Gold nanoparticles generally tend to clump thereby avoiding its use as an anti-cancer therapy. Thus, the researchers from Hokkaido University have found a technique to prevent gold nanoparticles from clumping. The researchers found the attaching of ring-shaped synthetic compounds to the gold nanoparticles to assist it from preserving the essential light-absorbing properties. The study published in the journal Nature Communications I explains the importance of the unique light-absorbing properties that helps the metal nanoparticles to be broadly used in biomedical, optical, and electronic field.

Generally, the gold nanoparticles when introduced into tumors use light to kill the cancerous cells but in the process they tend to clump together such that the light absorption capability is lost in the long run. The clumping is found to happen due to factors such as acidity, temperature, and salt concentration. The researchers have been trying to have the particles dispersed in the targeted area and they had found polyethylene glycol (PEG) coating to help achieved success. PEG is found to inhibit the clumping of the gold nanoparticles in both the lab and living organisms. However, there is still more study and improvement required. The latest discovery dealt with mixing of gold nanoparticles with ring-shaped PEG instead of the linear PEG to attain high dispersion.

The 'cyclic-PEG' (c-PEG) is designed to attach to the surfaces of the nanoparticles without developing any chemical bonds and this process is known as physisorption. Further, these nanoparticles even in the heated, dried, and frozen condition remained dispersed. The c-PEG-coated gold nanoparticles exhibited the ability to clear from the blood for better accumulation in the tumors than the liner PEG-coated gold nanoparticles. The researchers are still looking for even better accumulation and are thus working toward fine-tuning the nanoparticles to enhance its application in the medicinal sector.