Study of adsorption of biological and nanoparticle solutions at the solid-liquid interface

With advances in micromechanical machining and nanotechnology, the sample volume needed for biological research and other analysis decreases. With small volume, sample-surface interactions including adsorption must be considered. These adsorption effects can be observed by analyzing light reflected from the solid-liquid interface, and the contact angle of a solution on the surface. Presented is the design and construction of an ellipsometer, a device used to analyze light reflected off of a solid-liquid interface to find interfacial properties, including thickness of a thin film formed by adsorption. The taq enzyme is shown to have a large change in contact angle from seventy degrees to about ten degrees over a short (ten minute) time period when placed on an SU-8 substrate, indicating a change in energy at the interface and a large amount of adsorption. Silane substrates are found to produce similar results. Ellipticity of a colloidal gold nanoparticle solution on a glass substrate is also observed, whose results are difficult to interpret due to bulk shifts in the sample. With the ellipsometer running correctly, it can be used for a number of experiments, including spectroscopic ellipsometry and Brewster angle microscopy, with some modifications.

Grantor dc:publisher

Kansas State University

Year dc:date.issued

2007

Author dc:creator

• Frost, Daniel Wayne

• Ellipsometry
• Adsorption
• Contact angle

Statement dc:rights

• © the author. This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Language dc:language.iso

en_US

Handle dc:identifier.uri

http://hdl.handle.net/2097/411

OAI record oai:identifier

https://krex.k-state.edu/server/oai/request?verb=GetRecord&metadataPrefix=dim&identifier=oai%3Akrex.k-state.edu%3A2097%2F411