Extractability-mediated stability bias and hematocrit impact: High extraction recovery is critical to feasibility of volumetric adsorptive microsampling (VAMS) in regulated bioanalysis

In lung and renal transplant recipients, VAMS sampling with LC-MS/MS quantification of mycophenolic acid and tacrolimus showed good linearity and accuracy, and with a haematocrit-adjusted conversion formula achieved clinical agreement in most samples; tacrolimus did not require haematocrit correction. The approach is virtually painless and enables richer sampling for more accurate drug exposure estimates, supporting decentralised therapeutic drug monitoring.

Evaluation of hematocrit-adjusted conversion strategies for mycophenolic acid and tacrolimus monitoring using volumetric absorptive microsampling in lung and renal transplant recipients — Juan et al., Journal of pharmacy & pharmaceutical sciences : a publication of the Canadian Society for Pharmaceutical Sciences, Societe canadienne des sciences pharmaceutiques · source ↗

• blood
• dried
• vams
• neoteryx-mitra
• validation
• venous-agreement
• tdm
• immunosuppressants
• haematocrit

This review found that volumetric microsampling devices, such as Mitra, HemaPEN, HemaXis DB10, and Tasso-M20, overcome haematocrit bias, whilst Telimmune plasma separation cards enable direct plasma collection without centrifugation. These technologies support patient-centric, decentralised sampling, though the authors note that clinical validation remains limited across different drugs and patient populations.

A Review of Blood-Based Microsampling Devices for Patient-Centered Application in Therapeutic Drug Monitoring — Huhn & Scherf-Clavel, Therapeutic drug monitoring (paywalled) · source ↗

• vams
• volumetric
• acceptability
• neoteryx-mitra
• blood
• dbs
• tdm
• self-collection
• haematocrit
• dried
• capillary
• validation

The study validated an LC-MS/MS method for eight antiepileptic drugs and two metabolites in dried blood spot and VAMS formats, with satisfactory analytical performance and stability, and was the first to include the oxcarbazepine metabolite DHCB. In 80 paired patient samples, microsampling concentrations showed promising correlation with plasma, supporting decentralised therapeutic drug monitoring of antiepileptic treatment.

Development and application of an LC-MS/MS method for 8 antiepileptic drugs and 2 metabolites using microsampling techniques (DBS and VAMS) — Cobo-Golpe et al., Journal of analytical toxicology · source ↗

• blood
• dried
• vams
• dbs
• neoteryx-mitra
• validation
• venous-agreement
• tdm
• haematocrit

The study developed and validated a rapid LC-MS/MS method for quantifying cefazolin in capillary whole blood collected via VAMS, plasma, and plasma ultrafiltrate, showing robust performance across matrices and successful application in a pediatric pilot cohort for therapeutic drug monitoring.

Rapid, robust LC-MS/MS quantification of cefazolin in whole blood microsamples, plasma, and plasma ultrafiltrate: Analytical method validation and preliminary clinical application in pediatric population — Kocur et al., Clinica chimica acta; international journal of clinical chemistry (paywalled) · source ↗

• vams
• neoteryx-mitra
• blood
• tdm
• haematocrit
• dried
• antimicrobials
• capillary
• pediatric
• validation

This study demonstrates that a commercial conductive vial electromembrane extraction device can reliably isolate basic pharmaceuticals from whole blood collected on volumetric absorptive microsampling tips, showing superior reproducibility and reduced matrix effects compared to conventional treatment.

Volumetric absorptive microsampling and conductive vial electromembrane extraction for the analysis of pharmaceuticals in whole blood — Reguli et al., Talanta (paywalled) · source ↗

• blood
• dried
• vams
• neoteryx-mitra
• validation
• tdm
• haematocrit