Changtian Chen - PhD Final Oral Exam

Monday, April 29, 2019 - 2:30pm to 5:00pm

Major Professor:
   Wei Wang

Co-Major Professor:
   Steven A Whitham

Home Department:
   Plant Pathology and Microbiology

Title of Defense:
   Development of an aptamer-based nanosensor for SA detection and exploration of the role of SA in stress granule formation

   Salicylic acid (SA) is a phenolic phytohormone regulating immune responses against pathogens. SA and its derivatives can be found in diverse food products, medicines, cosmetics and preservatives. While salicylates have potential disease-preventative activity, they can also cause health problems to people who are hypersensitive. The current SA detection methods are costly, labor-intensive and require bulky instruments. In my study, a structure-switching aptamer-based nanopore thin film sensor was developed for cost-effective, rapid, sensitive and simple detection of SA. SA is a challenging target for aptamer selection using conventional systemic evolution of ligands by exponential enrichment (SELEX) due to its small size and scarcity of reactive groups for immobilization. By immobilizing the SELEX library instead of SA and screening the library using a structure-switching SELEX approach, a high affinity SA aptamer was identified. The integration of SA aptamer and nanopore thin film sens