title: An organic indicator functionalized graphene oxide nanocomposite-based colorimetric assay for the detection of sarcosine.
abstract: Rapid detection of sarcosine is a key requirement for both diagnosis and treatment of disease. We report here a simple yet sensitive colorimetric nanocomposite platform for rapid detection of sarcosine in alkaline media. The approach exploited the benefits of a rapid color-producing reaction between an organic indicator, 1,2-naphthoquinone-4-sulphonic acid sodium salt (NQS), and the analyte of sarcosine species as well as the good catalytic ability of graphene oxide (GO) to the formation of highly colored products due to its good water dispersibility, extremely large surface area and facile surface modification. As a result, a NQS functionalized GO nanocomposite through π-π stacking has been demonstrated to be useful as a highly efficient catalyst system for the selective and sensitive colorimetric determination of sarcosine by providing a nanocomposite-amplified colorimetric response. Meanwhile, the strategy offered excellent selectivity toward sarcosine species against other amino acids as well as a satisfying detection limit of 0.73 μM. More importantly, by using an electrochemical method, a credible sensing mechanism of GO nanocomposite-based colorimetric platform for a special analyte determination can be easily verified and elucidated, which also provides an attractive alternative to conventional characterization strategies.
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Zhonghua
authors.initials: Z
authors.lastname: Xue
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Bo
authors.initials: B
authors.lastname: Yin
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Mengqian
authors.initials: M
authors.lastname: Li
authors.affiliation: School of chemistry & environmental science, Lanzhou City University, Lanzhou, 730070, China.
authors.forename: Honghong
authors.initials: H
authors.lastname: Rao
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Xiuhui
authors.initials: X
authors.lastname: Liu
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Xinbin
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou, 730070, China. xzh@nwnu.edu.cn luxq@nwnu.edu.cn.
authors.forename: Xiaoquan
authors.initials: X
authors.lastname: Lu
mesh_terms: D002384:Catalysis; D003124:Colorimetry / Q000379:methods*; D003362:Cost-Benefit Analysis; D004563:Electrochemistry; D006108:Graphite / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry*; D036103:Nanotechnology; D009285:Naphthoquinones / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D012521:Sarcosine / Q000032:analysis*; D012995:Solubility; D013451:Sulfonic Acids / Q000737:chemistry
chemical_list: D009285:Naphthoquinones; D010087:Oxides; D013451:Sulfonic Acids; D006108:Graphite; C040756:1,2-naphthoquinone; D012521:Sarcosine