TY  - JOUR
AU  - Weiß, Lennart JK
AU  - Lubins, Georg
AU  - Music, Emir
AU  - Rinklin, Philipp
AU  - Banzet, Marko
AU  - Peng, Hu
AU  - Terkan, Korkut
AU  - Mayer, Dirk
AU  - Wolfrum, Bernhard
TI  - Single-Impact Electrochemistry in Paper-Based Microfluidics
JO  - ACS sensors
VL  - 7
IS  - 3
SN  - 2379-3694
CY  - Washington, DC
PB  - ACS Publications
M1  - FZJ-2023-01340
SP  - 884-892
PY  - 2022
AB  - Microfluidic paper-based analytical devices (μPADs) have experienced an unprecedented story of success. In particular, as of today, most people have likely come into contact with one of their two most famous examples─the pregnancy or the SARS-CoV-2 antigen test. However, their sensing performance is constrained by the optical readout of nanoparticle agglomeration, which typically allows only qualitative measurements. In contrast, single-impact electrochemistry offers the possibility to quantify species concentrations beyond the pM range by resolving collisions of individual species on a microelectrode. Within this work, we investigate the integration of stochastic sensing into a μPAD design by combining a wax-patterned microchannel with a microelectrode array to detect silver nanoparticles (AgNPs) by their oxidative dissolution. In doing so, we demonstrate the possibility to resolve individual nanoparticle collisions in a reference-on-chip configuration. To simulate a lateral flow architecture, we flush previously dried AgNPs along a microchannel toward the electrode array, where we are able to record nanoparticle impacts. Consequently, single-impact electrochemistry poses a promising candidate to extend the limits of lateral flow-based sensors beyond current applications toward a fast and reliable detection of very dilute species on site.
LB  - PUB:(DE-HGF)16
C6  - 35235291
UR  - <Go to ISI:>//WOS:000785008500023
DO  - DOI:10.1021/acssensors.1c02703
UR  - https://juser.fz-juelich.de/record/1005152
ER  -