A new way to detect anaemia that relies on optical light absorbance to measure haemoglobin levels using whole blood in a microfluidic device is claimed by researchers to be a vast improvement over existing tests that require hemolysis (rupturing) of blood samples and lab facilities.
“The most exciting aspect to this analyser is that it uses whole blood (blood components intact) and doesn’t require additional steps and reagents to prepare a sample,” says Nathan Sniadecki, professor of mechanical engineering at the University of Washington, Seattle, and an author of the report on the novel approach.
Anaemia, a disease caused by low concentration of haemoglobin in red blood cells, results primarily from a lack of iron in the diet but can co-occur with other conditions, such as malaria or genetic disorders. The World Health Organisation (WHO) considers it as a global health problem affecting over a quarter of the global population, a vast number of which are women and children in resource-poor countries.
Nikita Taparia, a doctoral candidate at Sniadecki’s laboratory, says the microfluid channel technique they developed is ideal for use in the field. “All that is needed are a few drops of blood to be put into the microfluid channel.” Microfluidics deals with the behaviour and control of fluids in a constrained, typically sub-millimetre space.
“The analyser takes advantage of the optical properties of blood, such as absorption and scattering of light, to measure haemoglobin concentration. Anaemic blood transmits more light compared to normal blood, so the severity of anaemia can be measured as a ratio of transmitted to original light intensity,” emphasises Taparia.
Jose Lopez, professor at the University of Washington’s school of medicine and a member of the Bloodworks Research Institute NW in Seattle, says the new approach “can be useful to diagnose infectious disorders associated with anaemia (such as malaria) and to screen for genetic anaemias such as thalassemia and sickle cell disease.”
J.P. Peña-Rosas, who coordinates the Evidence and Programme Guidance, department of nutrition for health and development at WHO, Geneva, says that the global body will convene a technical consultation to discuss the interpretation of haemoglobin concentrations for assessing anaemia status in individuals and populations.
