Rapid and inexpensive blood typing on thermoplastic chips
Journal
Lab Chip
Journal Volume
15
Journal Issue
24
Pages
4533--4541
Date Issued
2015
Author(s)
Abstract
A portable and cost-effective colorimetric diagnostic device was fabricated for rapid ABO and Rh blood typing. Using microfluidic construction on a thermoplastic chip, blood antibodies were preloaded into a reaction channel and exposed to blood samples to initiate a haemagglutination reaction. Downstream high-aspect ratio filters, composed of 2 μm high microslits, block agglutinated red blood cells (RBCs) to turn the reaction channel red, indicating the presence of the corresponding blood antigen. Users manually actuate the blood sample using a simple screw pump that drives the solution through serpentine reaction channels and chaotic micromixers for maximum interaction of the preloaded antibodies with the blood sample antigens. Mismatched RBCs and antibodies elute from the channel into an outlet reservoir based on the rheological properties of RBCs with no colorimetric change. As a result, unambiguous blood typing tests can be distinguished by the naked eye in as little as 1 min. Blood disorders, such as thalassemia, can also be distinguished using the device. The required blood volume for the test is just 1 μL, which can be obtained by the less invasive finger pricking method. The low reagent consumption, manual driving force, low-cost of parts, high yield, and robust fabrication process make this device sensitive, accurate, and simple enough to use without specialized training in resource constrained settings.
Type
journal article