Table 1.

Comparison between the detection limit of our sensor and that of other jobs.

Authors	L.O.D [M]	Type of sensor
Our Work	10–6	Optical
Moozarm Nia et al., 2015 [52]	5·10−5	Optical
Shu et al., 2007 [53]	10–6	Optical
Lin et al., 2005 [54]	7.6·10−6	Optical
Cui, Kang et al., 2008 [55]	1.7·10−6	Electrochemical
Zhao et al., 2009 [56]	1.2·10−6	Electrochemical