Gold Nanoparticles Cancer Treatment

It's no news that cancer is not an easy illness to treat. Many a times, the residual cancer cells can be found in the body even after the removal of tumours. At other times, a tumour can't be removed completely owing to the manner in which the cancer cells attach themselves to a vital organ. Hence, there was always the need for an effective method of detection and destruction of the cancer cells. Gold nanoparticles have provided great hope in this field and are being effectively used for destruction of cancer cells.

How gold nanoparticles cancer treatment works?

How the gold nanoparticles cancer treatment works is that a large number of gold nanoparticles are clustered inside a cancer cell and then the area is blasted using an infrared laser pulse. The laser pulse causes the fluid around the cluster to reach a temperature high enough for it to evaporate. This leads to destruction of the cancer cells, causing no harm to the healthy cells.

Please note that the nearby cells also remain unharmed by this process as the high temperature (because of the laser pulse) stays confined inside the nano-bubble surrounding the cluster.

There are various ways in which the gold nanoparticles can be clustered inside the cells, however, a method that's quite commonly used for this purpose is known as receptor-mediated endocytosis. In this method, the foreign objects (gold nanoparticles) attach themselves to the receptors on the outside areas of the cells (on their outer membranes).

How the particles are prepared for the gold nanoparticles cancer treatment?

The gold nanoparticles cancer treatment can only be effective if the nanoparticles are made to attach themselves to the cancer cells more easily than getting attached to the healthy cells. Else, the laser pulse may damage even the healthy tissues. To achieve this, the nanoparticles are delivered in the form of an antibody that attaches itself only to a particular type of cancer cell. Furthermore, the antibody attaches to the receptors located on the cell membranes.

It was found that the gold nanoparticles had to be of a particular optimum size in order to prevent their elimination from the cells. Any particles lesser than 10 nm in diameter can get quickly cleared out. And any that are greater than 100 nm in diameter face trouble getting internalized into the cells. The scientists discovered that the gold nanoparticles that worked best for such gold nanoparticles cancer treatment were around 60 nm in size.

These antibody coated gold nanoparticles can find their way into the cancer cells much more easily compared to the healthy cells. Please note that the average cluster size in case of cancer cells is normally around 300 nm, while it is around 64 nm in healthy cells.

As the tumours normally have leaky vascular systems, it works as a great natural advantage for this process. Hence, the gold particles spread rapidly and get incorporated through the entire cancerous region as soon as they are injected intravenously into the body area closer to the cancer. It was found that at least 24 hours' time (after the injection) is needed for the gold nanoparticles to form clusters inside the cells.

The blowup

The affected tissue is exposed to a near-infrared laser pulse for around 30 ps after the gold nanoparticles get clustered inside the cells. The laser light heats up the gold nanoparticles, leading to overeating of the cells. As a result, the fluid around the gold nanoparticles undergoes evaporation, causing it to expand and then collapse. In the end, it is the cancer cells that get destroyed and healthy cells remain untouched. And that's how the gold nanoparticles cancer treatment works overall.