Trace Element, Spectroscopy and Speciation Group (GETEE), Health Research Institute of Santiago de Compostela (IDIS), Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, Universidade de Santiago de Compostela, Avenida das Ciencias, s/n, 15782 Santiago de Compostela, Spain.
Trace Element, Spectroscopy and Speciation Group (GETEE), Health Research Institute of Santiago de Compostela (IDIS), Department of Analytical Chemistry, Nutrition and Bromatology, Faculty of Chemistry, Universidade de Santiago de Compostela, Avenida das Ciencias, s/n, 15782 Santiago de Compostela, Spain.
Talanta. 2019 Apr 1;195:23-32. doi: 10.1016/j.talanta.2018.11.023. Epub 2018 Nov 8.
A reliable sample pre-treatment based on enzymatic hydrolysis has been fully optimized and validated for TiO NPs isolation and determination/characterization in surimi (crab sticks). Efficient extractions have been found when using a pancreatin/lipase mixture at pH 7.4 and 37 °C for 12 h under continuous stirring. The proposed sample pre-treatment procedure has been found not to change TiO NPs size distribution, therefore guaranteeing TiO NPs integrity. TiO NPs determination (TiO NPs concentration) and TiO NPs characterization (size distribution) were assessed by single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) working with dwell times in the microsecond range (high frequency of data acquisition). Method validation was performed for TiO NPs concentrations and TiO NPs sizes. Good repeatability (25% and 8% for TiO NPs concentration and TiO NPs most frequent size), and sensitivity (limit of detection of 5.28 × 10 NPs gfor TiO NPs concentrations, and 31.3-37.1 nm for TiO NPs size) were obtained. Accuracy, calculated through analytical recovery was adequate. Recoveries for TiO NPs standards of 50 and 100 nm were 108 ± 5 and 105 ± 4%, respectively. The proposed methodology was applied to several surimi samples for assessing TiO NPs concentrations and size distribution. Some surimi samples were found to contain TiO NPs (concentrations from 1.40 × 10 to 1.19 × 10 NPs g). TiO NPs size distributions were very different among the samples, and some of them showed wide size ranges (the most frequent size varied from 53.8 to 62.1 nm; whereas, the mean size values were within the 73.4-217.5 nm range).
基于酶解的可靠样品前处理方法已被充分优化和验证，可用于从鱼糜（蟹棒）中分离和测定/表征 TiO NPs。当使用胰蛋白酶/脂肪酶混合物在 pH 7.4 和 37°C 下连续搅拌 12 小时时，发现可以进行有效的提取。研究发现，所提出的样品前处理程序不会改变 TiO NPs 的粒径分布，从而保证了 TiO NPs 的完整性。TiO NPs 的测定（TiO NPs 浓度）和 TiO NPs 的表征（粒径分布）采用工作在微秒范围内的单颗粒电感耦合等离子体质谱（sp-ICP-MS）进行评估（高频数据采集）。对 TiO NPs 浓度和 TiO NPs 粒径进行了方法验证。TiO NPs 浓度和 TiO NPs 粒径的重复性良好（TiO NPs 浓度和 TiO NPs 最常见粒径分别为 25%和 8%），灵敏度高（TiO NPs 浓度的检出限为 5.28×10 NPs g，TiO NPs 粒径为 31.3-37.1nm）。通过分析回收率计算得到的准确性是适当的。50nm 和 100nm TiO NPs 标准的回收率分别为 108±5%和 105±4%。该方法已应用于几种鱼糜样品，以评估 TiO NPs 的浓度和粒径分布。一些鱼糜样品中含有 TiO NPs（浓度从 1.40×10 到 1.19×10 NPs g）。样品之间的 TiO NPs 粒径分布差异很大，其中一些样品的粒径分布范围较宽（最常见粒径从 53.8nm 到 62.1nm 不等；而平均粒径值在 73.4nm 到 217.5nm 范围内）。
