Trotter, MartinJuric, DanielBagherian, ZahraBorst, NadineGläser, KerstinMeissner, ThomasStetten, Felix vonZimmermann, André2024-09-202024-09-2020201424-82201903864690http://nbn-resolving.de/urn:nbn:de:bsz:93-opus-ds-149797http://elib.uni-stuttgart.de/handle/11682/14979http://dx.doi.org/10.18419/opus-14960Inkjet technology as a maskless, direct-writing technology offers the potential for structured deposition of functional materials for the realization of electrodes for, e.g., sensing applications. In this work, electrodes were realized by inkjet-printing of commercial nanoparticle gold ink on planar substrates and, for the first time, onto the 2.5D surfaces of a 0.5 mm-deep microfluidic chamber produced in cyclic olefin copolymer (COC). The challenges of a poor wetting behavior and a low process temperature of the COC used were solved by a pretreatment with oxygen plasma and the combination of thermal (130 °C for 1 h) and photonic (955 mJ/cm²) steps for sintering. By performing the photonic curing, the resistance could be reduced by about 50% to 22.7 µΩ cm. The printed gold structures were mechanically stable (optimal cross-cut value) and porous (roughness factors between 8.6 and 24.4 for 3 and 9 inkjet-printed layers, respectively). Thiolated DNA probes were immobilized throughout the porous structure without the necessity of a surface activation step. Hybridization of labeled DNA probes resulted in specific signals comparable to signals on commercial screen-printed electrodes and could be reproduced after regeneration. The process described may facilitate the integration of electrodes in 2.5D lab-on-a-chip systems.eninfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by/4.0/660article2020-03-05