TY - JOUR
T1 - Facile Monitoring of Water Hardness Levels Using Responsive Complex Emulsions
AU - Pavlovic, Marko
AU - Ramiya Ramesh Babu, Heman Kumar
AU - Djalali, Saveh
AU - Vraneš, Milan
AU - Radonić, Vasa
AU - Zeininger, Lukas
N1 - Funding Information:
This work was supported by the ANTARES project, which received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement no. 664387. S.D. and L.Z. gratefully acknowledge funding from the Max Planck Society and through the Emmy Noether Program of the German Research Foundation (grant no. ZE 1121/3-1).
Publisher Copyright:
© 2021 American Chemical Society
PY - 2021/7/13
Y1 - 2021/7/13
N2 - The cationic content of water represents a major quality control parameter that needs to be followed by a rapid, on-site, and low-cost method. Herein, we report a novel method for a facile monitoring of the mineral content of drinking water by making use of responsive complex emulsions. The morphology of biphasic oil-in-water droplets solely depends on the balance of interfacial tensions, and we demonstrate that changes in the surfactant effectiveness, caused by variations in the mineral content inside the continuous phase, can be visualized by monitoring internal droplet shapes. An addition of metal cations can significantly influence the surfactant critical micelle concentrations and the surface excess values and therefore induce changes in the effectiveness of ionic surfactants, such as sodium dodecyl sulfate. The morphological response of Janus emulsions droplets was tracked via a simple microscopic setup. We observed that the extent of the droplet response was dependent on the salt concentration and valency, with divalent cations (responsive for water hardness), resulting in a more pronounced response. In this way, Ca2+and Mg2+levels could be quantitatively measured, which we showcased by determination of the mineral content of commercial water samples. The herein demonstrated device concept may provide a new alternative rapid monitoring of water hardness levels in a simple and cost-effective setup.
AB - The cationic content of water represents a major quality control parameter that needs to be followed by a rapid, on-site, and low-cost method. Herein, we report a novel method for a facile monitoring of the mineral content of drinking water by making use of responsive complex emulsions. The morphology of biphasic oil-in-water droplets solely depends on the balance of interfacial tensions, and we demonstrate that changes in the surfactant effectiveness, caused by variations in the mineral content inside the continuous phase, can be visualized by monitoring internal droplet shapes. An addition of metal cations can significantly influence the surfactant critical micelle concentrations and the surface excess values and therefore induce changes in the effectiveness of ionic surfactants, such as sodium dodecyl sulfate. The morphological response of Janus emulsions droplets was tracked via a simple microscopic setup. We observed that the extent of the droplet response was dependent on the salt concentration and valency, with divalent cations (responsive for water hardness), resulting in a more pronounced response. In this way, Ca2+and Mg2+levels could be quantitatively measured, which we showcased by determination of the mineral content of commercial water samples. The herein demonstrated device concept may provide a new alternative rapid monitoring of water hardness levels in a simple and cost-effective setup.
UR - http://www.scopus.com/inward/record.url?scp=85110958471&partnerID=8YFLogxK
U2 - 10.1021/acs.analchem.1c00868
DO - 10.1021/acs.analchem.1c00868
M3 - Article
C2 - 34212731
AN - SCOPUS:85110958471
VL - 93
SP - 9390
EP - 9396
JO - Industrial And Engineering Chemistry Analytical Edition
JF - Industrial And Engineering Chemistry Analytical Edition
SN - 0019-7866
IS - 27
ER -