Rapid Analysis of C3 Epimers of 25-Hydroxyvitamin D in Serum by LC-MS/MS

Author: Shun-Hsin Liang, Frances Carroll

Restek Corporation

Published By: Restek Corporation

Year of Publication: 2017

Link: http://www.restek.com/Technical-Resources/Technical-Library/Clinical-Forensic-Toxicology/cft_CFAN2612-UNV


The C3 epimers of 25-hydroxyvitamin D have lower bioactivity than the primary metabolites and, unless they are chromatographically separated, can cause clinical vitamin D levels to be overestimated. Raptor FluoroPhenyl columns provide baseline resolution of all key compounds, and the method established here allows accurate quantification in a fast, 5-minute analysis time (7-minute total cycle time). This method is recommended for labs interested in reporting C3 epimer concentrations separately in order to obtain more accurate results for the clinical diagnosis of vitamin D status.

Restek and Skills of Central PA Offer Career Training to High Schoolers with Disabilities

This preemployment program helps students learn skills and explore options so they can find rewarding work after graduation.

Curtis Clouser and Maren Dotoli at Restek’s Founder’s Point fitness facility.

Curtis Clouser loves his job at Restek — the chromatography supplies manufacturer in Bellefonte, PA.

For a half day, three days a week, he leaves Bellefonte High School, where he is a senior, to help keep Restek’s employee wellness center clean and tidy by wiping down all the equipment, cleaning the windows and mirrors, and folding towels. For a young man with disabilities, an opportunity like this is incredibly important for getting a job and helping support himself after graduation.

Curtis is the third student to cycle through Restek from this new preemployment program offered through Skills of Central PA, a nonprofit pioneer in developing comprehensive, community-based programs and services for people with disabilities.

Mike Perlozzo, the wellness coordinator at Restek, said the program is a win-win.

“The program benefits both parties because with him cleaning, we can focus on other things we have to get done during the day,” he said.
Maren Dotoli, a job coach for Skills who works with Curtis when he goes to Restek, said he loves having the responsibility.

“He loves having a job and making money and talks about having a pizza party when he’s finished,” she said. “It’s great to see that enthusiasm and it’s honestly the best part of my job.”

Currently, Skills works with eight students with disabilities from Centre County thanks to a grant from the state’s Office of Vocational Rehab (OVR). The students are paid for 90 hours of work at one location and then transferred to another location to maximize exposure to available options. Elizabeth Koch, a manager at Skills, said any time you can get high school students with disabilities out into the real world, they can better identify what kind of work they prefer to do and are good at.

“Our primary goal is to improve the lives of people with special needs by focusing on their abilities,” she said. “And with this program, we get to see what their skills are so we can help place them in a job they will love after they graduate.”

While Restek and Skills have only been working on this program for a little more than three months, their relationship goes back decades. For more than 20 years, Restek has relied on a partnership with Skills’ industry services warehouse, where adults with disabilities assist with the final assembly of many Restek products.

To learn more about Skills of Central PA, visit http://www.skillsofcentralpa.org 

Single-Compound Standards from Restek Improve the Analysis of Difficult Pesticides

Tractor spraying a field at sunset

Troublesome pesticides can be analyzed more easily and accurately with single-compound standards from Restek. New individual standards are now available for dicofol, metribuzin, bromacil, lenacil, dodine, anilazine, captan, and folpet. Use these standards to simplify method development, establish instrument detection limits (IDLs), verify performance, test stability, and resolve degradation issues. Restek is your one-stop shop for accurate, reliable pesticides analysis. We are the only reference standard provider that offers everything you need from sample prep to LC and GC columns and consumables.


Analyze CO and CO2 at ppb Levels Easily and Accurately with a Restek Methanizer

Low-level detection of carbon monoxide (CO) and carbon dioxide (CO2) is critical for many applications. Restek’s methanizer (CH4izer) for Agilent GCs allows ppb-level determination of CO and CO2 using a cost-effective FID instead of more expensive instrumentation. The methanizer is factory set to 380 °C to ensure efficient and complete conversion of CO and CO2 to CH4, but the operator can easily adjust the temperature as desired with the touch of a button. This unit controls temperatures precisely and reliably to within ± 1 °C of the defined set point and the actual temperature is shown in real time on an easy-to-read display. The Restek methanizer is less cumbersome than other models and is designed for easy installation and fast catalyst tube replacement so you spend more time analyzing samples and less time on maintenance.

Get complete product details at www.restek.com/CH4izer