High-Yield Passive Plasma Filtration from Human Finger Prick Blood

Abstract

Whole-blood microsampling provides many benefits such as remote, patient-centric, and minimally invasive sampling. However, blood plasma, and not whole blood, is the prevailing matrix in clinical laboratory investigations. The challenge with plasma microsampling is to extract plasma volumes large enough to reliably detect low-concentration analytes from a small finger prick sample. Here we introduce a passive plasma filtration device that provides a high extraction yield of 65%, filtering 18 μL of plasma from 50 μL of undiluted human whole blood (hematocrit 45%) within less than 10 min. The enabling design element is a wedge-shaped connection between the blood filter and the hydrophilic bottom surface of a capillary channel. Using finger prick and venous blood samples from more than 10 healthy volunteers, we examined the filtration kinetics of the device over a hematocrit range of 35−55% and showed that 73 ± 8% of the total protein content was successfully recovered after filtration. The presented plasma filtration device tackles a major challenge toward patient-centric blood microsampling by providing highyield plasma filtration, potentially allowing reliable detection of low-concentration analytes from a blood microsample.

A microfluidic device for TEM sample preparation

“…The devices were fabricated using lamination technology where the device is formed by stacking several layers of different materials, as described previously. 17,18 The cross section in Fig. 1a shows the different layers.…”

“…The PVA film was fabricated, as previously reported, 17,18 from an aqueous solution of 20 wt% of granular PVA. Using a thin-film applicator (4340, Elcometer, Manchester, UK) the PVA films were uniformly transferred to laminating pouches (3385694, Office Depot, LA Venlo, Netherlands) and dried at room temperature.…”

Dried Blood Spot Self‐Sampling with Automated Capillary Electrophoresis Processing for Clinical Analysis

“…To obtain blood samples, the presence of the investigated subjects/patients in clinical laboratories is required, which is time‐consuming for both the subjects/patients and the laboratory staff, and usually involves painful venous phlebotomy. The above‐mentioned shortcomings have led to recent developments in the field of patient‐centric microsampling that can provide a wide range of benefits including less painful/disruptive blood sampling methods [2–4] . It involves self‐sampling of a microliter volume of capillary blood, which is withdrawn from a finger prick and forms a dried blood spot (DBS) [3, 4] .…”

Design and Characterization of a Novel Blood Collection and Transportation Device for Proteomic Applications

“…To minimize issues with blood hematocrit, volumetric collection of whole blood followed by analysis of the entire sample has been demonstrated to be effective [13,14]. In addition, devices have been developed that separate the "plasma-like" fraction from whole blood without the need for centrifugation [15][16][17]. Since these devices separate the Red Blood Cells (RBCs) through filtration, the analyte concentration could be altered when compared to plasma generated with centrifugation.…”