Location: Food Components and Health LaboratoryTitle: Separation of lipoproteins for quantitative analysis of 14C-labeled lipid soluble compounds
|CHUANG, JENNIFER - University Of California|
|CLIFFORD, ANDREW - University Of California|
|HOSTEGE, DIRK - University Of California|
|SEUNG-HYUNG, KIM - Konkuk University|
|FADEL, JAMES - University Of California|
|KELLY, PETER - University Of California|
|WALZEM, ROSEMARY - Texas A&M University|
Submitted to: Analytical Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 8/20/2015
Publication Date: N/A
Interpretive Summary: Isotopes are forms of the same chemical element that are distinguishable from one another. Use of isotopes has allowed nutrition scientists to tag vitamins, minerals, and other dietary components to follow their metabolism through the body. Dietary components that are oily in character (for example, fat soluble vitamins like vitamin E) move through the blood stream traveling on lipoprotein particles. There are several different types of lipoprotein particles in the blood, and full understanding of metabolism requires scientists to track the dietary components’ movement on these different particles. We have developed a new method to follow nutrients as they move through the lipoprotein particles. The previous method of separating different lipoprotein particles in the blood was very time consuming and took several days to complete. The new method allows separation of these different blood fractions in a few hours. This is a major breakthrough because metabolic studies require collection of many blood samples over time, making the longer 3-day method too difficult when collecting such a large number of samples. This information will be used by scientists.
Technical Abstract: Carbon-14 tracer studies using accelerator mass spectrometry (AMS) have provided novel insights into nutrient metabolism and whole body metabolite flux. In addition to a baseline separation of analytes, a critical requirement specific to the AMS analysis was a stable carbon baseline within the analyte matrix. Continuous density gradient ultracentrifugation provides the means to separate lipid-soluble analytes within physiologically relevant lipoprotein complexes. Recent advancements in separation media allow for procedural improvements such as reduced separation time in conjunction with enhanced resolution and imaging of achieved separations and make this an attractive method for AMS studies. Separation media and conditions, sample collection and desalting procedures were optimized for AMS tracer studies of lipid-soluble nutrient kinetic modeling.