Institute of Quality Standard and Testing Technology for Agro-Products, Key Laboratory of Agro-Product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Institute of Quality Standard and Testing Technology for Agro-Products, Key Laboratory of Agro-Product Quality and Safety, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Food Chem. 2020 Mar 30;309:125253. doi: 10.1016/j.foodchem.2019.125253. Epub 2019 Jul 25.
To ensure accurate and reliable measurement results, a whole liquid egg certified reference material (CRM) retaining the resemblance to real samples was first developed for improving measurement quality of enrofloxacin residue in eggs. The CRM raw material naturally containing enrofloxacin was obtained by sampling eggs from laying hens following oral administration of enrofloxacin. The homogenizing and bottling procedure was evaluated and applied on the bulk raw material to prepare the CRM candidate. For characterization of the CRM, liquid chromatography tandem isotope dilution mass spectrometry as a reliable reference method was studied and used for value assignment by all participating laboratories. The certified value was assigned to be 30.6 μg/kg with expanded uncertainty of 3.1 μg/kg (coverage factor k = 2, approximate 95% confidence interval) for enrofloxacin. In addition, homogeneity, long-term stability at -70 °C for one year and short-term stability at -18 °C, 4 °C and room temperature for nine days were assessed.
为了确保准确可靠的测量结果，首先开发了一种全蛋液认证参考物质（CRM），以提高鸡蛋中恩诺沙星残留量的测量质量。该 CRM 原材料是通过给产蛋母鸡口服恩诺沙星后采集鸡蛋获得的，其中自然含有恩诺沙星。对批量原材料的均化和装瓶程序进行了评估，并应用于制备 CRM 候选品。为了对 CRM 进行表征，研究了液相色谱串联同位素稀释质谱法作为一种可靠的参考方法，并由所有参与实验室使用该方法赋值。恩诺沙星的赋值结果为 30.6μg/kg，扩展不确定度为 3.1μg/kg（包含因子 k=2，约 95%置信区间）。此外，还评估了 CRM 的均匀性、在-70°C 下的长期稳定性（一年）以及在-18°C、4°C 和室温下的短期稳定性（九天）。
