Researchers at Florida Atlantic University have developed a microfluidic chip that can rapidly assess blood samples from sickle cell disease patients to help monitor the disease. The technique is much faster and more convenient than traditional optical microscopy assessments.
Sickle cell disease affects approximately 100,000 individuals in the U.S. and millions of people throughout the world. Red blood cells in those affected become misshapen (forming a “sickle” shape) and sticky, and can block blood flow and break down. This can lead to a variety of serious symptoms, such as organ failure, stroke, and severe pain, both chronic and acute. The pain episodes are often unpredictable, making it difficult to pre-empt and avoid them.
Managing sickle cell disease requires that clinicians are aware of the ongoing sickling behavior in patient red blood cells. Ideally, such changes would be detected before cell damage and serious symptoms develop, but current optical microscopy techniques to monitor the disease are time consuming and can’t provide clinicians with regular, real-time updates on cell behavior.
This issue inspired the Florida Atlantic University researchers to develop a more convenient method to monitor sickle cell disease. Their solution consists of a microfluidic chip that uses impedance measurements to assess red blood cell behavior. The chip is loaded with a patient blood sample and the sample is exposed to conditions of high and low oxygen, which can stimulate the cells to sickle and unsickle. Electrical impedance detection then measures the rate of sickling and unsickling. This can tell clinicians about the potential of the cells to contribute to blood vessel blockage and abnormal blood flow.
The researchers have been able to correlate the measurements they made using the new microfluidic device with important patient hematological parameters, and the technique could provide clinicians with information on disease severity, the risk of blood vessel blockage, and whether a specific treatment is working or not.
“The combination of electrical impedance measurement and on-chip hypoxia control provides a promising method for rapid assessment of the dynamic processes of cell sickling and unsickling in patients with sickle cell disease,” said Sarah E. Du, a researcher involved in the study. “In addition, electrical impedance measurement is naturally quantitative, real-time, and offers a convenience in direct or indirect contact with the samples of interest, allowing integrations to microfluidics platform and optical microscopy.”
See a video about the technique below:
Study in ACS Sensors: Electrical Impedance Characterization of Erythrocyte Response to Cyclic Hypoxia in Sickle Cell Disease
Flashback: A SMART Idea: Point-of-Care Diagnostic for Sickle Cell Disease and Malaria (Interview)