Clinical Laboratory Case Study

Dried Blood Spot Analysis for Vitamin B6 and B9

Project Overview:

Dried blood spot analysis often puts a strain on assay sensitivity due to limited sample volume. In order to achieve necessary cutoffs, laboratories are forced to inject large volumes onto the LC-MS/MS system, often compromising the integrity of the LC column. A clinical laboratory was looking to develop a method for the quantitation of Vitamin B6 and B9 from 9 mm punches of a serum separator card and faced similar challenges.


Kevin looked for sample preparation that was easy to implement. After solubilizing the serum from the punch in aqueous buffer and protein precipitated with PCA, Kevin employed Dual Phase Filtration tips to filter the solution prior to injection for analysis of Vitamin B6 and B9. “The Tip-on-Tip extraction performed using DPX Dual Phase Filtration Tips allows us to achieve the sensitivity we need, while providing a cleaner sample for our mass spec.”

"Solid Phase Extraction used to be scary terminology in the laboratory industry because it indicated the need for complex sample preparation performed with expensive equipment. Now it's as simple as pipetting with a DPX filtration tip, and we can easily achieve improved sensitivity through their updated sample preparation techniques."
Kevin Davis – Laboratory Consultant, Research and Development of LC-MS Assays

About this Laboratory:

This clinical lab has a menu of over 400 chemistry, hematology, molecular, immunoassay, allergy, and toxicology tests. They perform research and development for specialty validations and processing non-traditional / micro samples, such as blood spot or serum separator cards.