Quantitation of BCAA and BCKA in plasma and patient-centric dried blood microsamples in a clinical setting.

Aim: This study assessed the agreement and bias of three dried blood patient-centric microsampling (PCS) devices (paper DBS, Mitra, and Tasso-M20) for the quantitation of branched chain amino acids (BCAAs) and ketoacids (BCKAs) compared to venous plasma samples.

Materials & methods: Concentrations of BCAAs and BCKAs were measured in samples from generally healthy participants with a validated assay for venous plasma adapted for use with dried blood from the PCS devices. Participants were also asked to respond to a device usability questionnaire about their experience with the devices.

Results: The correlations between BCAA/BCKA concentration values in PCS devices vs venipuncture samples were strong to excellent for all six analytes, across all three PCS devices. The surrogate analyte approach facilitated method transfer from plasma to dried blood microsampling devices. Overall, participants reported that they enjoyed using the devices compared to traditional venipuncture and would be willing to use them again, on their own at-home.

Conclusion: These study results demonstrate the feasibility of quantitating BCAAs and BCKAs reliably with PCS devices, with high acceptability from study participants.