Peroxidase-like catalytic activity of copper ions and its application for highly sensitive detection of glypican-3.
Glypican-3 (GPC3) might be used as new biomarker of liver cancer for the development of new diagnostic methods. The most commonly used methods for protein detection are based on natural enzymes, which are easily affected by environmental conditions and suffer from the rigorous preparation conditions. Thus, the development of new enzyme mimetics with high and stable catalytic activity is of great significance in diagnostic applications. In this paper, copper ions (Cu2+) was found to possess the peroxidase-like catalytic activity, which can catalyze H2O2-mediated oxidation of peroxidase substrate and obtain the oxidation product with color change. This catalytic activity is much more stable than other nanomaterials based peroxidase mimetics, and can significantly increase by increasing the concentration of H2O2. It is worth mentioning that the absorbance signal induced by 5 nM Cu2+can be easily detected. This Cu2+-catalyzed reaction can be also applied in the detection of GPC3 by using the anti-GPC3 antibody functionalized CuO NPs, which can release the Cu2+by dissolved in HCl solution. This method permits detection of as low as 0.26 pg mL-1GPC3. This sensitivity is about one or several magnitudes higher than that of ELISA or other peroxidase mimetics based methods. The high catalytic activity of Cu2+and the signal amplification process of CuO NPs into high amount of Cu2+also make this method more simple and effective.
The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
Aixian
A
Zheng
The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
Xiaolong
X
Zhang
The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China.
Ju
J
Gao
The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China. Electronic address: xiaoloong.liu@gmail.com.
Xiaolong
X
Liu
The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, PR China; The Liver Center of Fujian Province, Fujian Medical University, Fuzhou 350025, PR China; Liver Disease Center, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, PR China. Electronic address: drjingfeng@126.com.
Jingfeng
J
Liu
D040761:Biomimetic Materials / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D053673:Glypicans / Q000032:analysis*; D056945:Hep G2 Cells; D006801:Humans; D057230:Limit of Detection; D053758:Nanoparticles / Q000737:chemistry; D009195:Peroxidase / Q000378:metabolism*
D053673:Glypicans; D003300:Copper; D009195:Peroxidase
Copper ions; Enzyme mimetics; Glypican-3; Peroxidase-like catalytic activity; Signal amplification