The test is the first quantitative test on the firm's flagship Sofia immunoassay platform.
Since introducing new clinical platforms last year, Sciex has launched an automated sample prep system while Thermo Fisher has begun customer beta testing.
The company's revenue growth resulted from acquisitions, but Quest faced headwinds from PAMA pricing and reductions in hepatitis C genotyping and vitamin D testing.
In the last year, both Sciex and Thermo Fisher have launched clinical platforms, but whether they will prove commercial successes remains to be seen.
Diazyme's managing director said that the assay enables clinical labs "of almost any size" to run a vitamin D test in house without specialized instruments.
The company is targeting hospital labs interested in a more streamlined mass spec solution as the clinical mass spec market begins to heat up.