A Comparative Study for Detection of Melamine in Solution by Interference Sensing Using Functionalized Silver Nanoparticles

Abstract

In this research an attempt has been made for instantaneous sensing of melamine, a potential milk adulterant, at room temperature with the help of bio-functionalized silver nanoparticles. The bio-functionalized nanoparticles were made using leaf extracts of Parthenium hysterophorous and Calotropis procera. Also these methods were compared with the nanoparticles that were functionalized with sulfanillic acid. Colorimetric change was the basis of sensing the melamine using these bio-functionalized silver nanoparticles. Melamine upto a limit of 0.1 ppm was detected by the particles prepared using Parthenium hysterophorous leaf extract at room temperature. UV-visible spectroscopy (200–800 nm range) was used to detect the changes in the absorbance of silver nanoparticles with the addition of melamine in different concentrations. DLS studies were carried out to confirm the presence of nanoparticles and to study their surface morphology during sensing. Comparative study showed that Parthenium hysterophorous (noxious hysterophorous) leaf extract was far better and accurate in detecting melamine and was as accurate as the silver nanoparticles functionalized with sulfanillic acid. This can be attributed to the fact that Parthenium hysterophorous leaf extract contains caffeic acid which worked as a reducing agent and also as the bio functionalized chemical. Thus, this method can be further used as a rapid detection of melamine. In addition, this method can be converted into prototype for detection of melamine in industries.