0

Full Content is available to subscribers

Subscribe/Learn More  >

Investigation of Ion Transport in Polypyrrole Modified Ultra-Microelectrodes During Scanning Electrochemical Microscopy

[+] Author Affiliations
Vinithra Venugopal, Vijay Venkatesh, Vishnu Baba Sundaresan

Ohio State University, Columbus, OH

Paper No. SMASIS2016-9191, pp. V002T06A014; 7 pages
doi:10.1115/SMASIS2016-9191
From:
  • ASME 2016 Conference on Smart Materials, Adaptive Structures and Intelligent Systems
  • Volume 2: Modeling, Simulation and Control; Bio-Inspired Smart Materials and Systems; Energy Harvesting
  • Stowe, Vermont, USA, September 28–30, 2016
  • Conference Sponsors: Aerospace Division
  • ISBN: 978-0-7918-5049-7
  • Copyright © 2016 by ASME

abstract

Scanning electrochemical microscopy (SECM) is an electrochemical technique used to measure faradaic current changes local to the surface of a sample. The incorporation of shear force (SF) feedback in SECM enables the concurrent acquisition of topographical data of substrates along with electrochemical measurements. Contemporary SECM measurements require a redox mediator such as ferrocene methanol (FcMeOH) for electrochemical measurements; however, this could prove detrimental in the imaging of biological cells. In this article, nanoscale polypyrrole membranes doped with dodecylbenzene sulfonate (PPy(DBS)) are deposited at the tip of an ultra-microelectrode (UME) to demonstrate a novel modification of the contemporary SECM-SF imaging technique that operates in the absence of a redox mediator. The effect of distance from an insulating substrate and bulk electrolyte concentration on sensor response are examined to validate this technique as a tool for correlated topographical imaging and cation flux mapping. Varying the distance of the PPy(DBS) tipped probe from the substrate in a solution containing NaCl causes a localized change in cation concentration within the vicinity of the membrane due to hindered diffusion of ions from the bulk solution to the diffusion field. The cation transport into the membrane in close proximity to the substrate is low as compared to that in the electrolyte bulk and asymptotically approaches the bulk value at the sense length. At a constant height from the base, changing the bulk NaCl concentration from 5 mM to 10 mM increases the filling efficiency from 35% to 70%. Further, the sense length of this modified electrode in NaCl is about 440 nm which is significantly lower as compared to that of a bare electrode in ferrocene methanol (5–20 μm). It is postulated that this novel technique will be capable of producing high resolution maps of surface cation concentrations, thus having a significant impact in the field of biological imaging.

Copyright © 2016 by ASME
Topics: Microscopy

Figures

Tables

Interactive Graphics

Video

Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

NOTE:
Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In