Term of Award

Spring 2024

Degree Name

Master of Science, Applied Physical Science

Document Type and Release Option

Thesis (open access)

Copyright Statement / License for Reuse

Digital Commons@Georgia Southern License


Department of Chemistry and Biochemistry

Committee Chair

Nathaniel Shank

Committee Member 1

Mark Dela Cerna

Committee Member 2

Mitch Weiland


Light-driven molecular switches that can be turned on and off on demand have found many biological applications. For DNA, RNA, and synthetic derivatives, the switch can be used to interfere with a hybridization event with a complementary strand. To explore this potential, we have synthesized three light-sensitive PNA which have an azobenzene group (PNA-5azo5 and PNA-4azo4), and two azobenzene groups (PNA-2azo5azo2) as part of the PNA backbone. UV experiments were used to verify the conversion to the cis-isomer from the initial trans state for all of the single-stranded Azo-PNA ( PNA-5azo5, PNA-4azo4, and PNA-2azo5azo2) by irradiating at 365 nm with a LED light while monitoring the cis absorption at 200 – 600 nm. Conversion back to the trans isomer was explored using light (490 nm) and thermal relaxation. Light-driven isomerization of the same oligomer back to the trans-isomer showed nearly full restoration of the isomer when irradiated at 490 nm at 20 ˚C. Interestingly, thermal conversion (in the dark) required elevated temperatures and time (5 h at 60 oC, PNA-2azo5azo2) to return the trans-isomer. Unfortunately, ELISA readouts, the melting curve analysis, and UV Vis spectroscopy for the PNA duplexes showed that regardless of the PNA isomerization, the duplexes maintained their stability.

Research Data and Supplementary Material


Available for download on Friday, April 18, 2025