Precision metering and autonomous separation of blood components for pre-clinical microsampling at the point-of-care

PROJECT SUMMARY/ABSTRACT Liquid venous blood is the gold standard for the majority of clinical assays, but it is unrealistic to expect it can be collected at home or in remote locations due to the need for trained phlebotomists and the costs and logistics related to cold chain transport. Approaches that enable patient-centric microsampling—where blood that is self- collected by fingerstick can be sent ambiently through the mail—have the potential to address challenges with specimen transport. However, the development of these technologies, typified by the century-old dried blood spot (DBS) card, has not kept pace with the clinical need or emerging capabilities of telemedicine. The ability to maximize the diagnostic test menu available to patients fundamentally relies on the successful transport of dried blood or plasma to clinical laboratories. To make reliable clinical decisions, enable diagnoses, and inform treatment decisions, there is an outstanding need for functional patient-centric devices that stabilize specimens and enable measurements that are consistent with venous blood. Any solution must support two unique sets of users: (i) Patients who desire access to routine tests for chronic conditions that would otherwise require them to travel to receive care, and tests that provide personalized insight into their health status. (ii) Laboratories that require high quality samples that do not introduce unpredictable sources of error into the quantitative measurements that will be used to inform healthcare decisions, and processes that do not disrupt their current analytical workflows. Previously, we demonstrated that patterning DBS cardstocks can create metered collection zones for microsampled dried blood and plasma that support measurements of a wide range of analytes that are equivalent to those made using liquid blood. Using our expertise in paper microfluidic devices, we propose the development of paper-based microsampling devices that are designed to further close the gap between current laboratory testing capabilities and ongoing patient needs by providing stable and metered samples of dried blood and plasma to existing clinical workflows. Innovations in patient-centric, microsampling technologies will reduce global disparities to access in healthcare, provide increased agency to patients desiring more information about their health status, and support ongoing advances in telemedicine. We anticipate that the capabilities demonstrated by our patterned dried blood and dried plasma spot cards will serve these needs and facilitate improvements in patient care.