Scientists at United Arab Emirates University (UAEU) are working on a new blood test to detect levels of vitamin D in humans.
Part of a wider project into vitamin D deficiency in UAE, the lead scientist, Dr. Iltaf Shah, an Assistant Professor of Biochemistry at UAEU, says the new blood test will help give more accurate results when it comes to measuring vitamin D levels in people across the country.
“Vitamin D tests are currently carried out by taking a blood sample in UAE,” explains Dr. Shah. “Vitamin D exists in our blood in at least 10 different forms. But the current test for vitamin D available in hospitals is the total 25-hydroxyvitamin D test (composed of D2 and D3 forms); and mostly enzyme-linked immunoassay (ELISA) methods are used to carry out this test. Recent research shows that ELISA tests cannot distinguish between D3 and D2 content removed forms of vitamin D, with different suggested biological activities.”
While recent developments in liquid chromatography-mass spectrometry – an analytical chemistry technique – have made it possible to distinguish between D3 and D2 forms, along with an increase in sensitivity and reduced volume of blood sample, this can also show false optimum levels of vitamin D results because they do not take into account epimers and isobars of vitamin D that can account for a significant proportion of total circulating vitamin D.
“As a result, this can compromise the measurement and interpretation of vitamin D status,” adds Dr. Shah. “We analyze 10 different metabolites of vitamin D to look at the whole picture after separating the epimers and isobars – which are giving false positives. Epimers and isobars have exactly the same mass as the 25-hydroxy forms and they add up to the 25 hydroxyvitamin D estimated value.
“The new method is sensitive, selective and accurate and it is efficient in extraction and chromatographic separation. The method is capable of accounting for the misleading measures due to the epimers and isobars. The results demonstrate the feasibility of applying the assay in research and clinical practice and to facilitate further in vivo investigation into the role of ubiquitous epimers.”
Having successfully secured a grant from the UAEU, Shah, who joined UAEU from Kingston University London in 2014, is now waiting on a new piece of equipment to further his research: a liquid chromatography mass spectrometry to further improve on this test.
The project comes after Dr. Shah developed an alternative vitamin D test to help doctors accurately measure the active forms of vitamin D in patients.
“Despite the availability of sunshine in the UAE, the UAE has high prevalence of vitamin D deficiency – about 80 percent of the UAE population has vitamin D deficiency, which is highly prevalent in Emirati women,” says Dr. Shah. “And while the test we have developed is not in the hospitals yet, we want it to be implemented in all the hospitals in the UAE so people can get the right results for their samples. If we want to save people from serious diseases then this test should be implemented.
“This new method holds promise for the improvement of current vitamin D analytical methods, and for the further development of in vivo research looking into the role of different vitamin D epimers,” he concludes.