Thread as a substrate for low-cost point-of-care diagnostics

This study presents new applications of thread-based microfluidic systems in chemical and biochemical diagnostics. Our recent reports have demonstrated the capability of fabricating low-cost microfluidic devices using ubiquitous multifilament materials such as threads. The gaps between fibres in threads provide capillary wicking channels for liquid transport; therefore, liquid can penetrate along threads without the need of external forces. The new threadbased system, combined with the cheap dosing tools, is capable of easily and rapidly semi-quantifying the concentration of analytes in human body fluids. The utility of this system is further extended for the rapid and easy blood grouping with only small amount of whole blood (~ 2 μL for ABO blood typing), which is an essential test before blood transfusion. These low-cost and portable microfluidic devices are easy to fabricate, simple to use, and do not require powers such as electricity; thus providing a desirable analytical platform for point-of-care applications.