title: Colorimetric Strategy for Highly Sensitive and Selective Simultaneous Detection of Histidine and Cysteine Based on G-Quadruplex-Cu(II) Metalloenzyme.
abstract: In this present work, we proposed a colorimetric strategy for simultaneous detection of histidine and cysteine based on G-quadruplex-Cu(II) metalloenzyme for the first time. Because of the adding of histidine or cysteine, the formation of G-quadruplex-Cu(II) metalloenzyme will be disturbed, thus the catalytic activity to TMB-H2O2 reaction is inversely proportional to the concentration of histidine or cysteine. With this strategy, the limit of detection in experimental measurement for histidine and cysteine is 10 nM and 5 nM, respectively, which are both lower than previous colorimetric arrays. With the help of NEM, cysteine is alkylated and the reaction between Cu(2+) is inhibited, so the selectivity can also be guaranteed. The cost is quite low since the developed array is label free and enzyme free by using low-cost DNA and Cu(2+). More importantly, the colorimetric detection operation is very simple without any further modification process.
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun, Jilin 130022, China.|Department of Chemistry and Environmental Engineering, Changchun University of Science and Technology , Changchun, Jilin 130022, China.
authors.forename: Changtong
authors.initials: C
authors.lastname: Wu
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun, Jilin 130022, China.
authors.forename: Daoqing
authors.initials: D
authors.lastname: Fan
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun, Jilin 130022, China.
authors.forename: Chunyang
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology, Ministry of Education , Tianjin 300457, China.
authors.forename: Yaqing
authors.initials: Y
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun, Jilin 130022, China.
authors.forename: Erkang
authors.initials: E
authors.lastname: Wang
mesh_terms: D003124:Colorimetry / Q000379:methods*; D003545:Cysteine / Q000032:analysis*; D004798:Enzymes / Q000737:chemistry*; D054856:G-Quadruplexes; D006639:Histidine / Q000032:analysis*; D057230:Limit of Detection; D008667:Metalloproteins / Q000737:chemistry*
chemical_list: D004798:Enzymes; D008667:Metalloproteins; D006639:Histidine; D003545:Cysteine