Research Highlight

Sunlight shapes cancer drug carrier

doi:10.1038/nindia.2012.108 Published online 27 July 2012

New research has shown that nutrient agar irradiated with sunlight could be a biocompatible coating for gold nanoparticles. Such nanoparticles could be used to deliver mercaptopurine, a drug used to treat laryngeal cancer, thus providing an eco-friendly way to make a cancer-drug carrier.

Gold nanoparticles are increasingly synthesised using plant extracts owing to their potential for biomedical and optoelectronic applications. Researchers often use biopolymer coatings to yield biocompatible gold nanoparticles, but traditional techniques are time-consuming and expensive.

To develop a simple process, the researchers exposed a mixture of gold chloride and nutrient agar solution to sunlight and made nutrient-agar-coated gold nanoparticles. They attached mercaptopurine to the nanoparticles and carried out drug-release studies in phosphate-buffered saline.

The researchers observed an initial burst of mercaptopurine release during the first hour, followed by sustained and prolonged release of 25.33% over the next four hours. They explored the drug-carrying and imaging potentials of these nanoparticles in zebra fish embryo and larvae models by attaching a fluorescent dye to the nanoparticles.

This fluorescence was detected in the embryo and in the head and stomach regions of larvae. Also, nanoparticles attached with mercaptopurine and folic acid showed significantly more cytotoxic effects than free mercaptopurine or mercaptopurine-attached nanoparticles after 24 hours.

The authors of this work are from: Department of Biochemistry, Central Leather Research Institute, Council of Scientific and Industrial Research, Bioproducts Laboratory, Central Leather Research Institute, and Central Institute of Brackish Water Aquaculture, Chennai, Department of Pharmaceutics, Anna University, Trichy, Thanthai Hansroever College, Perambalur, Tamilnadu, India.


  1. Ganeshkumar, M. et al. Sun light mediated synthesis of gold nanoparticles as carrier for 6-mercaptopurine: Preparation, characterization and toxicity studies in zebrafish embryo model. J. Mater. Res. Bull. doi: 10.1016/j.materresbull.2012.06.015 (2012)