Non-aggregation based label free colorimetric sensor for the detection of Cr (VI) based on selective etching of gold nanorods

作者：Li Fei Ming; Liu Jia Ming^*; Wang Xin Xing; Lin Li Ping; Cai Wen Lian; Lin Xuan; Zeng Yi Na; Li Zhi Ming; Lin Shao Qin

来源：Sensors and Actuators B: Chemical , 2011, 155(2): 817-822.

DOI：10.1016/j.snb.2011.01.054

• Gold nanorod
• Etching
• Non-aggregation based label free colorimetric sensor
• Cr (VI)

Gold nanorods (GNRs) exhibit strong longitudinal surface plasmon resonance absorption (LPA), which is highly dependent on its aspect ratio (length/width). The strong oxidization of Cr (VI) enables it to etch GNRs selectively at tips. The redox etching causes the aspect ratio of GNRs to decrease, resulting in the LPA blue shifts and the color of GNRs distinctly changes. Besides, the blue shift is linear to the concentration of Cr (VI) in the range of 0.1-20 mu M. Thus, a non-aggregation based label free colorimetric sensor for the detection of Cr (VI) has been developed based on the selective etching of GNRs. The proposed calorimetric sensor is responsive, simple, sensitive (detection limit is 8.8 x 10(-8) M) and selective, and it has been successfully applied to the detection of Cr (VI) in drinking water and sea water. Moreover, the mechanism of colorimetric sensor for the detection of Cr (VI) was also discussed.

• 出版日期2011-7-20
• 单位福建教育学院; 闽南师范大学; 漳州职业技术学院