1. Microsampling Toolsfor Quantitative Dried Matrix SpottingCPSA 2012October 3rd, 2011Presented byDrummond Scientific Company

2. Microsampling (less is more) Increased attention to 3Rs:(replacement, reduction and refinement) Improved detection limits Efficiency(sample less - utilize more) 3. Drummond NichePrecision Liquid TransferMicrosampling for Dried Matrix Spotting (DMS)Accurate and Precise DMS Volumes 4. Is DMS spot volume important? Hematocrit Effect? - punching a fixed-area disk from within the DMSspot may not assure consistent normalized sampling One possible solution Whole Spot Approach But need to limit the spot size - e.g., 5uL - 15uL Reasonable degree of sampling accuracy and precisionWhat microsampling tools are fit-for-purpose? 5. Drummond Positive Displacement Capillary Pipet Polyester wrappedCapillary can be treated for safety internally with anticoagulant Proprietary Plugcontrols sample uptakePlunger advances plug which purges sample fromwalls of tube Complete sample transfer 6. Drummond DBS Multi-dispenser Prototyping 3x15uL, 4x10uL, and 5x5uLmulti-dispensersPlugged Capillary PipetPlunger [1] Insert capillaryhereDispenser Handle[2] Depress (and release) plunger to [3] Ejector Ring grasp and pull toward Dispense multiple aliquotshandle to release spent capillary tube and to reset dispenser for next use 7. Drummond Plasma Separation Capillary plasma separation from a single tube Separator gelPlug/seal Plug seals when bloodcome in contactSeparator gel CENTRIFUGEPlasmaSeparator Gel RBCs 8. Findings Positive displacement capillary pipets and multi-dispensers are easyto use for sample collection and dispensing(In the lab great. In the field further refinements) These devices deliver spotting precision (CV=1.5 3.5%) formicrosamples of 10-15uL. (Currently evaluating 5uL) Touching the capillary tip to DMS card surface (controversial?) yields: more complete sample transfer significantly better spot consistency (CV = 1.5 1.8%) 9. Future Directions Further studies to improve the design, accuracy, and precision ofpositive displacement capillary pipets and multi-dispensers for DMS Drummond is investigating microsampling tools for field/P-O-CapplicationsYour ideas and feedback are welcomed. Thank You! 10. AcknowledgementsAcknowledgements Mike LeeMilestone Development ServicesOrganizing Committee, Sponsors and Attendees of2012 CPSA USA