Amperometric indicator displacement assay for biomarker monitoring: Indirectly sensing strategy for electrochemically inactive sarcosine.
Indicator displacement assay plays a fundamental role in the development of chemosensors. We explored here an ingenious yet effective strategy for amperometric assay of electrochemically inactive sarcosine based on an indicator displacement principle, in which 1,2-naphthoquinone-4-sulphonic acid sodium salt (NQS) was proposed as the receptor and the electroactive Ru(NH3)63+cations used as an indicator. Due to the stronger binding affinity of the NQS toward sarcosine than toward Ru(NH3)63+, the developed amperometric indicator displacement assay (A-IDA) exhibits high selectivity and excellent sensitivity toward sarcosine determination as well as with a lower detection limit (30.00nM, S/N =3).
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China. Electronic address: xzhlab@hotmail.com.
Zhonghua
Z
Xue
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
Hui
H
Wang
School of Chemistry & Environmental Engineering, Lanzhou City University, Lanzhou 730070, PR China.
Honghong
H
Rao
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
Nan
N
He
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
Xiaofen
X
Wang
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China.
Xiuhui
X
Liu
Key Laboratory of Bioelectrochemistry & Environmental Analysis of Gansu Province, College of Chemistry & Chemical Engineering, Northwest Normal University, Lanzhou 730070, PR China. Electronic address: luxq@nwnu.edu.cn.
Xiaoquan
X
Lu
D001681:Biological Assay; D015415:Biomarkers / Q000032:analysis*; D004563:Electrochemistry; D006801:Humans; D009285:Naphthoquinones / Q000737:chemistry*; D017975:Ruthenium Compounds / Q000737:chemistry*; D012521:Sarcosine / Q000032:analysis* / Q000737:chemistry; D013451:Sulfonic Acids / Q000737:chemistry*
D015415:Biomarkers; D009285:Naphthoquinones; D017975:Ruthenium Compounds; D013451:Sulfonic Acids; C505589:1,2-naphthoquinone-4-sulfonic acid; D012521:Sarcosine
Amperimetric sensor; Colorimetric sensor; Electrochemical inactive target; Indicator displacement assay; Sarcosine