Asymmetrical Flow Field Flow Fractionation Coupled to Nanoparticle Tracking Analysis for Rapid Online Characterization of Nanomaterials
Asymmetrical Flow Field Flow Fractionation Coupled to Nanoparticle Tracking Analysis for Rapid Online Characterization of Nanomaterials
复制标题
DOI：
10.1021/acs.analchem.0c00406
复制
发表时间：
2020-05-19
影响因子：
7.4
通讯作者：
Zhong, Wenwan
中科院分区：
文献类型：
--
作者：
Adkins, Gary Brent;Sun, Erica;Zhong, Wenwan
随着纳米材料在消费品、工业产品、医疗等领域的应用日益广泛，需要开发工具对纳米颗粒进行快速分离、量化和分级，以确保其安全和可持续的使用。虽然有许多技术可用于表征纯的、均一的纳米材料制剂，但由于合成条件不理想、产物不稳定引起的聚集或储存过程中的降解，对于非均相混合物来说，颗粒大小和计数仍然困难。在这里，纳米颗粒跟踪分析(NTA)被耦合到非对称在线流场流动分数(AF4)，使用分离器歧管实现在线颗粒分离和计数。通过合理的分流设计，AF4的高压和流量被降低到与NTA相容的水平，并使用注射泵通过NTA的出口抽出液体，并保持稳定的进入NTA的流量，以实现适当的颗粒大小。通过对平均直径为50、100和200 nm的聚苯乙烯颗粒混合物的分析，证实了AF4-NTA的成功偶联。进样量与联用系统测量值之间有很好的相关性。AF4-NTA在线和离线耦合得到的颗粒浓度也符合得很好。通过对金纳米棒、六方氮化硼纳米片等非球形纳米粒子的分析，证明了该体系的通用性。我们的工作已经证明，AF4-NTA可以实现对混合物中不同纳米材料种群的准确在线粒子计数，这是AF4或NTA单独无法完成的。这将是一种快速表征非均相纳米材料溶液的有价值的工具，无需提纯即可满足对含纳米材料产品的监管要求。
Increasing applications of nanomaterials in consumer goods, industrial products, medical practices, etc., calls for the development of tools for rapid separation, quantification, and sizing of nanoparticles to ensure their safe and sustainable employment. While many techniques are available for characterization of pure, homogeneous nanomaterial preparations, particle sizing and counting remains difficult for heterogeneous mixtures that resulted from imperfect synthesis conditions, aggregation from product instability, or degradation during storage. Herein, nanoparticle tracking analysis (NTA) was coupled to asymmetrical Online flow field flow fraction (AF4) using a splitter manifold to enable online particle separation and counting. The high pressure and flow rate in AF4 were reduced to the levels compatible with NTA by the proper flow splitting design, and a syringe pump was employed to withdraw fluid through the exit port of the NTA and maintain consistent flow rates entering NTA for proper particle sizing. Successful AF4-NTA coupling was demonstrated by analyzing a mixture of polystyrene particles with the average diameters of similar to 50, 100, and 200 nm. Good correlation was observed between the amount of each type of particle injected to and measured by the hyphenated system. The particle concentrations acquired using online and offline coupling of AF4-NTA also agreed well with each other. The nonspherical nanoparticles like gold nanorods and hexagonal boron nitride nanosheets were also analyzed to demonstrate the versatile applicability of this system. Our work has proved that AF4-NTA can achieve accurate online particle counting on different populations of the nanomaterials in a mixture, which cannot be done by either AF4 or NTA alone. It will be a valuable tool for rapid characterization of heterogeneous nanomaterial solutions without purification to fulfill the regulation requirement on the nanomaterial-containing products.