Point-of-need determination of blood typing using a three-dimensional origami microfluidic paper based analytical device

We report a three-dimensional origami paper-based analytical device (3D-mu PAD) for ABO and Rh blood type detection using a three-dimensional origami microfluidic technology. A piece of rectangular shaped paper sizing (28.5 x 2) cm was folded into thirteen square layers of 2 cm edge. The first two layers formed the sample zone and distribution zones. Other layers were composed of 4 hydrophilic circle zones, which provide cylindrical channels when the paper layers are folded. Three circle zones on layers from 3 to 8 were pre-deposited with antibodies A, B and D and the reminder circle zone was considered as control. According to the design principle, when blood moves through channels of different antibodies it forms agglutination with those having its complementary blood group antigen. This lowers down the speed of blood movement through the channels. Therefore, the ability of blood movement through each channel was used as the basis of our detection (i.e., counting the number of layers through which blood moved for each channel, separately). The effects of the experimental parameters on the sensor's performance were investigated by using Placket-Burman and Central Composite Design methods. The device operation was validated by analyzing 67 blood samples. It was found that the if blood had complementary antigens, it moved 3-5 layers in the channels pre-deposited with anti-A or anti-B and 5-7 layer in channels pre-deposited with anti-D. Based on this observation, by single analysis we could determine the blood type of 95 % of samples compared to the gold standard method, which is currently used in blood transfusion labs. Replicate analysis resulted in 100 % accuracy. The device was stable for 14 days before using. However, after using, it was stable for at least 1 year.