Blood coagulation analysis is useful for determining proper medication for medical conditions such as hemophilia, liver disease, and cardiac surgeries and has many uses in laboratories, hospitals, and even at home. Many diseases affect the in vivo coagulation of blood, including Hemophilia A and B, thrombocythmia, Christmas disease, and prothrombin deficiency. Treatment requires medication with either coagulants or anticoagulants such as heparin or tannin. Near-patient blood testing during cardiac surgery is important because blood clotting must be monitored to ensure a successful operation. Additionally, in order to ensure proper medication, at-home testing would be a great benefit for individuals suffering from these diseases. Clearly there is a need for low-cost blood coagulation analyzers, preferably, disposable, single-use devices so as to avoid autoclaving and other cleaning procedures.
Researchers at the University of Michigan Department of Electrical Engineering have developed a new microsystem capable of detecting the clotting time of blood. Using a microfluidic channel and an appropriate sensor, changes in blood flow can be measured, and thus, the time in which blood clots can be determined. This system takes a small amount of blood by means of capillary action and pressure differentials, then dispenses it through the innovative microfluidic channel. As clotting occurs, the sensor in the device will detect the reduction in flow and a time is recorded. The sensor can be, but is not limited to, an impedance sensor, a capacitance sensor, or a digital switch readout.
Applications and Advantages
- Microsystem for determining blood clotting time
- Low-cost, single-use device
- No moving parts or expensive optical sensors or magnets