Nanogold refers to tiny gold particles with a diameter of 1 to 100nm. It has high electron density, dielectric properties and catalysis, and can be combined with a variety of biological macromolecules without affecting its biological activity. Gold nanoparticles with different particle sizes can be easily prepared from chloroauric acid by reduction method, and their colors range from red to purple according to different diameters.

Effects on human skin:

1. Nanogold particles activate fibrous cells, which can awaken sleeping cells, strengthen the tightness between collagen and fibers, repair scars, smooth wrinkles, tighten skin, improve cell activity, resist oxidation and aging, and make skin spontaneously contract rhythmically.

2. By massaging the nano-gold particles, they can fully penetrate into the dermal layer of the skin, double the water-holding capacity of the skin, and produce more collagen to fight free radicals, thus preventing skin aging, reducing facial fine lines, making the skin full, firm and elastic, and activating the whole skin from cells.

3. Nano-gold spheres have catalytic activity, which can quickly and thoroughly penetrate into dermal reticular layer, form elastic omentum, closely connect, repair fragile damaged cells, activate fibroblasts, improve skin elasticity and tension, closely combine elastic fibers and collagen fibers, smooth wrinkles, tighten skin, achieve antioxidant and antibacterial effects, alleviate various skin problems, and deeply regulate problems caused by sebum lesions.

Extended data

Researchers in China have made great progress in the study of nano-gold catalysis.

Supported by the National Natural Science Foundation of China (project numbers: 2 1590792, 9 1645203, 2 152 109 1), the Li Juan Research Group of Tsinghua University Department of Chemistry and Wang Chongmin Research Group of Northwest Pacific National Laboratory and Pittsburgh, USA.

The research results were published in PNAS (Proceedings of the National Academy of America) on July 9, 20 18, and the topic was the size effect and dynamic structural changes of carbon monoxide oxidation catalyzed by gold nanoparticles.

Since the discovery of nano-sized (2 ~ 5 nm) gold particles with low-temperature catalytic activity in the late 1980s, nano-gold catalysis has become one of the milestones in the field of heterogeneous catalysis. For more than 30 years, nano-sized supported gold catalysts have been widely studied in experiment and theory, but its remarkable "size effect" is still a mystery.