Vitamin D is an important building block for human health, and has been linked in the literature to several clinically important diseases. Thus, it is necessary to provide physicians with accurate results to allow for confident assessment of Vitamin D sufficiency. With the SCIEX Vitamin D 200M Assay for the Topaz system, your lab can now harness the power of mass spectrometry to deliver accuracy without the complexity.
Master Challenging Assays with Gold Standard Technology
For many assays, mass spectrometry is considered the gold standard, delivering the specificity and sensitivity that other technologies lack. This enables clinical labs to deliver more confident results to clinicians to support quality patient care.
This is the case with our new SCIEX Topaz™ Vitamin D 200M Assay Kit, which delivers greater accuracy than other methods. Meeting the rigorous performance requirements, the SCIEX Topaz Vitamin 200M Assay has been certified by the CDC’s Vitamin D Standardization-Certification Program, and is the first LC-MS/MS Vitamin D assay cleared by FDA (via the de novo pathway). While individually quantitating the 25-hydroxyvitamin D2 and D3 metabolites of Vitamin D to provide an accurate total 25-hydroxyvitamin D, the Vitamin D 200M Assay Kit on the Topaz system provides separation from common interferents, such as 3-epi-25-hydroxyvitamin D, to deliver highly accurate diagnostic results in a single analysis.
Now a complete mass spec based assay solution for total Vitamin D exclusively for the Topaz system
SCIEX Vitamin D 200M Assay Kit for Topaz system
- FDA-cleared (via de novo pathway) Vitamin D 200M Assay Kit for the Topaz system
- Measures total 25-hydroxyvitamin D
- Pre-developed method to get up and running quickly
- Traceability to CDC + NIST standards produces accurate results
- Assay specificity ensured with interference testing on over 79 compounds (structurally similar, isobaric, and endogenous compounds)
- FDA-cleared assay reduces risk for laboratories over traditional lab developed tests
- Less than 1% bias to CDC reference method
- High sensitivity: LLMI of 4.1 ng/mL
Pinnacle of Diagnostic Accuracy
Plot showing method comparison data between the Vitamin D 200M Assay and the CDC reference method
Accuracy of 25-hydroxyvitamin D data from the Topaz system and Vitamin D 200M Assay Kit showed excellent correlation with the CDC reference method, exhibiting < 1% bias overall.
120 natural patient samples were evaluated for total 25-hydroxyvitamin D in parallel using the CDC reference method and the Topaz Vitamin D 200M assay.
The Topaz system with the Vitamin D Assay Kit provides highly accurate and specific quantitative measurements, even for similarly structured compounds in biological fluids.
The Topaz Vitamin D Assay removes interference from the 3-epi-25-hydroxyvitamin D3 epimer, preventing overestimation of total Vitamin D levels.
The Topaz Vitamin D Assay directly measures both 25-hydroxyvitamin D2 and D3 individually, to ensure accurate quantitation of total Vitamin D.
The method directly quantitates both 25-hydroxyvitamin D2 and 25-hydroxyvitamin D3; in addition, it separates out the 3-epi-25-hydroxyvitamin D3 epimer to removed biases seen with quantitation with other methods to deliver extremely accurate quantitation providing the specificity to deliver highly accurate diagnostic results in a single analysis.
Precision and Reproducibility
A 5-day precision study was performed at three sites and data was analyzed in accordance with CLSI guideline EP05-A3. The same set of samples were used at all the sites. Seven serum samples were used in this study with 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 concentrations approximating low (4.1 ng/mL) and high (90 ng/mL) assay levels.
The assay meets the repeatability (< 10% CV at all concentrations except for the lowest where is should be < 15%) and reproducibility (< 15% CV at all concentrations except for the lowest where is should be < 20%) goals. The maximum repeatability %CV estimate of all sample concentrations is 7.3% for 25-OH-vitamin D3, 6.6% for 25-hydroxyvitamin D3, and 6.3% for total 25-hydroxyvitamin D2. The maximum reproducibility %CV estimate of all sample concentrations is 9.8% for 25-hydroxyvitamin D3, 13.4% for 25-hydroxyvitamin D2, and 10.4% for total 25-hydroxyvitamin D. Summary data for all acquired instances is given above.
The reportable range comes from the linearity study (2.2-160 for D3, 1.9-165 for D2 and 4.1-325 for total Vitamin D. Since the lowest level in the linearity study was above the lowest level in the LLMI study, the actual LLMI values have to come from the linearity study (2.2 for D3, 1.9 for D2 and 4.1 for total.
|Analyte||LLMI (ng/mL)||Mean Signal-Noise Ratio|
|Total 25-OH-Vitamin D||4.1||n/a|
The signal-to-noise ratio at the LLMI for 25-hydroxyvitamin D3 and 25-hydroxyvitamin D2 using 90 determinations from 2 kit lots and 3 instruments exceeds the desired minimum value of 10. Summary data of the Limit of Detection investigations, including an example chromatogram at the LLMI, is shown above.