Little upset with gray hairs? Or maybe you’re one of those young people with persisting gray spots. If you like to live on the cutting edge, French scientists may have something for you.
Shrutisagar et al. from Institut de Chimie Moléculaire et des Matériaux d’Orsay recently published findings in Nano Letters that might offer a radical hair dye solution. They submerged white hairs into some fluorescent gold nanoparticles in solution. Hairs spontaneously turned yellow within a day. After 15 more, hairs develop a dark brown hue. Researchers note the color persists despite repeated washes.
The synthesis and detailed characterization of gold nanoparticles (AuNPs) inside human hair has been achieved by treatment of hair with HAuCl4 in alkaline medium. The AuNPs, which show a strong red fluorescence under blue light, are generated inside the fiber and are arranged in the cortex in a remarkably regular pattern of whorls based on concentric circles, like a fingerprint. It opens an area of genuine nanocomposites with novel properties due to AuNPs inside the hair shaft. (Credit: American Chemical Society)
The result: deep, dark brown hair dye that doesn’t wash out. The hair fibers also fluoresce red under blue light!
Granted, not everyone can afford to synthesize gold nanoparticles and treat their hair. Gold’s pretty expensive as it is (and has been increasing over the past 10 years!).