Yánez-Jácome G S, Aguilar-Caballos M P, Gómez-Hens A
Department of Analytical Chemistry, Institute of Fine Chemistry and Nanochemistry (IQFN), Campus of Rabanales, Marie Curie Building (Annex), University of Cordoba, 14071 Cordoba, Spain.
Department of Analytical Chemistry, Institute of Fine Chemistry and Nanochemistry (IQFN), Campus of Rabanales, Marie Curie Building (Annex), University of Cordoba, 14071 Cordoba, Spain.
J Chromatogr A. 2015 Jul 31;1405:126-32. doi: 10.1016/j.chroma.2015.05.070. Epub 2015 Jun 5.
The usefulness of terbium oxide nanoparticles (Tb4O7NPs) as post-column derivatizing reagent for the liquid chromatographic determination of residues of quinolone antibiotics in milk samples has been studied. Seven quinolones of veterinary use have been chosen as model analytes to develop this method. The derivatization step is based on the formation of luminescent chelates of quinolones with Tb4O7NPs, which are monitored at λex=340nm and λem=545nm. Another relevant feature of the method is that the use of a 10-cm column and a ternary mixture of methanol, acetonitrile and acetic acid as mobile phase in gradient elution mode allow the chromatographic separation of the quinolones in about 13min, whereas previously described chromatographic methods require about 20min. The dynamic ranges of the calibration graphs and limits of detection are, respectively: 65-900ngmL(-1) and 35ngmL(-1) for marbofloxacin, 7.2-900ngmL(-1) and 2.5ngmL(-1) for ciprofloxacin, 6-900ngmL(-1) and 2ngmL(-1) for danofloxacin, 50-900ngmL(-1) and 20ngmL(-1) for enrofloxacin, 35-900ngmL(-1) and 12ngmL(-1) for sarafloxacin, 5-900ngmL(-1) and 2ngmL(-1) for oxolinic acid, and 7-900ngmL(-1) and 2.5ngmL(-1) for flumequine. The precision, established at two concentration levels of each analyte and expressed as the percentage of the relative standard deviation is in the range of 1.9-8.1% using standards, and of 3.4-10.7% in the presence of milk samples. The method has been satisfactorily applied to the analysis of skimmed, semi-skimmed and whole milk samples, with recoveries ranging from 89.0 to 106.5%.
研究了氧化铽纳米颗粒（Tb4O7NPs）作为柱后衍生试剂用于液相色谱法测定牛奶样品中喹诺酮类抗生素残留的实用性。选择了七种兽用喹诺酮类药物作为模型分析物来开发该方法。衍生化步骤基于喹诺酮类药物与Tb4O7NPs形成发光螯合物，在λex=340nm和λem=545nm处进行监测。该方法的另一个相关特点是，使用10厘米长的色谱柱以及甲醇、乙腈和乙酸的三元混合物作为流动相，采用梯度洗脱模式，可在约13分钟内实现喹诺酮类药物的色谱分离，而先前描述的色谱方法需要约20分钟。校准曲线的动态范围和检测限分别为：马波沙星65 - 900ngmL(-1)和35ngmL(-1)，环丙沙星7.2 - 900ngmL(-1)和2.5ngmL(-1)，达氟沙星6 - 900ngmL(-1)和2ngmL(-1)，恩诺沙星50 - 900ngmL(-1)和20ngmL(-1)，沙拉沙星35 - 900ngmL(-1)和12ngmL(-1)，恶喹酸5 - 900ngmL(-1)和2ngmL(-1)，氟甲喹7 - 900ngmL(-1)和2.5ngmL(-1)。在每个分析物的两个浓度水平下确定的精密度，以相对标准偏差百分比表示，使用标准品时在1.9 - 8.1%范围内，在有牛奶样品存在时为3.4 - 10.7%。该方法已成功应用于脱脂、半脱脂和全脂牛奶样品的分析，回收率在89.0%至106.5%之间。
