Research Highlight

Cadmium detectives

doi:10.1038/nindia.2009.30 Published online 11 February 2009

Researchers have made a polymeric membrane electrode to detect cadmium (Cd) in cigarette samples1. The electrode detects Cd very fast and with an easy-to-use device.

A by-product of metal plating, cadmium-nickel batteries, mining, pigments, and phosphate fertilizers, Cd poses health hazard for humans. As an alternative to expensive detection methods, the researchers made PVC (poly vinyl chloride-based membranes dissolving appropriate amounts of Schiff bases, anionic additives and plasticizers (mostly phthalates) containing ionophore (a lipid soluble substance that allows ion movement across the membrane).

The membranes were exposed to Cd ions in varying concentration of cadmium nitrate solution and other positively charged ions. The membrane electrodes were significantly selective to Cd ion over the other ions. The response time of the electrodes was 11 seconds.

Tobacco leaves naturally accumulate high levels of Cd and are an important source of air Cd exposure for smokers. To study the efficacy of the membrane electrode in the detection of Cd in tobacco leaves, the researchers exposed five kinds of tobacco from different cigarette samples to the electrodes. "Membrane electrode can be successfully used in determination of cadmium concentration in tobacco leaves used by the cigarette manufacturing companies," says lead researcher Vinod C. Gupta.

The authors of this work are from: Department of Chemistry, Indian Institute of Technology Roorkee, India and department of Chemistry, College of Sciences, University of Sharjah, United Arab Emirates


  1. Gupta, K. V. et al. Nano level detection of Cd (II) using poly (vinyl chloride) based membranes of Schiff bases. Anal. Chim. Acta. 634, 36-43 (2009)