Using fluorescent quantum dots, an MIT research team has created a way to administer vaccinations and record a patient’s vaccination history in the skin. The researchers developed a microneedle platform that can selectively deliver microparticles into the skin in various patterns, which remain invisible to the naked eye but can be detected in the infrared (IR) using a smartphone that has the IR filter removed. The microparticles contain quantum dots, which store the person’s vaccination history in a pattern of dye that is delivered under the skin at the same time as the vaccine.
The copper-based quantum dots emit light in the near-infrared (NIR) spectrum and are about 4 nm in diameter. They are encapsulated in the biocompatible microparticles, which are about 20 μm in diameter. Encapsulation allows the dye to remain in place, under the skin, after being injected.