Credit: National Cancer Institute
Key points:
- A new material made from ultra-tiny silicon nanoparticles has many applications, including solar cells and better cancer treatment.
- The new material increases the speed with which two molecules exchange energy.
- Applications include bioimaging, light-based 3D printing, and light sensors that would help self-driving cars through foggy weather.
A new material, created at the little-explored intersection of organic and inorganic chemistry, could usher in the next generation of cancer treatments.
The composite is made of ultra-tiny silicon nanoparticles, and an organic element closely related to those used in OLED televisions. It is capable of increasing the speed with which two molecules can exchange energy, and of converting lower-energy light into higher-energy light.
High-energy light, such as ultraviolet laser light, can form free radicals able to attack cancer tissue. UV light, however, doesn’t travel far enough into tissues to generate therapeutic radicals close to the tumor site. On the other hand, near-infrared light penetrates deeply into the body, but doesn’t have enough energy to generate the radicals.
With the new material, the research team demonstrated it is possible to achieve the emission of light with higher energy than the one aimed at the material, known as photon up-conversion. In addition to being efficient, the silicon “dots” that form the base of this high-energy material are not toxic.
There are a variety of applications involving infrared light that could be improved with the new silicon dot-based material, including bioimaging, light-based 3D printing, and light sensors that would help self-driving cars through foggy weather. Not only is the research team excited about the potential applications, but about being able to design a new class of composite materials.
“We now know how to take two extremely different substances and bond them strongly enough to create not just a mixture, but an entirely new material with distinct properties,” said Sean Roberts, University of Texas at Austin chemistry professor and corresponding paper author. “This is one of the first times this has been achieved.”