English Ivy Nanoparticles Found to Protect Skin from UV Radiation

Posted: June 30, 2010

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Biodegradation of the nanoparticles was determined through a number of digestion techniques. The researchers incubated the ivy nanoparticles in RPMI at 37°C for up to 24 hr and found the nanoparticles were not digested as assessed by AFM. To test the ability of the particles to be broken down by enzymatic digestion, proteinase K was used. After incubation for 30 min, the nanoparticles were no longer detectable by AFM. Therefore, after enzymatic digestion, the ivy nanoparticles were degraded and lost their normal structure.

Finally, a mathematical model was developed to determine the potential for ivy nanoparticles to penetrate through human skin. Based on the model and obtained parameters, the dynamics of nanoparticle diffusion into the SC layer of the skin were simulated. While nanoparticles with a diameter of less than 10 nm had a chance to reach deeper into the SC layers, nanoparticles over 40 nm could only reach 5–8 μm into the SC layer after 8 hr of application, and 8–13 μm after 20 hr. The researchers therefore determined that with the standard 8 hr of sun exposure, the ivy nanoparticles, at 65 nm, could not penetrate the stratum corneum.

In addition to demonstrating that the ivy nanoparticles can be used as a UV filter in sunscreens, the researchers also emphasized that these nanoparticles demonstrated an adhesive effect, which reportedly enhances the UV protective ability of the nanoparticles.

Since question and debate remains over the safety of metallic nanoparticles in sunscreens, interesting alternatives such as these pose new opportunities for formulators in this highly debated field.