Description
Clinical relevance
Vitamin D (cholecalciferol) is a recognised clinical chemical determinant associated with osteoporosis and osteopenia (reduction in bone density). It also plays a role in the body's immune response, cardiovascular diseases and some types of cancer. Therefore, vitamin D is highly important from a number of diagnostic perspectives.
25-OH-vitamin D3 is the primary metabolite in the human body and the direct precursor of the physiologically active form 1.25-(OH)2-vitamin D3. First-line treatment for vitamin D deficiency is nutritional supplements with vitamin D3 or vitamin D2. Vitamin D2 is easier to synthesise and is widely used as a supplement outside of the EU, and especially in the United States. Therefore, its determination in serum/plasma is also relevant.
Product advantages
- Combined analysis of vitamins D2 and D3
- 100 µl sample volume is sufficient
- Selective online sample preparation
- Up to 100 samples per day
This Chromsystems kit allows simple and fast determination of 25-OH-Vitamin D3 and 25-OH-Vitamin D2 in a single HPLC run with UV detection. Following an efficient protein precipitation step, selective online solid phase extraction enables up to 100 analyses per day. Requiring only small sample volume, this analysis is also suitable for measuring paediatric samples. A stable internal standard ensures reliable quantification. This allows reproducible and reliable results while keeping costs and required laboratory time low.
Alternatively, there is also a standard method for HPLC (order no. 38038) as well as methods for determination using mass spectrometry (order no. 62000).
Content
Mobile Phase A (online method), 10 x 1000 ml
Mobile Phase B (online method), 10 x 1000 ml
Internal Standard (online method), 10 x 25 ml
25-OH-Vitamin D3/D2 Serum Calibration Standard (lyoph.), 2 x 2 ml
25-OH-Vitamin D3/D2 Serum Control, Level I, 2 x 2 ml
25-OH-Vitamin D3/D2 Serum Control, Level II, 2 x 2 ml
HPLC column, 1 pc.
Trap column, 1 pc.
PEEK-encased prefilter, 2 μm, 5 pcs.
Reaction vials, transparent, 100 pcs.
Technical Data
Method of Analysis
Number of Tests
Parameter
Analysis Time
Limit of quantification
Linearity
Recovery
Intraassay
25-OH-Vitamin D3: CV ≤ 3.2 %
25-OH-Vitamin D2: CV ≤ 4.1 %
Interassay
25-OH-Vitamin D3: CV ≤ 5.6 %
25-OH-Vitamin D2: CV ≤ 5.7 %
Information
The HPLC analysis of 25-OH-vitamin D3/D2 (online method) requires two HPLC pumps, a 6-port-valve and a UV detector.
Column temperature
Flow rate
Specimen
Sample Preparation
- Mix 100 µl serum/plasma with 250 µl Internal Standard in a reaction vial for 20 s (vortex).
- Cool down 10 min at +4 °C.
- Centrifuge 5 min at 15 000 x g.
- Inject 75 µl of the supernatant into the HPLC system.