Please use this identifier to cite or link to this item:
Authors: Niu, Ran
Khodorov, Stanislav
Weber, Julian
Reinmüller, Alexander
Palberg, Thomas
Title: Large scale micro-photometry for high resolution pH-characterization during electro-osmotic pumping and modular micro-swimming
Online publication date: 15-Jul-2022
Language: english
Abstract: Micro-fluidic pumps as well as artificial micro-swimmers are conveniently realized exploiting phoretic solvent flows based on local gradients of temperature, electrolyte concentration or pH. We here present a facile micro-photometric method for monitoring pH gradients and demonstrate its performance and scope on different experimental situations including an electro-osmotic pump and modular micro-swimmers assembled from ion exchange resin beads and polystyrene colloids. In combination with the present microscope and DSLR camera our method offers a 2 μ m spatial resolution at video frame rate over a field of view of 3920 × 2602 μ m 2 . Under optimal conditions we achieve a pH-resolution of 0.05 with about equal contributions from statistical and systematical uncertainties. Our quantitative micro-photometric characterization of pH gradients which develop in time and reach out several mm is anticipated to provide valuable input for reliable modeling and simulations of a large variety of complex flow situations involving pH-gradients including artificial micro-swimmers, microfluidic pumping or even electro-convection.
DDC: 530 Physik
530 Physics
Institution: Johannes Gutenberg-Universität Mainz
Department: FB 08 Physik, Mathematik u. Informatik
Place: Mainz
Version: Published version
Publication type: Zeitschriftenaufsatz
License: CC BY
Information on rights of use:
Journal: New journal of physics
Pages or article number: Art. 115014
Publisher: IOP
Publisher place: London
Issue date: 2017
ISSN: 1367-2630
Publisher URL:
Publisher DOI: 10.1088/1367-2630/aa9545
Appears in collections:DFG-OA-Publizieren (2012 - 2017)

Files in This Item:
  File Description SizeFormat
large_scale_microphotometry_f-20220714110252934.pdf1.77 MBAdobe PDFView/Open