A microfluidic biochip for blood cell counts at the point-of-care

A microfluidic biochip for blood cell counts at the point-of-care

Teams of researchers from the University of Illinois at Urbana-Champaign (UIUC) have demonstrated a biosensor capable of counting the blood cells electrically using only a drop of blood.

The blood cell count is among the most ubiquitous diagnostic tests in primary health care. The gold standard routinely used in hospitals and testing laboratories is a hematology analyzer, which is large and expensive equipment, and requires trained technicians and physical sample transportation.It slows turn-around time, limits throughput in hospitals, and limits accessibility in resource-limited settings.

Researchers developed a biosensor to count red blood cell, platelet, and white blood cell counts, and its 3-part differential at the point-of-care while using only 11 microL of blood.

The microfluidic device can electrically count the different types of blood cells based on their size and membrane properties. To count leukocyte and its differentials, red blood cells are selectively lysed and the remaining white blood cells were individually counted. The specific cells like neutrophils were counted using multi-frequency analysis, which probe the membrane properties of the cells.

However, for red blood cells and platelets, 1 microL of whole blood is diluted with PBS on-chip and the cells are counted electrically. The total time for measurement is under 20 minutes. The report appears in the journal TECHNOLOGY.

The team from UIUC is working now to further develop a first portable prototype of the cell counter. "The cartridges will be disposable and the size of a credit card. The base unit or the reader will be portable and possibly hand-held. Our technology has the potential to reduce the cost of the test to less than $10 as compared to $100 or more currently charged," says the author.