To make red blood cells in the lab, study leader Samir Mitragotri and colleagues started with spheres of biodegradable polymer. They then exposed the spheres to isopropanol, which collapsed them into the discoid shape characteristic of red blood cells. The researchers then layered proteins — either albumin or hemoglobin — onto the doughnut-shaped disks, cross-linked the proteins to give them extra strength and stability, and finally dissolved away the PLGA template to leave only a strong but flexible shell [The Scientist].
Mitragotri’s creations are about 7 microns across—the same diameter as real red bloods cells—and they have the same disc-like shape as their real-world counterparts. They act like real cells, too, he says. “The soft protein shell makes them squishy and elastic,” says Mitragotri. “They can squeeze through capillaries smaller than their own diameter, just like real blood cells” [New Scientist]. And perhaps most impressively, they can carry substances like the real thing does. Mitragotri’s team of researchers experimented with hemoglobin and the anti-blood clotting drug heparin; the synthetic cells could soak up either one and release it later.
Link via io9 | Image: Nishit Doshi