Laser incubator for blood cuts down testing time before a blood transfusion
The development could prevent fatal blood transfusions in critically ill patients, and can detect antibodies in pregnant women that can kill a fetus.
A team of Monash University researchers (Melbourne, Australia), together with industry partner Haemokinesis (Hallam, Australia), has developed a blood incubator using laser technology. The development could prevent fatal blood transfusions in critically ill patients, and can detect antibodies in pregnant women that can kill a fetus.
According to the team's paper that describes the work, these findings could bring pre-transfusion testing out of the pathology lab to the point-of-care, with blood incubation time totaling 40 seconds rather than the industry gold standard of five minutes.
The detection of immunoglobulin G (IgG) antibodies requires incubation at 37°C, often for up to 15 minutes. But current incubation technology relies on slow thermal procedures, such as heating blocks and hot-water baths. This delay adds to pathology costs and turnaround time, which substantially affects a patient's chance of survival.
To address this problem, the team at the Bioresource Processing Institute of Australia (BioPRIA), located within the Department of Chemical Engineering at Monash University, developed a laser incubation model in which a targeted illumination of a blood-antibody sample in a diagnostic gel card is converted into heat via photothermal absorption.
The laser-incubator heats the 75 μL blood-antibody sample to 37°C in under 30 seconds. Most importantly, no significant damage is detected to the cells or antibodies for laser incubations of up to 15 minutes.
"Laser incubation can be extremely valuable when time and accuracy is vital, especially in critical and emergency settings - like mass trauma - where pre-transfusion testing needs to be performed quickly in order to save lives," explains Dr. Clare Manderson of BioPRIA, who led the work. "We show that red blood cells act as photothermal agents under near-infrared laser incubation, triggering rapid antigen-antibody binding with no significant damage to the cells or antibodies for up to 15 minutes. This study demonstrates laser-incubated immunohematological testing to be both faster and more sensitive than current best practice, with clearly positive results seen from incubations of just 40 seconds."
For this study, the researchers explored the roles of incubation time and temperature of the IgG anti-D antibody and the Rh blood group system's D antigen, which indicates the positive or negative attributed to a person's ABO blood type group.
Anti-D is the most common antibody, and is present in a person's plasma. It is the biggest cause of hemolytic disease of the fetus and newborn - a blood disorder that occurs when the blood types of a mother and baby are incompatible. Accurate testing for pregnant women's antibodies is vital to save the life of the fetus.
Blood group type is based on the presence of antigens on the surface of the red blood cell membranes, consisting of proteins, glycoproteins, glycophorins, glycolipids, and polysaccharide macromolecules forming roughly 346 known blood groups.
"Giving blood transfusions to people isn't as simple as giving O-negative to anybody. The 'universal donor' of O-negative blood can seriously harm a lot of people, even kill them. The world of pre-transfusion of blood group typing is huge, and it's really important that it's done quickly and accurately to help save lives," Manderson says. "For the patient, it can mean that if there's a critical blood-loss scenario and they're in desperate need of a transfusion, they need to have their blood group typed and antibody-screened as quickly as possible. We're aiming to bring that down to seconds instead of tens of minutes."
While the technology isn't yet commercially available, Haemokinesis holds a patent for the innovation.
Full details of the work appear in the journal Scientific Reports.