Influence of Microneedle Design on Variability in Dermal Interstitial Fluid Collection from Human Subjects

Youseong Kim – Postdoctoral Fellow, Chemical and Biomolecular Engineering, Georgia Institute of Technology; Isaree Pitaktong – Graduate Research Assistant, Biomedical Engineering, Georgia Institute of Technology; B. Pradeep K.Reddy – Postdoctoral Fellow, Georgia Institute of Technology; Erkan Azizoglu – Research Scientist II, Chemical and Biomolecular Engineering, Georgia Institute of Technology; Danial Hosseini – Graduate Research Assistant, Chemical and Biomolecular Engineering, Georgia Institute of Technology; Mark Prausnitz – Regents Professor, Chemical and Biomolecular Engineering, Georgia Institute of Technology

Introduction: Clinical diagnostics rely on disease-relevant biomarkers measured from patient biofluids to assess health status. Blood is the gold-standard sampling fluid, but dermal interstitial fluid (ISF) is a promising alternative because it shares key biomarkers and does not clot, facilitating measurements over time. Microneedles enable ISF extraction by creating skin pathways coupled with suction; however, collected volumes are often variable. This study evaluated how microneedle geometry affects the variability in ISF extraction volume during the collection process.