Researchers in the United States have developed a low-cost printer that helps HIV patients living in low-resource settings to track the health of their cells.
Patients with HIV are encouraged to participate in regular checkups to keep track of their health. In high resource settings, devices known as flow cytometers complete the tests by analyzing the blood. Flow cytometers, however, are bulky machines that run on electricity. The machines also cost upwards of US$50,000.
The new less expensive device is ideal for the developing countries, where the battery-operated, portable machine can help clinicians count the number of CD4 cells — cells that are attacked by HIV — in the body.
After drawing a patient's blood, clinicians mix in magnetic micro-scale beads that latch on to CD4 cells in the blood. The mixture is then placed in an inkjet printer that has been modified to print out cells instead of ink. Rather than printing vertically onto a sheet of paper, the cells are shot out horizontally onto a magnetized microscopic slide.
CD4 cells in the blood automatically attach to the slide, while other cells that do not need to be counted dribble down into an excess container. Doctors can then look at the slide through a microscope to count the number of CD4 cells on it. That number is inserted into an equation that calculates the total number of CD4 cells in the individual's body. The procedure takes as little as 20 minutes, resulting in ultra-quick results.