London, March 19 (IANS): An Indian-origin scientist in Germany has discovered a new, unexpected role for green tea - to improve the image quality of magnetic resonance imaging (MRIs) testing.

Sanjay Mathur, director of the institute of inorganic chemistry at University of Cologne, Cologne, Germany, successfully used compounds from green tea to help image cancer tumours in mice.

Using a simple, one-step process, Mathur and his team coated iron-oxide nanoparticles with green-tea compounds called catechins and administered them to mice with cancer.

MRIs demonstrated that the novel imaging agents gathered in tumour cells and showed a strong contrast from surrounding non-tumour cells.

"The catechin-coated nanoparticles are promising candidates for use in MRIs and related applications," Mathur said in his paper that appeared in journal ACS Applied Materials & Interfaces.

Recent research has revealed the potential usefulness of nanoparticles - iron oxide in particular - to make biomedical imaging better. But the nanoparticles have their disadvantages.

They tend to cluster together easily and need help getting to their destinations in the body. To address these issues, researchers have recently tried attaching natural nutrients to the nanoparticles.

Mathur's team wanted to see if compounds from green tea, which research suggests has anticancer and anti-inflammatory properties, could play this role.

An MRI is a test that uses a magnetic field and pulses of radio wave energy to create pictures of organs and structures inside the body.