Characterization of Nanomaterials Using Field Flow Fractionation and Single Particle Inductively Coupled Plasma Mass Spectrometery (FFF-ICP-MS and SP-ICP-MS): Scientific Operating Procedure SOP-C.

摘要

Characterization of nanomaterials must include analysis of both size and chemical composition. Field Flow Fractionation (FFF) is a powerful tool for determining the size of nanoparticles. Through the use of a combination of common detectors, such as UV-VIS (Ultraviolet-Visible Spectrophotometry) absorbance, with advanced methods, such as ICP-MS (Inductively coupled plasma mass spectrometry), high-resolution nanoparticle sizing and compositional analysis at the mg/L concentration level can be obtained. Single particle counter ICP-MS (SP-ICP-MS) has increased sensitivity compared to Field Flow Fractionation Inductively coupled plasma mass spectrometry (FFF-ICP-MS), with detection and sizing concentrations of ng/L. Such low-level detection and characterization capability is critical to nanomaterial investigations at biologically and environmentally relevant concentrations. The techniques have been modified and applied to characterization of all four elemental constituents of Cadmium Selenide/Zinc Sulfide core-shell quantum dots, silver nanoparticles with gold seed cores, and gold nanoparticles. Additionally, sulfide coatings on silver nanoparticles can be detected as a potential means to determine environmental aging of nanoparticles. Extraction of nanoparticles from tissues is possible using tetramethylammonium hydroxide (TMAH). Though any analysis described above is possible, only SP-ICP-MS has been employed to detect tissue extracts. This SOP (Scientific Operating Procedure) describes the analysis of engineered nanoparticles (ENPs), through the various separation and detection techniques described above. These analytical tools were tested on a variety of gold and silver standard nanoparticles that have been extensively characterized.