A novel approach to capillary plasma microsampling for quantitative bioanalysis.

Area of Science:

• Biomedical Engineering
• Pharmacokinetics
• Laboratory Medicine

Background:

• A novel device and procedure for collecting and isolating microvolumes of plasma have been developed.
• Two pilot rodent pharmacokinetic (PK) studies utilizing this new method have been successfully completed.

Purpose of the Study:

• To introduce and validate a new technique for efficient plasma sample collection in rodent studies.
• To demonstrate the utility of the developed device and procedure for toxicokinetic (TK) assessments.

Main Methods:

• Blood is collected into a plastic-wrapped, EDTA-coated capillary tube containing a thixotropic gel and a porous plug.
• The capillary tube is centrifuged in a secondary container, allowing the gel to isolate plasma from red blood cells.
• Generated plasma is then dispensed from the capillary tube for storage or further processing.

Main Results:

• The thixotropic gel effectively separates plasma from red blood cells during centrifugation.
• A physical barrier is created, preventing matrix contamination and ensuring plasma integrity.
• The method allows for the collection and isolation of small plasma volumes suitable for rodent studies.

Conclusions:

• A simple, robust, and novel approach for collecting small plasma volumes from rodent TK studies has been demonstrated.
• This method provides a reliable means for obtaining plasma samples, crucial for PK and TK analyses.