The long-range effect induced by untying hydrogen bonds for single cell test using SECM. (20th July 2016)

• Record Type: Journal Article
• Authors: Zheng, Qing; Yang, Yifan; Yan, Yuanyuan; Yu, Yu; Liu, Yao; Gao, Wenyu; Ding, Kejian; Shao, Huibo
• Is Part Of: Electrochimica acta. Volume 207(2016)
• Page Start: 135
• Page End: 142
• Publication Date: 2016-07-20
• Subjects: Scanning electrochemical microscopy -- Hydrogen bonds -- Self-assembled monolayer -- Long-range effect; Electrochemistry -- Periodicals; Electrochemistry, Industrial -- Periodicals; 541.37
• DOI: 10.1016/j.electacta.2016.04.174
• Languages: English
• ISSNs: 0013-4686

Abstract

Graphical abstract: Highlights: The enhanced positive feedback current of SECM is observed at a large tip-substrate separation in the case of a 3-MPA SAM. The long-range effect is resulting from concentration increment of redox species by untying the hydrogen bonds beforehand formed between the tip redox species and the 3-MPA SAM. The long-range effect is applied to the single cell test using SECM which is beneficial for cell tests without affecting the natural metabolic pathway and cell morphology. Abstract: The enhanced positive feedback current of scanning electrochemical microscopy (SECM) is observed at a large separation between the tip and the substrate surface in the case of a 3-mercaptopropionic acid (3-MPA) self-assembled monolayer (SAM). The effect that induces the large separation (named the long-range effect) is confirmed by SECM and quantitatively studied by electrochemical quartz crystal microbalance (EQCM). A key finding is that the long-range effect results from untying hydrogen bonds beforehand formed between the hydroxyl group of tip redox species and the carboxyl group of 3-MPA SAM. It is found that the long-range effect is increased with the packing density of the 3-MPA SAM. On the basis of these findings, the long-range effect is applied to the nondestructive test of living cells using SECM.