North Carolina State University researchers have devised a simple and large-scale method to arrange gold nanorods utilizing electrospun polymer dubbed ‘nano/microfibers.’
Arranging gold nanorods is critical, as their response to light varies with direction wherein the nanorods are pointed. Gold nanorods’ optical properties make them suitable for up-and-coming biomedical imaging technologies.
The researchers produced microscale and nanoscale fibers utilizing electrospinning method, in which the fibers are produced by solidifying a liquid polymer subsequent to their discharge from an electrospinning needle. They added the gold nanorods straightaway into the polymer solution by mixing them with the solution. The nanorods arrange during the formation of the fiber. The force encountered by the liquid polymer during its discharge from the needle forms ‘streamlines’ in the polymer solution.
Dr. Joe Tracy, a member of the research team, commented that this was the first time very short gold nanorods have been arranged in electrospun fibers. Particularly, the scientists utilized nanorods having an aspect ratio of 3.1. They used 49-nm long gold nanorods for the study. This aspect ratio is vital, as it manipulates the optical response of the nanorods and thus their optical properties.
Dr. Rich Spontak, one of the researchers, stated that the electrospinning method at the North Carolina State University is state-of-the-art and has produced numerous innovative and functional materials. The exciting feature of the method is the accomplishment of alignment at various length scales concurrently or multiscale alignment, he said. The fibers are arranged at huge length scales, while the nanorods are arranged at nanoscale, he added.