Application of a new volumetric microsampling device for quantitative bioanalysis of immunosuppression

Bioanalysis. 2022 Sep;14(17):1141-1152. doi: 10.4155/bio-2022-0155. Epub 2022 Oct 8.


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.

Keywords: Tasso-M20; immunosuppression; impact-assisted extraction; method validation; quantification; volumetric absorptive microsampling.

MeSH terms

  • Blood Specimen Collection / methods
  • Chromatography, Liquid / methods
  • Dried Blood Spot Testing
  • Hematocrit / methods
  • Humans
  • Immunosuppression Therapy
  • Mycophenolic Acid
  • Tacrolimus*
  • Tandem Mass Spectrometry* / methods


  • Tacrolimus
  • Mycophenolic Acid