified by the matrix matching method. As shown by the results, linear relationships between values of the mass fraction and the peak area of the 9 targets were kept in the ranges of 1.0-50.0 μg·kg^-1 (tetracaine, bupivacaine, enrofloxacin and ofloxacin), 2.0-50.0 μg·kg^-1 (diazepam and fluroxacin), and 5.0-50.0 μg·kg^-1 (ciprofloxacin, pefloxacin and lomefloxacin), with detection limits (3S/N) in the range of 0.2-1.0 μg·kg^-1. Test for the spiked recovery was made on the blank grass carp sample in the 3 concentration levels, giving recoveries in the range of 99.1%-110%, and RSDs (n=6) of the determined values were in the ranges of 1.9%-8.2% (intra-day precision test) and 2.6%-8.5% (inter-day precision test). The proposed method was applied to the analysis of 28 aquatic products, 1 bupivacaine of sedative (the detection amount was 1.41 μg·kg^-1), and 4 fluoroquinolone antibiotics of lomefloxacin, pefloxacin, ciprofloxacin (detection amounts were lower than the lower limit of determination) and enrofloxacin [detection amounts were in the range of 2.43-4.61 μg·kg^-1, lower than the limit specified by GB 31650-2019] were detected.