| AVS 61st International Symposium & Exhibition | |
| Spectroscopic Ellipsometry Focus Topic | Friday Sessions |
| Session EL+AS+BI+EM+SS-FrM |
| Session: | Application of SE for the Characterization of Organic and Biological Materials |
| Presenter: | Erika Pfaunmiller, University of Nebraska Lincoln |
| Authors: | E. Pfaunmiller, University of Nebraska Lincoln D. Peev, University of Nebraska-Lincoln D. Sekora, University of Nebraska-Lincoln S. Beeram, University of Nebraska Lincoln C. Rice, University of Nebraska-Lincoln M. Schubert, University of Nebraska-Lincoln T. Hofmann, University of Nebraska-Lincoln D. Hage, University of Nebraska-Lincoln |
| Correspondent: | Click to Email |
Slanted columnar thin films based upon SiO2 were deposited on glass substrates through the use of glancing angle deposition (GLAD). The typical length of these structures was between 500 nm and 2.5 µm. These thin films were then evaluated for use in ultra-thin layer chromatography (UTLC), which is a special type of thin layer chromatography (TLC) that uses supports that incorporate nanomaterials. In this work, a series of lipophilic dyes were analyzed through the use of both TLC and UTLC followed by detection through imaging ellipsometry. It has previously been demonstrated that changes in birefringence is seen as small organic molecules attach to some of the types of nanostructures that were used in this study. The principle behind the detection of organic chemicals that attach/adsorb onto such nanostructures is based on the variation of the optical anisotropy of highly-ordered 3D nanostructures with attached or adsorbed molecules. This causes screening of the dielectric displacement charges that are produced by the incident electromagnetic fields within the nanostructures, which can be measured as a variation of the effective birefringence of the highly-ordered 3D nanostructures. Measurement of this birefringence was done through generalized imaging ellipsometry. This combined imaging and separation approach should be useful for label-free detection in UTLC and for the chromatographic analysis of a various target compounds.