What if I told you … that shining a laser on a blood sample could tell you whether or not your symptoms were due to a virus or a bacteria? What if this handheld biosensor could detect virus antibodies too? The simple fact that there is no need to send the test off and wait for results, much less add further cost to the overall process is a real bonus for the patient and the system. It is even possible that you could skip the doctor’s office and just go to the pharmacy because the blood test is really that good.
The image above is just one example of the technology in play here: laser interferometry. While the image of LIGO given above is for detecting gravitational waves (gimme a break, I’m a Physics Professor), shining two light beams on the blood sample is the same thing. Basically, laser interferometry creates what Physicists call an interference pattern. The nature of that pattern is indicative of what it interfered with. For example, proteins like procalcitonin, which increases in blood when a patient has a bacterial infection.
For more information on the super science nerdy research, click the link.
Isabel Barth et al. Common-path interferometric label-free protein sensing with resonant dielectric nanostructures, Light: Science & Applications (2020). DOI: 10.1038/s41377-020-0336-6