Vitamin-sensing, antibacterial nanoparticles
doi:10.1038/nindia.2016.27 Published online 24 February 2016
Researchers have synthesized cerium-doped nickel oxide nanoparticles that can detect minute traces of riboflavin, a member of the vitamin B family, in urine as well as inhibit the growth of several pathogenic bacteria1. These nanoparticles could potentially be used to develop biosensors and treat bacterial infections.
Riboflavin is essential for body growth and the production of red blood cells. A deficiency of riboflavin leads to slow growth, eye fatigue and digestive problems.
To develop a simple method for detecting riboflavin, the researchers produced cerium-doped nickel oxide nanoparticles, deposited them on glassy carbon electrodes and probed their ability to detect riboflavin. The peak current of the nanoparticle-coated electrodes was found to increase with increasing riboflavin concentration.
The modified electrodes could detect extremely low concentrations of riboflavin and could selectively detect riboflavin in the presence of interfering agents such as serotonin, epinephrine, cystamine, dopamine and tyrosine, which are usually found in body fluids.
The nanoparticles showed significant antibacterial activities against bacteria such as Klebsiella pneumoniae, Salmonella typhi, Bacillus cereus, Bacillus subtilis and Staphylococcus aureus. The positively charged nanoparticles easily bound to negatively charged bacterial cells through electrostatic interactions and generated reactive oxygen species that eventually killed the bacteria.
After 100 sequential scans, the nanoparticle-coated electrodes retained 86% of their original efficiency to detect riboflavin, suggesting that they can function as biosensors, the researchers say.
1. Muthukumaran, P. et al. Cerium doped nickel-oxide nanostructures for riboflavin biosensing and antibacterial applications. New J. Chem. (2016) doi: 10.1039/C5NJ03539B