Tunable reverse electrodialysis microplatform with geometrically controlled self-assembled nanoparticle network

Abstract

Clean and sustainable energy generation from ambient environments is important not only for large scale systems, but also for tiny electrical devices, because of the limitations of batteries or external power sources. Chemical concentration gradients are promising energy resources to power micro/nanodevices sustainably without discharging any pollutants. In this paper, an efficient microplatform based on reverse electrodialysis, which enables high ionic flux through three dimensional nanochannel networks for high power energy generation, is demonstrated. Highly effective cation-selective nanochannel networks are realized between two microfluidic channels with geometrically controlled in situ self-assembled nanoparticles in a cost-effective and simple way. The nano-interstices between the assembled nanoparticles have a role as collective three-dimensional nanochannel networks and they allow higher ionic flux under concentration gradients without decreasing diffusion potential, compared to standard one-dimensional nanochannels. An in-depth experimental study with theoretical analysis shows that the electrical power of the presented system can be flexibly tuned or further optimized by changing the size, material, and shape of the assembled nanoparticles or by the geometric control of the microchannel. This microfluidic power generation system can be readily integrated with existing lab on a chip systems in the near future and can also be utilized to investigate nanoscale electrokinetics.

Enabling electrical biomolecular detection in high ionic concentrations and enhancement of the detection limit thereof by coupling a nanofluidic crystal with reconfigurable ion concentration polarization

“…The nafion resin propagated along the channel automatically due to capillary force, and self-stopped at the nanofilter-microchannel neck, because an additional pressure was needed for the nafion resin to pass the geometrical expansion. 51 The resin was cured by heating the chip at 95°C on the hotplate for 10 min. (2) Reservoir fabrication: A PDMS slab with four punched holes was bonded to the backside of the silicon substrate by plasma bonding, with the punched holes aligned to the contact holes of the chip.…”

“…1(d)). 51 Nanoparticles of 110/200/510 nm were assembled into the NFC in the central region due to the filtration effect of the nanofilter arrays (Fig. 1(e)).…”

“…It is worth mentioning that, although in this work we required electron beam lithography to fabricate the nanofilters that may add to the cost of the device, we believe that the device can be made disposable via injection molding, using low cost plastic materials in the future, in which assembly of nanoparticles will be controlled by the capillary force instead of nanofilters. 51 Finally, the device is ready for experiments after the assembled nanoparticles were dried and stabilized. The photos of the whole chip and testing system were shown in the Supplementary Information.…”

Bioinspired Energy Conversion in Nanofluidics: A Paradigm of Material Evolution

“…[47,48] At the present stage, the fabrication of state-of-the-art 1D nanofluidic devices relies on expensive scientific equipment and laborious material-processing steps. Toward practical applications, one immediate challenge is to integrate individual nanoscale ionic conductors into macroscopic membrane materials in a facile and cost-efficient way.…”

In vitro quantitative analysis of Salmonella typhimurium preference for amino acids secreted by human breast tumor

“…Finally, the PDMS devices and a slide glass were plasma treated (50 sccm of O 2 and 70 W) for 40 s in an O 2 plasma machine (Cute-MP, Femto Science, Korea) and were then bonded each other to form the microfluidic channels. Figure 2c shows the time sequence microscopic images for a formation of the microchannel networks using microspheres within the shallow channel, as reported previously [14,[22][23][24][25]. The PDMS device with shallow channel and deep channels (source/sink channel and center chamber) were fabricated as shown in Fig.…”