Investigation and design of SERS active nanoparticle assemblies via biological interactions

The overarching theme of this research was to further the understanding of the interactions of both the proteome and the glycome. An initial soft focus was placed upon increasing the stability of nanoparticles via the design of novel linker chemistries for nanoparticle functionalisation. From these initial studies, the synergic theme of studying different types of biological interactions using SERS has come to the forefront of this research. Novel nanotag synthesis has been detailed using a one-step functionalisation methodology. The stability of these nanotags has been investigated and found to be on par with the stability achieved using the current leading methods of nanotag functionalisation. Reproducible SERS spectra have been obtained in the presence of high electrolyte concentrations as well as in highly acidic conditions. These novel nanotags have been employed to differing degrees of success in a number of immunoassay formats. Successful detection has been achieved in a TMB ELISA format indicating that the biological integrity of the biomolecules attached to these nanotags remains intact following their functionalisation. Following the success of the linkers devised for nanotags synthesis several novel short chain carbohydrate linker groups were devised. These carbohydrate linkers were then attached to both gold and silver nanoparticle for deployment in the formation of nanoparticle assemblies mediated by the interaction with carbohydrate specific proteins known as lectins. The formation of these nanoparticle assemblies has shown to be dependent on the concentration of lectin present and as such, linear ranges of detection have been achieved using both extinction spectroscopy and SERS, which are unrivalled when using current detection methods. The converse of this approach, lectin functionalised nanoparticles, were employed as molecular imaging agents for the elucidation of the surface carbohydrate composition of multiple cell lines. These studies have been extended to detecting disease directed cellular modifications via binding to over expressed sialic acid residues present on prostate cancerous cells. This has elicited a method by which it may be possible to discriminate between both cancerous and non-cancerous cells in a clinical environment.

Name dc:type.qualificationname

phd

Level dc:type.qualificationlevel

doctoral-pg

Grantor dc:publisher.institution

University of Strathclyde

Year dc:date.issued

2013

Author dc:creator

• Craig, Derek

DOI

10.48730/a32w-ke18

Identifier

T13644

OAI identifier oai:identifier

oai:strathclyde:r494vk22c