Posted: April 20, 2007

Gold nanoparticles to be used in early diagnostics and treatment of cancer

(Nanowerk News) By attaching gold nanoparticles to cancer cells, earlier detection will be possible. Using photoacoustics – a combination of laser light and ultrasound-, scientists of the BMTI Institute for Biomedical Technology at the University of Twente in The Netherlands expect to improve diagnostics, especially in the early stage of the disease. A step further is the use of the gold particles in actual treatment of cancer. For new in vitro and preclinical tests, the scientists have received funding from the Dutch research programme IOP Photonic Devices.
Gold nanoparticles have highly interesting properties: they can be heated rapidly whenever infrared light of the right wavelength touches them. By attaching antibodies to the nanorods, which can recognize a specific cancer cell, this heating phenomenon can be used in cancer detection. Heating of the gold results in a varying pressure near the particle. This pressure change, in turn is expressed in the generation of ultrasound. In this way, light from a laser eventually results in sound. This acoustic signal gives valuable information about the presence of cancer cells.
The scientists led by prof. Ton van Leeuwen of the Biophysical Engineering Group expect better results than currently possible with imaging techniques. X-Ray and MRI, for example, both have insufficient contrast to discern cancer cells from healthy tissue in the very beginning of the disease.
Photothermal therapy
The phenomenon resulting in rapid heating of the gold particles, is called plasmon resonance: the shape of the particles determines the wavelength at which this happens. The temperature rise can be up to 100 degrees. For the scientists this is an indication for possible use in cancer treatment. Photothermal therapy would use the heated gold to destroy the tumor. Another option would be to include gold particles in capsules filled with cancer medication: the capsule attaches to the cancer cell, is heated and the medicine is released locally.
Both diagnostic and therapeutic applications will be investigated by the UT scientists together with colleagues from the Erasmus MC in Rotterdam and two companies: Esoate Europe and Luminostix. The project is financed from the innovation oriented programme IOP Photonic Devices of the Dutch Ministry of Economic Affairs. Dr. Srirang Manohar from the Biophysical Engineering group already received a VENI grant for his initial research on the applications of gold nanoparticles, and there’s also been related research within the Non Invasive Molecular Tumor Imaging and Killing (NIMTIK) focus project of the BMTI Institute.
Source: University of Twente