Skip to main content
ARS Home » Pacific West Area » Davis, California » Western Human Nutrition Research Center » Obesity and Metabolism Research » Research » Publications at this Location » Publication #287800
Title: Direct comparison of fatty acid ratios in single cellular lipid droplets as determined by Raman spectroscopy and gas chromatography

Author
item SCHIE, IWAN - University Of California
item Pedersen, Theresa
item SMITH, ZACHARY - University Of California
item WU, JIAN - University Of California
item Newman, John
item HUSER, THOMAS - University Of California
item NOLTEL, LENA - Bielefeld University
item YAHIATENE, IDIR - University Of California

Submitted to: Analyst
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/15/2013
Publication Date: 8/15/2013
Citation: Schie, I.W., Pedersen, T.L., Smith, Z., Wu, J., Newman, J.W., Huser, T., Noltel, L., Yahiatene, I. 2013. Direct comparison of fatty acid ratios in single cellular lipid droplets as determined by Raman spectroscopy and gas chromatography. Analyst. doi: 10.1039/C3AN00970J.

Interpretive Summary: Lipid droplets inside cells are the least studied and least understood cellular organelles in eukaryotic and prokaryotic cells. Despite broad research efforts to understand the structure and function of lipid droplets it has previously not been possible to determine the composition of individual cellular lipid droplets. In this paper we present a novel data analysis approach called non-negative least-squares fitting to analyze a type of infra red spectra from single cellular lipid droplets to determine their composition after cellular exposure to different amounts of oleic and palmitic acid. By comparing the results from the single lipid droplet analysis to those from the gas chromatography mass spectrometry analysis of millions of cells, we show that the proposed method can accurately predict the relative amount of a fatty acid in the lipid droplet, and that the composition in a single lipid droplet is on average the same as that of all lipid droplets found in the sample.

Technical Abstract: Cellular lipid droplets are the least studied and least understood cellular organelles in eukaryotic and prokaryotic cells. Despite a broad research trying to understand lipid droplets it has not been possible to determine the composition of individual cellular lipid droplets. In this paper we present a novel approach based non-negative least-squares fitting of Raman spectra from single cellular lipid droplets to determine the composition of individual lipid droplets in cells after a treatment with different amounts of oleic and palmitic acid. By comparing the results from the single lipid droplet analysis to the results from gas chromatography analysis of millions of cells, we can show that proposed method can accurately predict the relative amount of a fatty acid in the lipid droplet, and that the composition in a single lipid droplet is on average the same as that of all lipid droplets found in the sample.