Application of a new volumetric microsampling device for quantitative bioanalysis of immunosuppression: Supplementary material

Background: Volumetric absorptive microsampling may reduce the blood collection burden associated

with therapeutic drug monitoring of immunosuppression to prevent organ transplant rejection. This

work describes the development of a laboratory and analytical technique for quantifying tacrolimus and

mycophenolic acid (MPA) from the Tasso-M20™ in human whole blood using bead-based impact-assisted

extraction. Results: The sampled blood volume was accurate with estimated volumes within <2% of the

expected 20 μl. Recovery using impact-assisted extraction was 73–87% for MPA and 100% for tacrolimus

and was hematocrit-independent for both analytes. The LC-MS/MS assay is precise and accurate within

the acceptance criteria of 15%. Conclusion: The sampling and extraction procedures allowed for accurate

quantification of tacrolimus and MPA. Exploration of abuse scenarios identified important education

points for patients conducting home-based sample collections in the future.