| 25(OH)D3

25-hydroxycholecalciferol also known as Calcifediol or 25-hydroxyvitamin D3 (abbreviated 25(OH)D3),is a form of vitamin D produced in the liver by hydroxylation of vitamin D3 (cholecalciferol) by the enzyme vitamin D 25-hydroxylase.Calcifediol can be further hydroxylated by the enzyme 25(OH)D-1α-hydroxylase, primarily in the kidney, to form calcitriol (1,25-(OH)2D3), which is the active hormonal form of vitamin D.Calcifediol is strongly bound in blood by the vitamin D-binding protein.Measurement of serum calcifediol is the usual test performed to determine a person's vitamin D status, to show vitamin D deficiency or sufficiency.
 

| Typical data

As the OD values of the standard curve may vary according to the conditions of the actual assay performance (e.g. operator, pipetting technique, wash technique or temperature effects), the operator should establish a standard curve for each test. Typical standard curve and data are provided below for reference only.

 

Concentration (ng/mL)	50	25	12.5	6.25	3.12	1.56	0.78	0
OD	0.14	0.24	0.37	0.62	0.90	1.21	1.66	1.88

 

| Repeatability

Intra-assay Precision (Precision within an assay)：CV% < 10%; Inter-assay Precision (Precision between assays)：CV% < 10%
 

| Recovery

The recovery of 25(OH)D3 spiked at three different levels in samples throughout the range of the assay was evaluated in various matrices.

 

Sample Type	Range(%)	Average Recovery(%)
Serum(n=8)	87-114	99
Plasma(n=8)	83-110	94

 

| Linearity

Samples were spiked with high concentrations of 25(OH)D3 and diluted with Universal Diluent to produce samples with values within the range of the assay.

 

		Serum(n=4)	Plasma(n=4)
1 : 2	Range (%)	87-113	86-106
	Average (%)	101	98
1 : 4	Range (%)	88-112	83-114
	Average (%)	100	104