Investigation of Metal-Dependence in DNAzymes and Applications of DNAzymes and Aptamers for Diagnostics

Practical applications of DNA in diagnostics and sensing were examined using DNAzymes and aptamers. Aptamers are nucleic acids which bind a specific chemical or biological moeity. By labeling DNAzymes and aptamers with colored gold nanoparticles, our laboratory had previously constructed colorimetric sensors for analytes recognized by these nucleic acids. In order to make these sensors more user-friendly, dipstick tests similar to the home pregnancy test were developed using lateral devices. Aptamers specific for adenosine and cocaine were used to develop diagnostic tests for these molecules, and the tests were capable of working in human serum. The 8-17 DNAzyme was used to develop a dipstick test for Pb2+, and we demonstrated its application in the detection of Pb2+ in paint in accordance with the federally defined threshold for paint to be classified as 'lead-based'. In addition, we also found that the dipstick tests can be made ∼10 times more sensitive than solution-based colorimetric tests using gold nanoparticles for detection of analytes with the naked eye. Finally, aptamer technology was also combined with superparamagnetic iron oxide nanoparticles, to make MRI contrast agents which showed a change in contrast upon binding target analytes, adenosine and thrombin, which is a first step towards developing aptamer-based contrast agents for molecular MRI, capable of imaging cellular events at the molecular level.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Chemistry

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Mazumdar, Debapriya

Contributors dc:contributor

• Lu, Yi

• Chemistry, Biochemistry

Language dc:language

eng

Identifier

(MiAaPQ)AAI3363033

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/84336