Sogne Vanessa, Meier Florian, Klein Thorsten, Contado Catia
University of Ferrara, Department of Chemical and Pharmaceutical Sciences, via L. Borsari, 46, 44121 Ferrara, Italy; Postnova Analytics GmbH, Max-Planck-Straße 14, 86899 Landsberg am Lech, Germany.
Postnova Analytics GmbH, Max-Planck-Straße 14, 86899 Landsberg am Lech, Germany.
J Chromatogr A. 2017 Sep 15;1515:196-208. doi: 10.1016/j.chroma.2017.07.098. Epub 2017 Aug 1.
The dimensional characterization of insoluble, inorganic particles, such as zinc oxide ZnO, dispersed in cosmetic or pharmaceutical formulations, is of great interest considering the current need of declaring the possible presence of nanomaterials on the label of commercial products. This work compares the separation abilities of Centrifugal- and Asymmetrical Flow Field-Flow Fractionation techniques (CF3 and AF4, respectively), equipped with UV-vis, MALS and DLS detectors, in size sorting ZnO particles, both as pristine powders and after their extraction from cosmetic matrices. ZnO particles, bare and superficially modified with triethoxycaprylyl silane, were used as test materials. To identify the most suitable procedure necessary to isolate the ZnO particles from the cosmetic matrix, two O/W and two W/O emulsions were formulated on purpose. The suspensions, containing the extracted particles ZnO, were separated by both Field-Flow Fractionation (FFF) techniques to establish a common analysis protocol, applicable for the analysis of ZnO particles extracted from three commercial products, sold in Europe for the baby skin care. Key aspects of this study were the selection of an appropriate dispersing agent enabling the particles to stay in stable suspensions (>24h)and the use of multiple detectors (UV-vis, MALS and DLS) coupled on-line with the FFF channels, to determine the particle dimensions without using the retention parameters. Between the two FFF techniques, CF3 revealed to be the most robust one, able to sort all suspensions created in this work.
考虑到当前商业产品标签上需要标明可能存在的纳米材料，对分散在化妆品或药物制剂中的不溶性无机颗粒（如氧化锌ZnO）进行尺寸表征具有重要意义。这项工作比较了配备紫外可见、多角度激光光散射（MALS）和动态光散射（DLS）检测器的离心场流分馏技术（CF3）和非对称流场流分馏技术（AF4）在对ZnO颗粒进行尺寸分选时的分离能力，这些颗粒既作为原始粉末，也作为从化妆品基质中提取后的样品。使用了裸露的以及用三乙氧基辛基硅烷进行表面改性的ZnO颗粒作为测试材料。为了确定从化妆品基质中分离ZnO颗粒所需的最合适方法，特意配制了两种水包油（O/W）乳液和两种油包水（W/O）乳液。含有提取出的ZnO颗粒的悬浮液通过两种场流分馏（FFF）技术进行分离，以建立一个适用于分析从欧洲销售的三种用于婴儿皮肤护理的商业产品中提取的ZnO颗粒的通用分析方案。本研究的关键方面包括选择一种合适的分散剂以使颗粒保持稳定悬浮（>24小时），以及使用与FFF通道在线联用的多个检测器（紫外可见、MALS和DLS），以便在不使用保留参数的情况下确定颗粒尺寸。在这两种FFF技术中，CF3显示出更强的适用性，能够对本工作中制备的所有悬浮液进行分选。
