25羟维生素D 3 (骨化二醇）是一种激素原，通过维生素 D 3 (胆钙化醇）的羟基化作用在肝脏内产生。它是合成骨化三醇{1,25-二羟维生素 D 3 或称 [1,25(OH) 2 D 3 ]}的前体。它可用作生物标记物，用于确定体内维生素D的状态。 25-羟维生素D 3 -23,24,25,26,27- 13 C 5 是维生素 D 3 的同位素，其中的 C-23、C-24、C-25、 C-26和 C-27碳原子由 13 C 6 同位素所 应用 25羟维生素D 3 -23,24,25,26,27- 13 C 5 可用作稳定的同位素内标物，用于通过质谱得到特定生物样品的准确数据。 25-Hydroxyvitamin D 3 (calcifediol) is a prohormone produced via hydroxylation of vitamin D 3 (cholecalciferol) in the liver. It is a precursor for the synthesis of calcitriol {1,25-dihydroxyvitamin D 3 or [1,25(OH) 2 D 3 ]}. It is used as a biomarker to determine the status of vitamin D in the body. 25-Hydroxyvitamin D 3 -23,24,25,26,27- 13 C 5 is an isotope of vitamin D 3 wherein C-23, C-24, C-25, C-26, C-27 carbons are replaced by 13 C 6 isotope. Application 25-Hydroxyvitamin D 3 -23,24,25,26,27- 13 C 5 can be used as a stable isotope internal standard for data interpretation in specific biological samples by mass spectrometry.