“…Thus it is very important to develop an extremely high sensitivity, cost-effective and bio-based Hg 2+ sensor that can provide real-time determination of Hg 2+ levels in the environment, water, and food (Darbha, Ray, & Ray, 2007). A great effort has been exerted to detect Hg 2+ using various detection techniques, including optical spectroscopy (Jiang et al, 2012;Lim, Escobedo, Lowry, Xu, & Strongin, 2010;Rusin et al, 2003;Wang et al, 2005;Wang, Heon Lee, & Lu, 2008), electrochemical methods (Liu, Nie, Jiang, Shen, & Yu, 2009;Spãtaru, Sarada, Popa, Tryk, & Fujishima, 2001), high-performance liquid chromatography (Chen, Chen, Jin, & Wei, 2009;Lu, Zu, & Yam, 2007), inductively coupled plasma mass spectrometry, and so forth (Chen et al, 2009;Li et al, 2006). However, most of these techniques require expensive instrumentation and complicated sample preparation in certain cases, which make them inappropriate for point of use applications.…”