DEVELOPMENT OF A NEW CHIRAL MONOLITHIC CAPILLARY COLUMN AND A FLUORESCENCE SPECTROSCOPIC STUDY OF A SELECTIVE OFF-ON PET SENSOR FOR THE DETECTION OF ZINC IONS

In the first study, a new µ-HPLC column was developed using a monolithic silica gel as a column substrate for chiral separation by covalently modifying with (S, S)-Whelk-O1 chiral selector. The monolithic stationary phase was generated through a sol-gel process and prepared in situ in a 100 µm i.d. fused silica capillary tubing. The chromatographic performance was characterized in terms of retention factor, column efficiency, enantioselectivity and resolution, as well as the kinetics parameters affecting the separation. Comparison with a commercial particle packed HPLC column demonstrates a promising enantioselective resolving ability of the monolithic Whelk-O1 capillary column. The second project focuses on characterization of fluorescent sensor for zinc detection. In this work, we have examined the photophysical properties of the fluorescent probe sensor that has been developed in our laboratory for Zn2+ recognition via a photo-induced electron transfer (PET) sensing mechanism. To characterize the fundamental function of sensor, response curves have been conducted, using acetone/methanol (199:1), 1,4-dioxane, acetone, methanol and aqueous buffer as the solvent system. Similar to prior work from our group, the sensor was found to respond selectively to Zn2+ ions with fluorescence enhancement. The fluorescence properties and binding response were evaluated in the presence of water and a Lewis base, which we found to have a marked effect on the fluorescence signal. The selectivity of the sensor for Zn2+ was also observed and compared to other divalent metal such as Ca2+, Mg2+, Cu2+ and Hg2+ with the goal of learning fundamental information on the system that can aid in the development of future PET based sensors.

Name thesis:degree_name

Doctor of Philosophy

Level thesis:degree_level

Campus Only Dissertation

Discipline thesis:degree_discipline

Chemistry

Year dc:date.available

2016

Author dc:creator

• Wang, Xiaoli

Contributors dc:contributor

• McCarroll, Matthew

• capillary
• chiral separation
• fluorescent probe
• fluorescent sensor
• monolith
• zinc sensor

Repository record dc:identifier

https://opensiuc.lib.siu.edu/dissertations/1159

OAI identifier oai:identifier

oai:opensiuc.lib.siu.edu:dissertations-2163