Radioimmunoassays pantothenic acid

There are no convenient or reliable functional tests of pantothenic acid status, thus assessment is made by direct measurement of whole blood or urine pantothenic acid concentrations. Urine measurements are perhaps the easiest to conduct and interpret, and concentrations are closely related to dietary intake, Whole blood measurements are preferred to plasma, which contains only free pantothenic acid and is insensitive to changes in pantothenic acid intake. Concentrations of pantothenic acid in aU of the above fluids can be measured by microbiological assay, most commonly using Lactobacillus plantarum. Whole blood must first be treated with an enzyme preparation to release pantothenic acid fi om CoA. Other techniques that have been used to measure pantothenic acid in human samples include radioimmunoassay and gas chromatography, Other techniques that have been developed include gas chromatography-mass spectrometry and a stable isotope dilution assay. CoA and AGP can be measured by enzymatic methods. ... 

Wyse BW, Wittwer C, Hansen RG. Radioimmunoassay for pantothenic acid in blood and other tissues. Clin Chem 1979 25 108-10. 

Radioimmunoassay has been used for assay of pantothenic acid in physiological samples (sensitivity 250 nmol 1 ), and an enzyme-linked immunosorbent assay (ELISA) has been used for this vitamin in food analysis. 

Radioimmunoassay (RIA) and enzyme-linked immunosorbent assay (ELISA) procedures are no longer used for pantothenic acid determination because no commercially available antibody is available for these techniques. 

Pantothenic acid and pantetheine may be assayed using several enzymatic tests with pantothenase (40). Immunoassays and, especially, radioimmunoassays have been used in the analysis of pantothenic acid in tissue fluids, because of their sensitivity, specificity, and high rates of sample throughput. The radioimmunoassay (RIA) methods have about the same sensitivity as microbiological tests (approximately 0.05 pg/mL). As an alternative to the radioimmunoassay, the enzyme-linked immunosorbent assay (ELISA) is particularly suitable for the routine analysis of foods (41-45). 

Concentrations in body fluids are traditionally measured by microbiological assay using Lactobacillus plantarum. If CoA is present, enzymatic hydrolysis is needed to liberate free pantothenic acid for the microbiological assay. Other assay methods reported include gas chromatography (after conversion to a volatile derivative), radioimmunoassay (RIA), or enzyme-linked immunoabsorbent assay (ELISA). 

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