U.S. flagAn official website of the United States government
                    Here's how you know **Official websites use .gov**
                            
                            A **.gov** website belongs to an official government organization in the United States.
 **Secure .gov websites use HTTPS**
                            
                            A **lock** (                            
                              A locked padlock                                                      
                            
                            ) or **https://** means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.


Menu Agricultural Research Service
						
                    U.S. DEPARTMENT OF AGRICULTURE
 close



Research
                Research Home
                            National Programs
                            Research Projects
                            Scientific Manuscripts
                            International Engagement
                            Scientific Software/Models
                            Databases and Datasets
                            Office of Scientific Quality Review
            Media
                News & Features
                            Multimedia
                            Briefing Room
                            Down on the Farm
                            Press Room
                            Science in Your Shopping Cart
                            Scientific Discoveries
                            Tellus
                            Under the Microscope
            About ARS
                About ARS Home
                            Staff Directory
                            Labs and Research Centers (Map)
                            Headquarter Offices
                            Organizational Chart
                            Employee Services (REE Employees Only)
                            Office of Outreach, Diversity, and Equal Opportunity
            Work With Us
                Work With Us Home
                            ARS Vacancies at USAJOBS
                            Careers at ARS Information
                            Scientific Collaborations
                            Extramural Agreements
                            1890 Faculty Research Sabbatical ProgramSearch small
                    Search
            
            ARS Home
                                About ARS
                                Contact Us




ARS Home News & Events News Articles Research News 2013





- ARS News & Events
- AgResearch Magazine
- Image Gallery
- News
- Search News & Events
- Pesticide Drift May Endanger Pollinators
- ARS Seeks a Fire Ant Fix
- Scientific Discoveries 2024
- ARS Featured Photos
- Down on the Farm
- Facebook Live Events
- Food and Nutrition Research Briefs
- News Archive
- Science in Your Shopping Cart
- Scientific Discoveries
- Social Media
- Under the Microscope
- AgResearch magazine
- ARS at Work
- ARS Memorial Lectures
- ARS Science Hall of Fame
- Citrus Disease (Huanglongbing)
- Contact Office of Communications
- Plant Hardiness Zone Map
- Mobile Apps
- Public Affairs Contacts
- Publications and Other Resources
- USDA Blog
- Videos

Archived Page
 This page has been archived and is being provided for reference purposes only. The page is no longer being updated, and therefore, links on the page may be invalid.
 **Read the magazine story to find out more.**A new vitamin B12 assay developed by ARS scientists requires only a tiny drop of blood. Click the image for more information about it.Listen to podcast.For further readingResearchers analyze metabolites in bloodPotential Indicators of type 2 diabetes investigatedLuteolin stars in study of healthful plant compounds Improved Vitamin B12 Test May Help Young and Old Alike By Marcia Wood  April 22, 2013 In the United States, the very young and the elderly are among the groups at risk of becoming deficient in vitamin B12, an essential nutrient. Now, a team of U.S. Department of Agriculture (USDA) scientists led by research chemist John W. Newman has developed and tested an improved method for measuring an indicator of the body's stores of B12 in blood. Importantly, the blood sample can be very small in volume. That's an advantage in both medical and research situations. Blood samples that are taken from newborns and infants—for health exams at a hospital, or perhaps for use by medical or nutrition researchers—are typically very small. In addition, a small amount of sample is often the norm in complex, large-scale studies in which blood samples from volunteers have to be allocated among many researchers, each of whom may need it for a different research purpose. Newman and his colleagues have shown that a specimen of only 25 microliters of blood plasma or serum—the equivalent of about one-half of a drop of water—can be analyzed with speed, accuracy, reliability and precision using an analytical technology called UPLC-ESI-MS/MS (ultra-performance liquid chromatography-electrospray ionization-tandem mass spectrometry). If the assay is performed using robotics, the sample could perhaps be as small as 5 microliters, according to Newman. His team built upon earlier work in which scientists elsewhere used an older technology to measure the same indicator compound that Newman's group selected, namely, MMA (methylmalonic acid). MMA can build up in the bloodstream if there isn't enough vitamin B12 in the body. The 25-microliter sample size needed for the new MMA assay represents a 4- to 10-fold reduction in the volume of specimen required for other MMA-based B12 tests. Samples take only about four minutes to process, according to Newman, who works at the Agricultural Research Service (ARS) Western Human Nutrition Research Center in Davis, Calif. ARS is the chief intramural scientific research agency of USDA, and the B12 research supports the USDA priority of improving children's health and nutrition. In developing the assay, Newman collaborated with Lindsay H. Allen, director of the ARS research center, and with three other ARS colleagues: chemist Theresa L. Pedersen, physical scientist William R. Keyes, and nutritionist Setareh Shahab-Ferdows. The team documented the research in a peer-reviewed article published in 2011 in the *Journal of Chromatography B*. Read more about this research in the April 2013 issue of *Agricultural Research* magazine.


Return to top


Research
                            Media
                            About ARS
                            Work With Us


Connect with ARS Sign up


ARS Home
                            USDA.gov
                            Plain Writing
                            Policies & Links
                            Civil Rights Statements
                            FOIA
                            Accessibility Statement
                            Privacy Policy
                            Non-Discrimination Statement
                            Quality of Information
                            USA.gov
                            WhiteHouse.gov