Portable device makes rapid count of white blood cells

A device that quickly counts a person’s white blood cells with a single drop of blood has been designed and tested by a spinoff company from Rutgers University in New Jersey.


The CytoTracker Leukometer device is designed to aid the detection of elevated or reduced white blood cell counts, which is a critical signal of a patient’s immune system status. A high or low white blood cell count may indicate the intensity of an infection, the presence of life-threatening conditions or determine how patients are responding to chemotherapy and psychotropic drugs.

The development of the device by researchers at Rutgers startup RizLab Health Inc. along with the clinical validation is described in PLOS One.  

Mehdi Javanmard, a professor in the Department of Electrical and Computer Engineering at the Rutgers School of Engineering, is the co-founder and CEO of Princeton-based RizLab Health Inc.

“Normally, doing a blood count requires a phlebotomist taking a needle stick and collecting significant amounts of venous blood and sending the samples off to labs where they are tested, sometimes taking hours or even days,” Javanmard said in a statement. “Our handheld device enables near-patient testing, while only requiring a tiny amount of blood and returning results within minutes, allowing clinicians to make decisions almost immediately.”

The device was tested in trials by pitting the device in a head-to-head comparison with a lab benchtop haematology analyser, which is a conventional blood testing technique. The results showed the CytoTracker Leukometer to be at least 97 per cent accurate and met clinical standards.

The CytoTracker Leukometer, indicating a level of white blood cells that falls within the "healthy" range. The portable device quickly delivers readings based on a single drop of blood - RizLab Health Inc.

White blood cells, or leukocytes, protect the body from infection. Colourless, they constitute about one per cent of human blood and are formed mostly in bone marrow. Certain subtypes of leukocytes have different functions, such as neutrophils that kill bacteria, fungi and foreign debris.

A low white blood cell count indicates that a person is prone to infection. A high white blood cell count means either an infection exists or there is an underlying medical condition.

Javanmard envisions multiple uses for the device. Sepsis in a patient entering an emergency room could more quickly be detected on the device than through present methods requiring a blood draw and a lab test, he said. Medical oncologists could rapidly determine whether patients undergoing chemotherapy need a white blood cell stimulant.

Javanmard and his students have sought to perfect the capabilities of a miniaturised electronic cytometric technique that detects microscopic particles by directing them through minute channels containing electrodes. In one recent advance, Javanmard said he and lab members used the cell-flow technique to develop a test so sensitive it could someday transform medical approaches to epidemics.

RizLab Health has focused on further advanced development and manufacturing of electronic cytometry with the goal of obtaining regulatory approval and commercialisation.