2010/08/17 by Thuc T. Le, Shuhua Yue, Ji-Xin Cheng +1
Biochemistry, Genetics and Molecular Biology · Agricultural and Biological Sciences · #Spectroscopy Techniques in Biomedical and Chemical Research #Bee Products Chemical Analysis #Advanced Fluorescence Microscopy Techniques
paper · pdf · doi:10.1194/jlr.r008730
Despite the ubiquitous roles of lipids in biology, the detection of lipids has relied on invasive techniques and population measurements. The molecular profi les of the lipid-rich structures are evaluated by measurements of total lipid extracts with liquid or gas chromatography coupled to mass spectrometry ( 8 ). This approach is inexact because it measures lipid molecules from areas other than the structures of interest. Furthermore, spatial information, which is critical to understanding the function of lipids ( To visualize the lipid-rich structures, fl uorescently tagged lipid molecules, which intercalate with the lipidrich structures, are used ( 10, 11 ). Nevertheless, the use of the fl uorescent lipid molecules to label lipid-rich structures is problematic for several reasons. First, to facilitate the transport of the fl uorescent lipid molecules into cells, cell fi xation procedures are often performed ( 12 ). This procedure prevents monitoring the dynamic responses of lipid-rich structures to stimuli or the disease processes. Second, labeling effi ciency is highly dependent on the type of fl uorescent lipid molecules ( 12 ), thus posing a signifi cant problem to the quantitation of lipid-rich structures. Third, the intercalation of fl uorescent lipid molecules can lead to changes in the properties of lipidrich structures. For instance, incorporation of fl uorescent lipid molecules into the cell membrane can induce membrane phase separation and membrane microdomain formation, which can perturb critical cellular processes including signal transduction and endocytosis ( 13 ).