doi:10.1038/nindia.2015.128 Published online 19 September 2015
Researchers have synthesized a sensitive biosensor that can detect minute traces of bisphenol A (BPA), a polymer widely used in the manufacture of drinking water bottles, baby bottles and food packaging1. This biosensor will be useful for detecting BPA in biological and environmental samples.
Being structurally similar to natural estrogen, BPA disrupts the hormone secretion process, and can cause cardiovascular and liver diseases. Existing methods for detecting BPA are expensive and tedious.
To develop a fast and efficient BPA-sensing method, the researchers fabricated the biosensor from a nanocomposite consisting of a few layers of enzyme-modified reduced graphene oxide and chitosan. They then evaluated the biosensor’s efficiency to detect different concentrations of BPA in solutions. They found that the peak current gradually increased with increasing BPA concentration, which they attributed to an enzyme on the biosensor that chemically converts BPA into an organic compound. This reaction generates electrons that are transferred from solution to the nanocomposite, resulting in increased current.
The biosensor showed a fast response time of 10 seconds over a wide range of BPA concentrations. It also selectively detected BPA in the presence of other organic compounds and was stable for 7 weeks, losing only 10% of its original sensitivity.
The biosensor could potentially be used to detect BPA in plastic bottles, the researchers say.