The Great Applications Of Gold Nanorods In The Biological Field

As gold is a noble metal that does not get oxidized or corroded easily by any other chemical element, it has larger electromagnetic field and stronger radiative qualities, like absorption and scattering of light.

Moreover, these gold nanorods have stronger plasmonic fields than other nanoparticles, mainly due to their shapes, showing greater tunability and compatibility with all biological objects. The optical properties of these nanorods allow tuning of the shape or size of these particles, so that their power of absorption or scattering light can be changed within the visible range of colors, up to the infrared zone of their electromagnetic spectrum.

Hence, this light scattering property of the nanorods of gold has made them perfectly compatible for using in the biomedical diagnosis process of many diseases, like cancer, including the sensing and imaging of the cancerous cells.

The nonradioactive photo thermal property has also made these nanorods well-suited for photo thermal therapy, as well as for the gene delivery, which are used for the treatment of cancer, by using the electromagnetic radiation of these nanoparticles.

Detailed study of the properties of gold nanorods used in biomedical diagnosis

While the cell membranes and some cell structures, like mitochondria and nucleus scatter light to different ranges; some ingredients residing within the cells, like hemoglobin or oxy-hemoglobin, melanin and water absorb the light instantly. The function of the golden nanorods is to map these absorption or scattering of light by these cell structures, to identify the affected tissues, using the optical imaging techniques, thus imaging the true status of those cancerous cells.

Though all nanoparticles have the ability of performing this imaging function, the nanorods are particularly more effective in this respect, due to their specific cylindrical structure and the ability to bear more longitudinal surface Plasmon. Moreover, the ability of stronger functionalization of these nanorods with the antibodies or any other biomolecule of the body helps these nanoparticles to get attached more easily to the body cells, which they need to image optically.

Unlike any other nanoparticle or marker molecule, used for optical imaging, the nanorods never decompose or become photo bleached, when placed under any fluorescence microscope, due to their high resistance power. Therefore, these nanorods are also used in Biosensing applications, which are alternatively used for diagnosis of cancer.

In the photo thermal therapy of cancer, heat is applied to destroy the infected cells or cancerous tumor. The golden nanorods are now proved to be the best carrier of this heat to the specific targeted cells, without causing any harm to other body cells. This application is possible due to the high wavelength of the Plasmon resonance mode of these nanorods and their better power of converting light into thermal energy.

I am Chetan & an oncologist, researching on cancer treatments, I have found these gold nanorods highly beneficial imaging of the cancerous cells.