Using Fluorescence Lifetimes to Characterize Lipid Behavior in Nanodiscs

Author

Cynthia Janku, University of MontanaFollow

Graduation Year

2017

Graduation Month

May

Document Type

Thesis

Degree Name

Bachelor of Science

School or Department

Chemistry and Biochemistry

Major

Biochemistry

Faculty Mentor Department

Biochemistry and Biophysics Program

Faculty Mentor

Sandy Ross

Faculty Reader(s)

Sandy Ross

Keywords

fluorescence, nanodiscs, biochemistry, biophysics

Subject Categories

Biochemistry

Abstract

Cellular uptake of molecules, including drugs, can be affected by the fluidity of the membrane. Nanoparticles have been hypothesized to alter membrane fluidity resulting in inflammation and its related clinical effects. Variations in phospholipids can alter membrane structure and its interaction with drugs or nanoparticles. To study membrane lipid differences and dynamics, we are using nanodiscs and liposomes as model systems. Nanodiscs are a lipid bilayer surrounded by a membrane scaffold protein, which is a derivative of Apolipoprotein A1, a protein involved in the removal of cholesterol from the body. There are important unresolved questions about how the belt protein affects the fluidity of the lipid bilayer. The goal of this project is to learn more about the behavior of lipid-protein interactions and how that affects membrane fluidity. Using nanodiscs made of either DMPC, DOPC, DOPS and cardiolipin with 5% NBD labeled lipid, we can take lifetimes of the nanodiscs at distinct wavelength intervals, which in concert can yield information about the relaxation rate of the lipid bilayers. Fluorescence lifetime is the time it takes between the fluorophores being excited by light and returning to the ground state by releasing photons. Liposomes of similar lipid compositions will be used as a control model system. This study will examine the effects of length and saturation of hydrocarbon tails, temperature, and the overall charge of the lipid to study the relaxation rates of the membranes.

Honors College Research Project

Yes

GLI Capstone Project

no

Recommended Citation

Janku, Cynthia, "Using Fluorescence Lifetimes to Characterize Lipid Behavior in Nanodiscs" (2017). Undergraduate Theses, Professional Papers, and Capstone Artifacts. 447.
https://scholarworks.umt.edu/utpp/447