Validation of Paper-Based Assay for Rapid Blood Typing

Abstract

We developed and validated a new paper-based assay for the detection of human blood type. Our method involves spotting a 3 μL blood sample on a paper surface where grouping antibodies have already been introduced. A thin film chromatograph tank was used to chromatographically elute the blood spot with 0.9% NaCl buffer for 10 min by capillary absorption. Agglutinated red blood cells (RBCs) were fixed on the paper substrate, resulting in a high optical density of the spot, with no visual trace in the buffer wicking path. Conversely, nonagglutinated RBCs could easily be eluted by the buffer and had low optical density of the spot and clearly visible trace of RBCs in the buffer wicking path. Different paper substrates had comparable ability to fix agglutinated blood, while a more porous substrate like Kleenex paper had enhanced ability to elute nonagglutinated blood. Using optimized conditions, a rapid assay for detection of blood groups was developed by spotting blood to antibodies absorbed to paper and eluted with 200 μL of 0.9% NaCl buffer directly by pipetting. RBCs fixation on paper accurately detected blood groups (ABO and RhD) using ascending buffer for 10 min or using a rapid elution step in 100/100 blood samples including 4 weak AB and 4 weak RhD samples. The assay has excellent reproducibility where the same blood group was obtained in 26 samples assessed in 2 different days. Agglutinated blood fixation on porous paper substrate provides a new, simple, and sensitive assay for rapid detection of blood group for point-of-care applications.

Qualitative and quantitative detection of T7 bacteriophages using paper based sandwich ELISA

“…The conventional sandwich ELISA technique involves plate preparation using primary antibody. Researchers have demonstrated that antibodies can be physisorbed or ink jet printed on paper, and can be used for further applications [1][2][3]46]. In this study, the paper was used as an alternative surface to perform the sandwich ELISA test to detect viruses.…”

“…In the detection of health conditions through pathological diagnosis, the outsourcing of blood, urine and other biofluid samples to an analytical laboratory is a standard practice. Reliable instantaneous diagnoses without recourse to sophisticated laboratory and analytical instrumentation would be a significant innovation that promises to improve health outcomes in underprivileged and remote areas [1][2][3][4]. In addition, access to simple, dependable and low cost water and air filters that are able to capture and deactivate waterborne and airborne pathogens would be equally invaluable for preventing epidemic health threats through provision of safe water and air [4][5][6].…”

Laser micromachined hybrid open/paper microfluidic chips

“…[13][14][15][16] These hybrid chips can implement complex labon-a-chip techniques, which require many independently controlled flow rates, on a single monolithic chip without external instrumentation to drive fluid flow. In contrast to previous works that have demonstrated the elution of cells on paper substrates, 17,18 our hybrid chip enables cells to be controlled using conventional microfluidic structures such as single-cell capture sites, 19 inertial focusing, 20 and chaotic mixers. 21 In this paper, we demonstrate that integrated paper microchannels can be used to quantitatively control flow in conventional microchannels.…”

Red blood cell transport mechanisms in polyester thread-based blood typing devices

“…Previous paperbased tests required greater volumes of blood because of higher substrate absorbency, necessitating venepuncture [24]. Furthermore, operation of the thread-based test did not require the washing with saline or other reagents needed in paper tests [25,26], and therefore no handling of other liquids by users was necessary.…”